DAVE: everything he said

785 posts and passages, oldest first, as one-line summaries in our words. Each link opens the original.

• 2015-03-02Watts says the 164,000-tap filter runs on an LX75 FPGA after four redesigns for timing closure, using 160 DSP cores at half speed for the first WTA stage. Head-Fi, Mar 2015
• 2015-03-02Watts defers discussing the 164,000-tap filter's sound until launch, saying its LX75 FPGA draws 5W and could only go portable with 10nm FPGAs in five or more years. Head-Fi, Mar 2015
• 2015-03-03Watts says Project xxxx is a digital pre-amp with headphone drive, which he can discuss closer to its May launch. Head-Fi, Mar 2015
• 2015-03-13Watts says Project xxxx's headphone drive has slightly more voltage and the same current as Hugo, and it cannot be battery powered since its FPGA dissipates 5W. Head-Fi, Mar 2015
• 2015-03-14Watts defends Hugo's color volume display, gives its range from +18 dB (white) to -70 dB (dark brown), prefers digital volume to pots, and says Project xxxx keeps the colors. Head-Fi, Mar 2015
• 2015-04-20Watts says Project xxxx launches at Munich and is unlikely to become a Hugo upgrade, since its improvements need far more FPGA capacity than Hugo has. Head-Fi, Apr 2015
• 2015-05-16Watts says it is impossible because DAVE's large FPGA dissipates 5W against Hugo's 0.8W, needs a machined heatsink, and uses 166 DSP cores for WTA filtering. needs context Head-Fi, May 2015
• 2015-05-18Watts says DAVE's output stage is a second-order analog noise shaper with negligible distortion change into 33 ohms and no rising HF distortion, keeping one global feedback path. Head-Fi, May 2015
• 2015-05-20Watts says DAVE stands for Digital to Analogue Veritas in Extremis, explains the name, and says its development built on understanding why Hugo sounded so musical. HIFICLUBE.NET JVH 4
• 2015-05-20Watts says DAVE's FPGA is 10 times more complex than Hugo's, giving 164,000 taps, an enhanced WTA algorithm, FIR filtering to 256 times, then further filtering to 2048. HIFICLUBE.NET JVH 45
• 2015-05-20Watts calls a 256-times FIR filter a world record, cites 166 parallel DSP cores, and says sampling theory needs an infinite-tap, infinitely oversampling filter for perfect reconstruction. HIFICLUBE.NET JVH 1:17
• 2015-05-20Watts says digital engineers underestimated the importance of reconstructing the original continuous signal with timing accuracy, and that improving time resolution proved a big benefit. HIFICLUBE.NET JVH 2:12
• 2015-05-20Watts says the noise shaper converts the 24-bit 104 MHz filtered signal to 5 bits feeding the discrete pulse array, so its performance matters greatly. HIFICLUBE.NET JVH 2:41
• 2015-05-20Watts says it will run with DSD512. HIFICLUBE.NET JVH 3:15
• 2015-05-20Watts says DSD is converted to PCM without decimation using improved filters, answering earlier criticism of his decimating approach, which he says had sounded better than previous filters. HIFICLUBE.NET JVH 3:20
• 2015-05-20Watts says decimation is fine if followed by a WTA filter, but 140 dB decimation accuracy proved insufficient: non-decimating versions sound noticeably better and measurements show distortion at -140 dB. HIFICLUBE.NET JVH 3:52
• 2015-05-20Watts says that tuning Hugo, better noise shaper performance improved perceived depth, limited by Hugo's gates; for DAVE he began listening tests from Hugo's roughly 200 dB. HIFICLUBE.NET JVH 5:32
• 2015-05-20Watts says raising noise shaper performance to 220, 240 and 260 dB each improved depth with no apparent limit, so he redesigned the noise shapers, reaching 350 dB. HIFICLUBE.NET JVH 6:30
• 2015-05-20Watts says the 350 dB is actual digital-domain performance: a 48-bit perfect sine feeds the noise shaper, and an FFT of the summed pulse array elements shows 350 dB in-band. HIFICLUBE.NET JVH 7:13
• 2015-05-20Watts says the depth is accurate, not added reverb: dry recordings stay at the speakers. He is unsure whether 350 dB is truly needed or an analog mechanism explains it. HIFICLUBE.NET JVH 9:00
• 2015-06-06Watts says he will talk more about DAVE as full production approaches, because there is much more to it than 164k taps. Head-Fi, Jun 2015
• 2015-06-06Watts says the unit is not class D: like Hugo, a single-stage amplifier drives line and headphone outputs, giving 6v RMS with the same 0.5A RMS current as Hugo. needs context Head-Fi, Jun 2015
• 2015-06-18Watts explains the pulse array's analog-like distortion, why half-band filters keep original samples, and how a 256-tap WTA beat a 2048-tap half-band Kaiser filter in the late 90s. Head-Fi, Jun 2015
• 2015-06-18Watts says half-band filters time transients poorly (-6dB at FS/2); 16-bit sinc accuracy needs about 1M taps; Hugo is about 12 bits, Dave about 14. Head-Fi, Jun 2015
• 2015-06-18Watts says DAVE has an asymmetric WTA filter setting with lower delay for video use, and that DAVE production is scheduled for October 2015. Head-Fi, Jun 2015
• 2015-06-27Watts defines noise floor modulation, says it is audible at immeasurable levels, and shows APx555 plots of Dave with an unchanged noise floor near -180dB with and without signal. Head-Fi, Jun 2015
• 2015-06-30Watts says Dave's wide output level and low noise make power amp gain unimportant, and Dave is single-ended because that is best for sound, though harder than differential. Head-Fi, Jun 2015
• 2015-07-14Watts says balanced doubles signal-path components and costs transparency; silicon DACs need differential operation, but his discrete DACs are single-ended, which forced solving problems differential hides. Head-Fi, Jul 2015
• 2015-07-31Watts says the noise shaper is 5 bits at 104 MHz, 17th order, gives 350dB THD and noise in the digital domain, and resolves audio to 48-bit accuracy. Head-Fi, Jul 2015
• 2015-07-31Watts gives crosstalk of 120dB, distortion below -150dB and 21-bit noise, says such numbers do not show sound quality, and compares headphone drive with TT. Head-Fi, Jul 2015
• 2015-08-01Watts says Dave, like Hugo, uses the same output for headphones and line level; XLR gives up to 12v RMS but is not for headphones; RCA gives 6v RMS. Head-Fi, Aug 2015
• 2015-08-01Watts says, at 1% THD with full batteries, the unit actually gives 5.4v RMS into 300 ohms, and Dave will be rated above 6v at 1%. needs context Head-Fi, Aug 2015
• 2015-09-14Watts says Hugo is FPGA limited, so lessons from Dave cannot be applied; Dave may be upgradable via Chord or the distributor, only for a clear subjective improvement. Head-Fi, Sep 2015
• 2015-09-25Watts says John Franks is showing a Dave close to production standard for PCM, but without the new non-decimating DSD filters he only just got running. Head-Fi, Sep 2015
• 2015-09-25Watts argues DSD is flawed by its format: limited noise-shaper resolution loses small signals and depth, and level-dependent timing non-linearity softens transients and compresses timbre. Head-Fi, Sep 2015
• 2015-10-01Watts says metal contacts and noise shapers cause the same small-signal distortion that truncates depth, the brain detects levels no instrument measures, and HF distortion alters transient timing. Head-Fi, Oct 2015
• 2015-10-03Watts says pulse array's constant switching makes it immune to jitter, and USB purifiers are pointless for galvanically isolated Dave, Hugo TT and 2Qute; Hugo's issue is RF noise. Head-Fi, Oct 2015
• 2015-10-03Watts says Dave's UK retail price remains £7,995, production is on schedule for release later this month, and local pricing is set by distributors. Head-Fi, Oct 2015
• 2015-10-03Watts rebuts a Nagra DAC's marketing claims point by point: quantization noise, brickwall filter phase, oversampling as cheating, clocking, and DSD out-of-band noise. Head-Fi, Oct 2015
• 2015-10-06Watts says Dave uses one FPGA with ten times Hugo's capacity, drawing 5A, is still a work in progress, and has PCM+ and DSD+ programs, DSD+ offering lower latency. Head-Fi, Oct 2015
• 2015-10-06Watts says the filter is efficient enough to fit with the 164,000 taps and sounds very good, but not as good as Dave's non-decimating DSD+ filter. needs context Head-Fi, Oct 2015
• 2015-10-06Watts says Hugo and 2Qute will get no upgrades; Dave could be upgraded via distributor or Chord only for a substantial gain, which is less likely as his technology matures. Head-Fi, Oct 2015
• 2015-10-06Watts says the DSD+ filter could not be routed alongside the 164,000-tap PCM+ filter despite under 70% capacity, but the 82,000-tap low-latency filter is smaller. Head-Fi, Oct 2015
• 2015-10-30Watts says Dave is in a different league to the QBD76, comparing it to an iPhone 6 against a phone from ten years ago. Head-Fi, Oct 2015
• 2015-10-30Watts says Dave's depth, about four times Hugo's, comes from small-signal accuracy of its -350 dB noise shapers; timing gains offset the darkness that reducing noise floor modulation brought. Head-Fi, Oct 2015
• 2015-11-01Watts says Dave's 705/768 kHz DX outputs feed his non-switching digital power amps; the first, due next year, is 20W RMS with a 70W mono-block option. Head-Fi, Nov 2015
• 2015-11-02Watts says Dave's shipping delay is his, as production code is not finished; four prototype batches mean hardware changes are not expected. Head-Fi, Nov 2015
• 2015-11-10Watts says Dave's key gain is timing: WTA filtering to 256FS reconstructs timing to 88 nS, improving starting and stopping of notes, while depth comes from the noise shapers. Head-Fi, Nov 2015
• 2015-11-13Watts says Dave gives 6.75 V RMS at 1% THD, suggests demoing it with Abyss headphones he has not tried, and says production code is close. Head-Fi, Nov 2015
• 2015-11-21Watts says 6.75 V is into 300 ohms with a 0.5A RMS current limit, final code is being tweaked, and he will tour Asia with a production Dave. Head-Fi, Nov 2015
• 2015-11-21Watts explains Dave's DSD filtering, how out-of-band noise causes noise floor modulation heard as brightness, the 60 kHz HF filter helping even CD, and PCM+ versus DSD+ modes. Head-Fi, Nov 2015
• 2015-11-22Watts recounts developing Dave: smoothness from reduced noise floor modulation, Hugo-derived timing gains from 256FS WTA (88nS), and noise shapers raised from 200 to 350 dB for depth. Head-Fi, Nov 2015
• 2015-11-22Watts says not to upsample on a computer before his DACs; Dave's 166 DSP cores outpace a PC, and only the WTA algorithm targets transient timing errors. Head-Fi, Nov 2015
• 2015-11-23Watts says USB is Dave's best input by a tiny margin, then optical, and gives measurements: 6.8v RMS at 1% THD into 300 and 33 ohms, 55 milliohm output impedance. Head-Fi, Nov 2015
• 2015-11-23Watts says it reaches 121dB SPL with 6.8v driving it. needs context Head-Fi, Nov 2015
• 2015-11-23Watts lists his tour with a production Dave: Singapore, Manila, San Francisco, Indonesia, Kuala Lumpur and Singapore events from late November to mid-December. Head-Fi, Nov 2015
• 2015-11-24Watts says his new 64-core DSD filters could not be routed with the 164,000-tap WTA filter, hence two programs: PCM+ with Hugo DSD, and DSD+ with 82,000 taps. Head-Fi, Nov 2015
• 2015-12-01Watts ties depth to small-signal linearity, distinguishes it from noise floor modulation, and describes raising Dave's noise shapers from 200 to 350 dB with depth improving throughout. Head-Fi, Dec 2015
• 2015-12-01Watts says do not drive headphones from Dave's balanced outputs; Dave drives the HE1000 easily at 1.4W into 33 ohms, and an external amp would add distortion. Head-Fi, Dec 2015
• 2015-12-02Watts says Dave runs warm with large thermal margins, XLR headphone drive would distort, AES is poor for high rates, and Blu dual BNC works with proper RF cables. Head-Fi, Dec 2015
• 2015-12-04Watts says using Dave's headphone socket shuts down RCA and XLR via relays, restores the last headphone volume and enables crossfeed. Head-Fi, Dec 2015
• 2015-12-04Watts cites 27 years designing DACs and silicon chip experience, says no rival DAC has caught his attention, and that Dave sets new measurement standards. Head-Fi, Dec 2015
• 2015-12-04Watts gives the Malaysian distributor's details, clarifies that Dave's crossfeed control defaults to 0 (off), agrees crossfeed makes no sense for binaural recordings, and lists show dates. Head-Fi, Dec 2015
• 2015-12-11Watts defines musicality as emotional involvement, achieved by reducing errors the brain cannot decode: timing (long taps), small-signal accuracy for depth (2048FS noise shapers), and noise floor modulation. Head-Fi, Dec 2015
• 2015-12-13Watts says solder, metal contacts and passive parts affect sound, and that Chord boards are reflow soldered with silver paste in nitrogen, which sounds better than flow or hand soldering. Head-Fi, Dec 2015
• 2015-12-13Watts bets a new Dave against a bottle of Bollinger, and a Mojo against a beer, that they will beat the DACs a poster named for transparency and musicality. needs context Head-Fi, Dec 2015
• 2015-12-17Watts says he spent a month trying to make it seamless, but click-free, DC-protection-safe operation with an inaudible DC servo required this way; DSD runs as DoP or native ASIO, native only for DSD512. needs context Head-Fi, Dec 2015
• 2015-12-18Watts says Dave's HF filter is a 60 kHz cutoff set of 16FS-to-256FS WTA coefficients meant to cut ADC noise in hi-res recordings, and it unexpectedly improves 44.1 kHz too. Head-Fi, Dec 2015
• 2015-12-20Watts says the unit needs earthing for safety though its PSU is medical grade; he has used it unearthed on travels without sound penalty but agrees that may be hazardous. Head-Fi, Dec 2015
• 2015-12-30Watts says Dave is better than Mojo/Hugo, but Hugo was the first digital device that let him enjoy music rather than sound, despite being technically close to Qute. Head-Fi, Dec 2015
• 2015-12-30Watts says Dave sets a new benchmark in soundstage and measurements, criticizes reviewers who dismiss measured distortion as inaudible, and says removing any measurable distortion improves sound. Head-Fi, Dec 2015
• 2015-12-30Watts says Dave's output stage is a second-order analog noise shaper, so distortion barely changes with current; he suspects it helped HF linearity; output is 6.8 V into 33 and 300 ohms. Head-Fi, Dec 2015
• 2016-01-02Watts presents an APx555 J-test of Dave's USB input at 48 kHz: no data-related jitter, a -170 dB floor implying under 0.1 pS, and 0.2 pS mains jitter probably from the analyzer. Head-Fi, Jan 2016
• 2016-01-03Watts says Dave is insensitive to the digital source if the data is bit perfect, though the rest of a system may still be affected by RF noise and jitter. Head-Fi, Jan 2016
• 2016-01-04Watts explains that source differences heard with Hugo came from RF noise (noise floor modulation heard as brightness) and correlated ground currents degrading depth, which Dave's galvanic isolation removes. Head-Fi, Jan 2016
• 2016-01-09Watts says Mojo draws on ideas he began 30 years ago and that his background spans silicon chip design and high-end audio such as DAVE and Mojo. What Hi-Fi? 2:43
• 2016-01-09Watts says the A to D converter will match DAVE as the first commercial product, followed by pro audio versions, using DAVE's technology for better musicality in recordings. What Hi-Fi? 6:39
• 2016-01-11Watts says Dave has 20 elements, not 16, for overload margin: -3 dB gives 3 V RMS, +3 dB 6 V RMS, and clipping starts at +4 dB. Head-Fi, Jan 2016
• 2016-01-11Watts says TT beats Hugo via supercaps lowering PSU impedance, heavier metalwork, USB galvanic isolation and a better flip-flop reference supply that cuts distortion and noise some 4 dB. Head-Fi, Jan 2016
• 2016-01-18Watts explains that out-of-band RF noise intermodulates into noise floor modulation that sounds bright, so his DACs are limited to 50 or 60 kHz; Dave's HF filter targets DXD noise. Head-Fi, Jan 2016
• 2016-01-18Watts says the target is no out-of-band noise; Hugo is 50 kHz -3 dB, with no measurable noise from 23 to 50 kHz on CD; 1 MHz noise matters more. Head-Fi, Jan 2016
• 2016-01-18Watts says Dave's filter targeted ADC noise shaper noise in 176.4 kHz and above recordings, yet audibly warms redbook; he suspects lower noise floor modulation and keeps it on. Head-Fi, Jan 2016
• 2016-01-21Watts says Dave's FPGA has 132 DSP slices plus 34 fabric cores, his DACs reject source jitter equally, and source differences come from RF and correlated noise, removed by isolation. Head-Fi, Jan 2016
• 2016-01-27Watts heard no difference on 2Qute between its stock switching PSU and a car battery, unlike Qute, expects none with Dave, and says internal DAC RF noise dwarfs PSU noise. Head-Fi, Jan 2016
• 2016-01-29Watts says Hugo's noise shaping was limited by its four-element pulse array and FPGA; for DAVE each 20 dB improvement from 200 dB deepened the stage, reaching -350 dB. article, Jan 2016
• 2016-01-29Watts describes DAVE's 17th-order noise shaper with 46 integrators, his doubt whether 350 dB was the real cause, and a redesign confirming 350 dB or 48-bit accuracy is needed. article, Jan 2016
• 2016-01-29Watts says a single-stage 16FS WTA first stage sounded much better, by more than 26,000 versus 164,000 taps, and 256FS second-stage filtering improved timing accuracy from microseconds to nanoseconds. article, Jan 2016
• 2016-01-29Watts says Hugo development has stopped because its FPGA is too small, and that after he improved DAVE's WTA filters it sounds faster, tighter, more dynamic, neutral and transparent. article, Jan 2016
• 2016-01-29Watts explains that Hugo's sound hardened into low-impedance headphones, and that treating the output stage as a second-order analog noise shaper with nested feedback removed the distortion change at 32 ohms. article, Jan 2016
• 2016-01-29Watts gives DAVE's noise as -127 dB A-weighted at 2.5 V and distortion 0.000015 percent, and says his converters' distortion falls with signal level, unlike ladder, DSD or chip DACs. article, Jan 2016
• 2016-01-29Watts shows an APx555 plot with a -180 dB noise floor identical with no signal and at 2.5 V, and says noise floor modulation makes sound brighter and harder. article, Jan 2016
• 2016-02-14Watts says Dave's price came from the bill of materials and Chord's multipliers, recounts a dealer calling Dave too cheap against $50k DACs, and calls hi-res results mixed. Head-Fi, Feb 2016
• 2016-02-14Watts says dynamic range only shows residual hiss; Dave has a -180 dB noise floor with no measurable noise floor modulation or small-signal distortion, which matter more. Head-Fi, Feb 2016
• 2016-02-16Watts says Hugo's perception of timing, the starting and stopping of notes, surprised him, and Dave was about identifying and maximizing that factor, which he now understands technically. Head-Fi, Feb 2016
• 2016-02-18Watts says the crossfeed settings are 0 for none, 1 minimum and 3 maximum, the same as Hugo. Head-Fi, Feb 2016
• 2016-02-19Watts says production Dave has short-circuit protection resistors on the balanced XLR, so it will not drive headphones, and he prefers crossfeed setting 3 as closer to loudspeakers. Head-Fi, Feb 2016
• 2016-02-23Watts says optical will sound best and not to worry about source jitter because Dave eliminates it. Head-Fi, Feb 2016
• 2016-02-24Watts says for both TT and Dave USB is best, closely followed by optical, with coax last. Head-Fi, Feb 2016
• 2016-02-25Watts says he is designing an ADC to match Dave, and shows a Verilog simulation of Dave's noise shaper reproducing a -301 dB sine over a -380 dB floor. Head-Fi, Feb 2016
• 2016-02-25Watts says display blanking is normal: the display reads from flash, which cannot be read and written at once, so it blanks while settings are saved. Head-Fi, Feb 2016
• 2016-02-25Watts says the right button must be held at least a second to change the PCM+/DSD+ mode, and the unit should sound fabulous straight out of the box. Head-Fi, Feb 2016
• 2016-02-26Watts says a new upsampler PCB will bring Blu and Red Reference to Dave standard; until then Dave beats their old upsampler, so play 44.1. Dave cannot be upgraded. Head-Fi, Feb 2016
• 2016-02-28Watts says his power amp prototype has waited a year for testing, the amp and Davina are this year's priorities, and Dave driving it digitally should eliminate power amp sound. Head-Fi, Feb 2016
• 2016-03-01Watts says Dave was tested with HE1000 and all popular headphones and only one needed more power, no design suits every headphone, and he will stop answering a hostile poster. Head-Fi, Mar 2016
• 2016-03-01Watts says Dave is source-insensitive through bit-perfect data and immunity to jitter and noise, that depth needs perfect small-signal accuracy (350 dB noise shapers), so no pre-amp sounds better. Head-Fi, Mar 2016
• 2016-03-02Watts says the Abyss is 46 ohms, so Dave clips only past +5 dB, about 150 mA at 6.8 V, far below its 0.5 A current limit. Head-Fi, Mar 2016
• 2016-03-02Watts says 44.1/16 could in principle be near perfect, going from -330 to -350 dB noise shaping changed little, and 1M taps gives 16-bit sinc accuracy but needs costly FPGAs. Head-Fi, Mar 2016
• 2016-03-02Watts explains a DSP core is a dedicated FPGA multiply-accumulate module used to build WTA filters; Dave's FPGA has 132, so he built the missing 34 of 166 from fabric. Head-Fi, Mar 2016
• 2016-03-03Watts says his line count includes hand-copied coefficient data, verification and FPGA timing closure are the hardest parts, and Dave's roughly 100,000 lines took 9 months. Head-Fi, Mar 2016
• 2016-03-04Watts reports a successful Tokyo event where Japanese reviewers were astonished by Dave, with six reviewers placing personal orders. Head-Fi, Mar 2016
• 2016-03-04Watts says the intended price is nearer TT than Dave, and wishes Hugo were closer to Dave in sound so he need not carry Dave, now at 150,000 miles. needs context Head-Fi, Mar 2016
• 2016-03-04Watts explains the pulse array modulator and seven benefits (constant switching, jitter immunity, signal-unrelated currents, 104 MHz noise shaping), why Dave has 20 elements, and Mojo versus Dave THD. Head-Fi, Mar 2016
• 2016-03-05Watts says the Blu upsampler upgrade adds a second powerful FPGA for WTA processing, but only listening tests will show the benefit, and it ships only if worthwhile. Head-Fi, Mar 2016
• 2016-03-05Watts explains the 6-bit noise shaper output spans 0 to 20 elements with clamping, and the 4 elements beyond 16 keep every element switching and give headroom. Head-Fi, Mar 2016
• 2016-03-06Watts says Davina will test whether ADC bandlimiting changes sound once reconstruction is perfect, and whether dither can carry Dave's -301 dB, 64-bit-like small-signal accuracy at 44.1 kHz. Head-Fi, Mar 2016
• 2016-03-07Watts is quoted: developing Hugo in 2013 he thought 1 microsecond accuracy was enough, but developing DAVE he confirmed nanosecond-level accuracy has an effect. article, Mar 2016
• 2016-03-07Watts says ordinary DAC ICs use 100 taps at 8x or 16x; the article gives DAVE 164,000 taps at 256fs on 166 DSPs, and DAC64 1,000, QBD76 18,000, Hugo 26,000 taps. article, Mar 2016
• 2016-03-07Author says DAVE's enhanced noise shaper reproduces fine signals for spatial recognition; Watts contrasts hearing an organ's distance in church with recordings, saying recovering depth was his concern. article, Mar 2016
• 2016-03-07Watts once thought a 200dB noise shaper, 1,000 times better than high-end DACs, sufficient; developing DAVE he spent 90 days reaching 350dB and found depth improved markedly. article, Mar 2016
• 2016-03-13Watts explains AES17 dynamic range, gives Dave's 2.6 uV residual (-128.4 dB re 6.8 V, -117.7 dB re 2 V), and says its unchanging noise shows no noise floor modulation. Head-Fi, Mar 2016
• 2016-03-13Watts says Hi-Fi News made no mistake quoting noise re 2 V, though methods confuse readers, which is why he gives uV, and notes it confirmed Dave's 0.000007% distortion. Head-Fi, Mar 2016
• 2016-03-17Watts says Dave's 12 V balanced output comes at +3 dB volume for headphone headroom, and its digital path exceeds 350 dB accuracy, so volume does not change sound. Head-Fi, Mar 2016
• 2016-03-17Watts says the balanced output is not for driving headphones because its current is too low and impedance too high. Head-Fi, Mar 2016
• 2016-03-19Watts says Dave has no control electronics beyond the FPGA, cutting RF noise but forcing him to code everything including the display; he ran out of time for remote numbers. Head-Fi, Mar 2016
• 2016-03-22Watts agrees USB is a tad more detailed than optical, with optical showing barely measurable jitter degradation, because USB timing comes from the FPGA; both are galvanically isolated. Head-Fi, Mar 2016
• 2016-03-26Watts says the best pre-amp is none, and pre-amp bandwidth limiting is unnecessary with Dave because it has no significant out-of-band output. Head-Fi, Mar 2016
• 2016-03-29Watts says AB tests struggle to tell transparency from noise floor modulation, that better noise shapers in DAVE improved depth, and that Verilog simulation can quantify very small errors. Head-Fi, Mar 2016
• 2016-03-30Watts doubts Dave has much physical break-in, describing improvement over 8 weeks after new code as possibly brain break-in, and says Dave makes headphone differences more pronounced. needs context Head-Fi, Mar 2016
• 2016-03-31Watts says DAVE's volume is fully digital because analog controls have small-signal errors that degrade depth, and describes his 350 dB noise shaper and -301 dB test targets. Head-Fi, Mar 2016
• 2016-03-31Watts says DAVE's maximum attenuation is -75 dB with truncation noise near -350 dB, and explains how noise shapers attenuate signals near their resolution, harming depth. Head-Fi, Mar 2016
• 2016-04-02Watts contrasts fixed analog noise with signal-dependent small-signal distortion in R2R, delta-sigma and DSD DACs, and says DAVE's -127 dB dynamic range is set by hiss alone. Head-Fi, Apr 2016
• 2016-04-03Watts explains Class D's timing and noise floor modulation problems, then linear-amp issues: input-stage NFM, metal-contact non-linearity, feedback, and phase intermodulation, solvable by analog noise shaping. Head-Fi, Apr 2016
• 2016-04-10Watts says I2S is not supported as an input on DAVE. Head-Fi, Apr 2016
• 2016-04-10Watts says a built-in impulse detector switches the WTA filter out when it sees an impulse, which music cannot trigger, and that the windowed coefficients are fixed in the FPGA. Head-Fi, Apr 2016
• 2016-04-12Watts gives DAVE's first-stage WTA response as +0.000003 dB at 23 kHz, cites 166 DSP cores at 0.1 TIPS, and calls ringing a red herring for judging timing. Head-Fi, Apr 2016
• 2016-04-22Watts preferred a $2 USB cable over a $200 one on DAVE until he separated the headphone cable, then heard no difference; he says AES input injects RF, sounding brighter. Head-Fi, Apr 2016
• 2016-04-25Watts says optical handles 24/192 only with a good transmitter and cable, needing glass fiber for longer runs, and that his FPGA compensates the receiver's rise and fall time mismatch. Head-Fi, Apr 2016
• 2016-04-26Watts says DAVE adds no artificial depth, since flat recordings stay flat, and attributes compressed depth in DACs to small-signal amplitude errors rather than ringing. Head-Fi, Apr 2016
• 2016-04-28Watts calculates that an R2R DAC matching DAVE's -350 dB accuracy would need 0.000000000000003% resistors and 40 fS timing, and argues this cannot be achieved. Head-Fi, Apr 2016
• 2016-05-13Watts gives four reasons jitter is a non-issue on DAVE, including the pulse array's jitter insensitivity, and says reducing RF noise sounds warmer and softer and is more transparent. Head-Fi, May 2016
• 2016-05-13Watts doubts DAVE is sensitive to source RF via the mains and explains how RF intermodulating in analog electronics causes noise floor modulation that sounds harder and brighter. Head-Fi, May 2016
• 2016-05-13Watts says high-speed internal switchers sounded smoother and warmer than linear regulators in Hugo, forced more RF filtering, and cut DAVE's FPGA supply current from 5 A to 1 A. Head-Fi, May 2016
• 2016-05-14Watts reports DAVE via headphones sounded smoother and more natural with his laptop on battery than on mains, a small change he says is consistent with lower RF noise. Head-Fi, May 2016
• 2016-05-14Watts clarifies that DAVE's below-0.5 milliohm supply is a discrete linear reference circuit, not the switcher, with 0.22 uV noise to avoid measurable noise floor modulation. Head-Fi, May 2016
• 2016-05-17Watts explains DSD's and PWM's switching, jitter and amplitude-timing errors, how pulse array balances switching to avoid them, and why DAVE needs 350 dB noise shapers for depth. Head-Fi, May 2016
• 2016-05-17Watts says DAVE's DAC mode equals pre-amp mode with volume fixed at -3 dB (3 V RMS), and DAVE clips only above +4 dB, which gives 6.7 V RMS. Head-Fi, May 2016
• 2016-05-21Watts says brain break-in matters far more than hardware break-in, DAVE's FPGA must be soldered rather than socketed, a replacement is years away, and code updates need significant gains. Head-Fi, May 2016
• 2016-05-21Watts says DAVE's DX output sends 705/768 kHz 24-bit at full level, carrying the volume setting and a DX identifier in user data for the DX power amp. Head-Fi, May 2016
• 2016-05-23Watts says he uses Mojo while traveling and sets up DAVE in hotels, where from cold its sound quality reaches full form within about 10 minutes. Head-Fi, May 2016
• 2016-05-24Watts says all his DACs replace an op-amp's output stage with a discrete Class A stage inside one feedback loop, and DAVE adds a second-order analog noise shaper. Head-Fi, May 2016
• 2016-05-30Watts recalls using dither with multiple DSD256 noise shapers on the PDM1024 in 1992, says the pulse array made it unnecessary, and notes dither cannot be added to DSD directly. Head-Fi, May 2016
• 2016-05-30Watts says a DAVE code update would require return to a trained distributor or Chord, would not be done for minor changes, and a new DAVE has arrived. Head-Fi, May 2016
• 2016-05-31Watts says setup took him many wasted hours, only to find DSD512 still sounds poorer than Red Book on DAVE. needs context Head-Fi, May 2016
• 2016-05-31Watts gives two reasons adding noise to zero bits can help a DAC, small-signal non-linearity and signal-correlated DSP supply noise, and says DAVE's 350 dB noise shapers justify re-testing it. Head-Fi, May 2016
• 2016-05-31Watts confirms a DX output works into a dual BNC input, since two DAVEs can be cascaded that way. Head-Fi, May 2016
• 2016-06-02Watts says DAVE sounded too dark and soft late in development until a 256FS WTA stage improved perception of note starts and stops and restored balance. Head-Fi, Jun 2016
• 2016-06-04Watts says WTA1 uses 90% of DAVE's FPGA DSP, so a power amp fed 16FS data could use a bigger WTA2; the DAVE power amp will outpower the Hugo amp. Head-Fi, Jun 2016
• 2016-06-06Watts says his ADC plus DAVE at 768 kHz could beat an analog pre-amp, and describes a WTA FIR decimation filter from 104 MHz to 768 kHz for two prototypes. Head-Fi, Jun 2016
• 2016-06-08Watts says a DAVE sound-quality code update may never be needed, is being considered only for 768 kHz use with Davina, and would come no earlier than 2017. Head-Fi, Jun 2016
• 2016-06-15Watts says a careful AB test might reveal a small, musically unimportant difference due only to extra earthing, and DAVE won't mind the tiny extra loading. needs context Head-Fi, Jun 2016
• 2016-06-16Watts doubts DAVE has significant hardware break-in, lists causes such as bias drift, electrolytic capacitors and RF noise, and says every DAVE measures about -127 dB THD and noise. Head-Fi, Jun 2016
• 2016-06-17Watts says DAVE is fully DC coupled with no coupling capacitors, using a digitally filtered DC servo, with only small polypropylene filter capacitors in the signal path. Head-Fi, Jun 2016
• 2016-06-17Watts compares electrolytic, tantalum and film coupling capacitors and describes DAVE's digital DC servo, which stores its trim in flash and causes a 20-second turn-on delay. Head-Fi, Jun 2016
• 2016-06-18Watts recounts moving from word clocks and the DAC64's buffer to a DPLL perfected over six or seven years, and says word clocks would now be a backward step. Head-Fi, Jun 2016
• 2016-06-21Watts says DAVE's USB isolation leaves 2 pF coupling, about 79 ohms at 1 GHz, and plans a JitterBug test to find whether laptop RF arrives via mains or USB. Head-Fi, Jun 2016
• 2016-06-27Watts reports a JitterBug lifted DAVE with a mains-powered laptop from 0% to 75% but made no difference on battery, concluding RF couples mainly via USB. Head-Fi, Jun 2016
• 2016-06-27Watts plans to try a microRendu, saying reported smoothness suggests lower RF noise, though a battery source with no earth ought to inject the least RF into DAVE. Head-Fi, Jun 2016
• 2016-06-28Watts says airborne RF is no problem for DAVE because its machined aluminum case screens it, while mains and I/O connections are carefully RF filtered. Head-Fi, Jun 2016
• 2016-06-28Watts says blocking some of DAVE's holes is fine, but covering them with something not thermally conducting reduces its heat dissipation. Head-Fi, Jun 2016
• 2016-06-28Watts says DAVE's output stage and second-order noise shaper came from his digital power amp, a more powerful DAVE whose output is linear, not Class D switching. Head-Fi, Jun 2016
• 2016-06-29Watts says DAVE's USB is timed by its own clock, while other inputs use his DPLL, actually frequency-locked with a tiny buffer, so source jitter cannot reach the output. Head-Fi, Jun 2016
• 2016-07-09Watts finds a new DAVE slightly brighter and more transparent than his pre-production unit, credits nitrogen production soldering, and says brain break-in outweighs physical break-in. Head-Fi, Jul 2016
• 2016-07-09Watts describes brain break-in as gradually improving perceived depth and note starts and stops, citing depth returning a month after adding a bookshelf, while smoothness changes are hardware. Head-Fi, Jul 2016
• 2016-07-09Watts says final DAVE production PCBs were made in spring 2015, the production BOM released that summer, and code finished in December before serial production. Head-Fi, Jul 2016
• 2016-07-13Watts says DAVE's handbook has a typo: output impedance is 0.055 ohms at the headphone output, though the damping factor is correct. Head-Fi, Jul 2016
• 2016-07-18Watts explains how source RF couples into DAVE through the USB isolator's 2 pF capacitance and ground plane, raising noise floor modulation, and why a battery-powered laptop avoids it. Head-Fi, Jul 2016
• 2016-07-18Watts says audibility depends on the DAC: unlikely with DAVE or a battery source, but an SSD may help DACs lacking USB galvanic isolation or PSU RF filtering. needs context Head-Fi, Jul 2016
• 2016-07-19Watts says lifting the ground does not help since the loop then runs through the neutral of the laptop and DAVE supplies, and isolation transformers have high coupling capacitance. Head-Fi, Jul 2016
• 2016-07-23Watts says another galvanic isolator won't help DAVE, a JitterBug gets to 99.75%, and isolated USB now edges optical in detail and flow because its clock comes from DAVE. Head-Fi, Jul 2016
• 2016-07-24Watts explains DAVE stands for Digital Analogue Veritas in Extremis, aiming for maximum transparency, and says so-called transparent products often sound hard and bright, giving an impression of detail. Hifistatement 0
• 2016-07-24Watts says a second factor behind DAVE was the unexpected quality he heard from Hugo, whose internal digital modules had been upgraded over a 6 year period. Hifistatement 32
• 2016-07-24Watts says a major code rewrite, with more powerful simulation tools, was intended for a planned reference DAC; he made Hugo for hotel listening, expecting few sales. Hifistatement 1:17
• 2016-07-24Watts says Hugo was a personal project while he did silicon design work in Phoenix; code developed for the reference product went into Hugo, the first product using it. Hifistatement 2:03
• 2016-07-24Watts says Hugo's quality came from perceiving the starting and stopping of transients, not the WTA filter, since earlier 32,000-tap filters lacked it (Hugo had 26,000); DAVE gets bigger FPGAs. Hifistatement 3:31
• 2016-07-24Watts says Hugo is cost constrained while DAVE's FPGA is 10 times larger, allowing longer taps, bigger WTA filters, more advanced noise shapers and a better discrete pulse array DAC. Hifistatement 4:16
• 2016-07-24Watts says Hugo has about 26,000 taps, Mojo similar, and DAVE 164,000 taps on 166 DSP cores filtering to 2048 times; the 100,000-line WTA code repeatedly failed timing closure. Hifistatement 3:15
• 2016-07-24Watts says the DAVE filter took nine months to work on the FPGA, and was better but lacked Hugo's starting and stopping of notes, speed and timbre variation. Hifistatement 4:02
• 2016-07-24Watts says for DAVE he raised noise shaper performance from Hugo's 200 dB through 220, 240 and 260 dB, depth improving each time, reaching -350 dB over 90 days. Hifistatement 3:05
• 2016-07-24Watts says the brain detects tiny errors as poorer instrument placement, depth needs perfect accuracy, and he ended with a new 17th-order noise shaper with 46 integrators. Hifistatement 3:54
• 2016-07-24Watts says the highest-order noise shaper he had seen was 9th order or DSD, and he worried that the 350 dB gains might be a proxy for some analog-domain effect. Hifistatement 4:40
• 2016-07-24Watts says redesigning DAVE's all-digital noise shapers to 350 dB gave the same results, so the digital path truly needs 350 dB (48-bit) accuracy; it is not a proxy. Hifistatement 5:24
• 2016-07-24Watts says better 2048FS filtering on Hugo also improved timing resolution, so in place of Hugo's 8x-then-16x WTA stages he tried a single 16x WTA stage, which sounded a lot better. Hifistatement 6:51
• 2016-07-24Watts says this mattered more than going from 26 thousand to 164 thousand taps, 16x filtering is accurate only to microseconds, and he added a 16x-to-256x WTA stage. Hifistatement 7:47
• 2016-07-24Watts says the FIR filter now runs at 256 times FS, beyond others' 16 times (he once did 32), using many DSP cores and making a massive change. Hifistatement 8:32
• 2016-07-24Watts says Hugo cannot be improved because its FPGA is too small, its design is optimal for that device, and DAVE's 16FS and 256FS gains came from far more processing. Hifistatement 10:57
• 2016-07-24Watts says analog and noise shaper improvements made DAVE almost too rich and soft, lacking Hugo's immediacy, until improved WTA filters and other changes made it faster, tighter, more dynamic and more neutral. Hifistatement 11:45
• 2016-07-24Watts says the DAC is now faster, more transparent and dynamic yet richer; he aims for transparency, not a sound, and won't re-optimize his own system for it. Hifistatement 12:26
• 2016-07-24Watts says Hugo's sound hardened slightly into very low impedance headphones, with higher-order harmonics measurable; since an analog amplifier is a first-order noise shaper, he took a second-order approach. Hifistatement 0
• 2016-07-24Watts says Cordell's 1980s nested feedback loops failed on stability because they were treated as amplifiers; treating the stage as a second-order noise shaper let him solve stability easily. Hifistatement 43
• 2016-07-24Watts says the analog noise shaper output stage removed the distortion problem: into 33 ohms only second harmonic rises slightly, with one global feedback path and minimal analog filtering. Hifistatement 1:30
• 2016-07-24Watts says this means very simple analog circuitry. needs context Hifistatement 2:17
• 2016-07-24Watts explains that a local feedback loop corrects output-stage distortion inside one global feedback loop from the DAC's current output, which sets the gain, so the stage behaves as distortion-free. Hifistatement 2:27
• 2016-07-24Watts likens the output stage to a noise shaper with one global feedback path, and says the music envelope modulates the output flip-flops' reference power, changing the gain. Hifistatement 3:20
• 2016-07-24Watts says reference modulation is not measurable but very audible; his reference has 0.5 of a milliohm impedance to each flip-flop; a digital DC servo removes coupling capacitors and offset. Hifistatement 4:13
• 2016-07-24Watts says the offset is below fifty microvolts and the headphone drive delivers 6 volts and half an amp of output current. Hifistatement 5:02
• 2016-07-24Watts lists DAVE's measured performance: distortion and noise 124 dB A-weighted at 5 volts, minus 127 dB at 2.5 volts, dynamic range minus 127 dB, distortion 0.000015%. Hifistatement 0
• 2016-07-24Watts says his DACs from Mojo to DAVE show no measurable noise floor modulation or anharmonic distortion, with distortion falling as signal falls, unlike R2R, DSD and silicon DACs. Hifistatement 44
• 2016-07-24Watts says the APx555, out the previous November, is the only equipment able to measure DAVE, which nears its levels; he cannot say how much is DAVE versus the AP. Hifistatement 0
• 2016-07-24Watts says DAVE's harmonics are below -150 dB and noise floor -180 dB, unchanged with no signal or 2.5 volts output; he says noise floor modulation sounds brighter and harder. Hifistatement 22
• 2016-07-24Watts says fully isolating DAVE from a USB source needs the source free of earth and mains cables, so he uses portable hard disks, and wireless should be fine. Head-Fi, Jul 2016
• 2016-07-27Watts says DAVE's first prototype PCB was designed over three years earlier, when the FPGA was chosen on price and availability, and knowledge matters more than FPGA size. Head-Fi, Jul 2016
• 2016-08-01Watts says DAVE's crossfeed is mathematically identical to 1980s analog crossfeed, DAVE adds no reverb, and he recommends hearing it at home since show listening is less sensitive. Head-Fi, Aug 2016
• 2016-08-02Watts says he is unaware of any audible noise when DAVE's display is active. Head-Fi, Aug 2016
• 2016-08-05Watts describes DAVE's power system: multistage RF filtering, a 3 milliohm output-stage supply and a discrete reference under 0.1 milliohm; he says noise floor modulation is audible to -200 dB. Head-Fi, Aug 2016
• 2016-08-07Watts says MQA is still under evaluation, and that DAVE's FPGA and spare expansion connector would let Chord support future developments if they credibly improved sound quality. Head-Fi, Aug 2016
• 2016-08-09Watts explains why a PC cannot replicate DAVE's processing: FPGAs run filter taps in parallel (DAVE 166 DSP cores, Mojo 44 at 0.45 W), and algorithm design also matters. Head-Fi, Aug 2016
• 2016-08-10Watts says player differences depend on DAC isolation, OS and program; Chord's Windows driver resends errored packets, and with DAVE on a battery laptop he expects no differences. Head-Fi, Aug 2016
• 2016-08-10Watts confirms that 2Qute, Hugo TT and DAVE share the same USB decoder and galvanic isolation. Head-Fi, Aug 2016
• 2016-08-14Watts says DAVE's switch-mode supply works from 90 to 263 V and 47 to 440 Hz, so DAVE sounds the same on mains in Japan, the US, UK and Europe. Head-Fi, Aug 2016
• 2016-08-19Watts hypothesizes that brain break-in, first noticed with Hugo, is the brain unlearning coping strategies for sampled-data timing errors, which DAVE showed must be accurate to nanoseconds. Head-Fi, Aug 2016
• 2016-08-28Watts compares DAVE and Mojo: 1% output into 300 ohms 6.8 V vs 5.4 V, THD+N at 3 V 0.00009% vs 0.00017%, THD at 2.5 V 0.000007% vs 0.0001%. Head-Fi, Aug 2016
• 2016-08-28Watts says DAVE's USB 5 V is isolated, and battery-laptop or USB-vs-optical differences are tiny; optical gives full RF isolation, USB slightly better timing from DAVE's clock. Head-Fi, Aug 2016
• 2016-08-29Watts says a small chassis is beneficial, giving better RF filtering, shorter path lengths and vibration control on a solid aluminum block, and recalls no compromises from the size. Head-Fi, Aug 2016
• 2016-09-01Watts explains DAVE's output amplifier is a second-order analog noise shaper, so loading barely changes distortion and HF distortion stays low (1 GHz gain-bandwidth), citing 19k/20k test results. Head-Fi, Sep 2016
• 2016-09-04Watts recalls using multiple dithered noise shapers for DSD256 in the early 1990s, explains that his 1995 pulse array eliminates correlated jitter, and why discrete flip-flops beat on-chip shift registers. Head-Fi, Sep 2016
• 2016-09-05Watts says DAVE lets each recording sound as it is rather than imposing a fixed signature, and asks whether others find DAVE makes differences between headphones more pronounced. Head-Fi, Sep 2016
• 2016-09-07Watts says DAVE is very slightly microphonic, suggests vibration may add low-frequency jitter skirts that sound hard, and says femto clocks add skirts and brightness mistaken for transparency. Head-Fi, Sep 2016
• 2016-09-13Watts clarifies that the -350 dB figure is the noise shaper's exact Verilog-simulated digital performance, mattering for preserving tiny signal amplitudes rather than noise, which he ties to depth. Head-Fi, Sep 2016
• 2016-09-14Watts describes running three DAVE systems, including portable hotel speakers, and says DAVE usually works in demo systems but occasionally sounds flat and hard until setup is fixed. Head-Fi, Sep 2016
• 2016-09-14Watts says display blanking when settings are saved is normal because flash memory cannot be read while being written, and refers a remote problem to the dealer. Head-Fi, Sep 2016
• 2016-09-14Watts admits he cannot explain why depth needs 350 dB noise shapers, gives a -120 dB signal's attenuation for 160 to 340 dB shapers, yet still hears the change. Head-Fi, Sep 2016
• 2016-09-16Watts reports no consistent difference between ASIO and WASAPI with DAVE from his design laptop on battery, using a 96k 24-bit Hildegard von Bingen recording. Head-Fi, Sep 2016
• 2016-09-17Watts says the amplifier project was delayed by other projects, that DAVE's output stage came from it, and that its prototype must be redone but is planned for 2017. Head-Fi, Sep 2016
• 2016-09-25Watts explains why DAVE uses his DPLL rather than the DAC64/QBD76 buffer, word clocks or an external master clock: PLLs add low-frequency jitter, causing FFT fringing and brightness. Head-Fi, Sep 2016
• 2016-09-26Watts points to DAVE's J-test, where skirting at -160 dB spans about +/- 20 Hz, about 1 pS of 20 Hz jitter, dominated by the APx555; worse skirting sounds brighter. Head-Fi, Sep 2016
• 2016-10-01Watts says he loves the NightHawks for speaker-like tonal balance and low distortion, and found the Focal Utopia driven by DAVE very good in five minutes at the Tokyo show. Head-Fi, Oct 2016
• 2016-10-16Watts argues musicality comes first and explains why Mojo and DAVE excel on transient timing (NOS errors, tap length, 1M taps), small-signal accuracy and noise floor modulation. Head-Fi, Oct 2016
• 2016-10-20Watts lists the filter stages: Hugo and Mojo use WTA 16FS, linear interpolation to 2048FS and 260 kHz low-pass filters; DAVE adds a WTA stage to 256FS, nearer ideal sinc. Head-Fi, Oct 2016
• 2016-10-20Watts shows an FFT of DAVE's noise shaper output resolving a -301 dB 6 kHz signal, stands by his listening-based claim that depth needs this, and plans Davina tests. Head-Fi, Oct 2016
• 2016-10-21Watts says DAVE risks headphone clipping only at +5 dB volume, and a 33-ohm load does not harden its sound, owing to the second-order noise shaper and discrete output stage. Head-Fi, Oct 2016
• 2016-10-21Watts explains DAVE's 20-element pulse array feeds current into a single I-to-V converter rather than using voltage mode, and why keeping the node and reference voltage noise-free was hard. Head-Fi, Oct 2016
• 2016-10-21Watts says adding the 256FS WTA filter turned DAVE from rich, dark and almost soft to sharper and tighter, improving starting and stopping of notes by nearing ideal sinc. Head-Fi, Oct 2016
• 2016-10-27Watts says two power amps can be used, hence four DX outputs, and plans a volume trim on the amps in DX mode since master volume is sent digitally. Head-Fi, Oct 2016
• 2016-10-28Watts says Chord's new remote works like the old one, and expects reversing the Schuko plug to make no difference as DAVE is transformer coupled; warmer would mean less RF. Head-Fi, Oct 2016
• 2016-10-28Watts says DAVE sounds great out of the box, otherwise taste or a flawed system is to blame; it highlights headphone differences, and listeners should question their own impressions. Head-Fi, Oct 2016
• 2016-11-01Watts says his reward is enjoying music with Mojo and DAVE, and blames himself for Blu Mk2's delay: the August prototype worked, but an improvement cost two or three months. Head-Fi, Nov 2016
• 2016-11-01Watts says Blu Mk2's optical output reaches only 176.4 kHz, so 705.6 kHz reaches DAVE via dual BNC, whose outputs are RF isolated with optional full galvanic isolation. Head-Fi, Nov 2016
• 2016-11-10Watts says DAVE's depth comes from preserving small-signal amplitudes, not its -128 dB noise floor; timbre from no noise floor modulation and accurate transient timing; hard USB from non-bit-perfect data. Head-Fi, Nov 2016
• 2016-11-10Watts answers no to two questions and says DAVE 2 has not even been dreamed about and is many years away unless essential parts become unavailable. Head-Fi, Nov 2016
• 2016-11-16Watts says live music has far more depth, dry close-miked vocals should sound flat on DAVE, which focuses vocals tightly and tolerates wider speaker spacing than TT. Head-Fi, Nov 2016
• 2016-11-19Watts says it can be done on BNC inputs but not DX outputs, without sonic benefit, as pull-ups keep unused BNC inputs inactive and their ground joins the ground plane. needs context Head-Fi, Nov 2016
• 2016-11-21Watts says that to prevent accidental mode switching, the right or left button must be held for at least one second after the plus menu is selected. Head-Fi, Nov 2016
• 2016-11-28Watts says switching from PCM+ to DSD+ over USB resets the USB device, so close the media player, change mode and restart it to avoid an unstable state. Head-Fi, Nov 2016
• 2016-12-08Watts confirms it is grounded via a wire to the aluminum chassis block, with each spacer connecting the chassis to the PCB ground planes. Head-Fi, Dec 2016
• 2016-12-11Watts says a 33-ohm load barely changes DAVE's THD+N (-127 to -124 dB), and argues a wider soundstage usually signals lost depth and transparency, except where recordings encode out-of-the-box cues. Head-Fi, Dec 2016
• 2016-12-12Watts says DAVE drives the 46-ohm Abyss linearly up to +4 dB, explains how its 0.055-ohm output impedance tightens bass and cuts load distortion, and suggests EQ rather than distortion. Head-Fi, Dec 2016
• 2016-12-18Watts says ASIO and WASAPI are both bit perfect; DAVE shows no difference via isolation and battery laptop, yet ASIO sounds slightly better on Mojo, likely from less processor noise. Head-Fi, Dec 2016
• 2016-12-18Watts gives the output impedance as 0.055 ohm on the single-ended phono and headphone outputs and 33 ohms on XLR, saying lower impedance makes interconnect dielectric less audible. Head-Fi, Dec 2016
• 2016-12-21Watts says the Remedy's cheap TI SRC chip is not bit perfect, adds distortion, noise and timing errors, and is possibly the fastest way to destroy Mojo or Dave's sound. Head-Fi, Dec 2016
• 2017-01-07Watts presents the Blu Mk2 slides: why ringing worries are mistaken, the 16-bit case for about 1M taps, delaying launch to reach 1M, and why the scaler is separate. Head-Fi, Jan 2017
• 2017-01-08Watts says Davina's bi-directional USB can send 768 kHz M scaler output to a PC, but Dave is meant to receive 768 kHz via isolated BNC, as with Blu Mk2. Head-Fi, Jan 2017
• 2017-01-08Watts says the M scaler outputs any multiple of the input rate, benefiting DAVE most through its 256FS and 2048FS filtering; other DACs improve by an amount he cannot say. Head-Fi, Jan 2017
• 2017-01-08Watts says Blu got the M scaler first because Chord still sells Blu and Dave out-tapped Blu 1; the work feeds Davina, and he travels with Blu and Dave. Head-Fi, Jan 2017
• 2017-01-09Watts says he uses Hugo 2 on planes and Dave with the M scaler in hotels; Hugo 2 should ship late February or early March and appear at CanJam Singapore. Head-Fi, Jan 2017
• 2017-01-09Watts says WTA processing is identical from 44.1 to 384 kHz, explains mounting the FPGA core switching regulator underneath to limit ground-plane noise, and Blu Mk2 needing 12A. Head-Fi, Jan 2017
• 2017-01-09Watts explains Dave's 16FS-to-256FS WTA stage replacing IIR filters, says any timing error is audible, notes Hugo 2 filter settings switch that stage, and contrasts 88 nS with 2.6 uS. Head-Fi, Jan 2017
• 2017-01-09Watts says 384/24 is distinguishable from 48/24 but recording method matters more, praises 1960s Decca recordings, calls the M scaler 'a great equalizer', and says Davina will measure losses. Head-Fi, Jan 2017
• 2017-01-09Watts says listeners find the M scaler a bigger change than Dave, believes on another DAC it would be an ordinary tap-length gain, and wonders why sixfold taps transform sound. Head-Fi, Jan 2017
• 2017-01-09Watts confirms a poster is correct about the M scaler and Dave delay. needs context Head-Fi, Jan 2017
• 2017-01-15Watts recounts M scaler development and CES demos, discusses judging the scale of changes, lists gains in timbre, bass pitch and depth, and describes improving stop-band rejection. Head-Fi, Jan 2017
• 2017-01-23Watts says Hugo 2's 256FS filter matches Dave's, and the HF filter is best off with the M scaler and Dave since stop-band rejection is already 130 to 150 dB. Head-Fi, Jan 2017
• 2017-01-23Watts says Dave's 26,000 to 164,000 tap step disappointed him, algorithm and 16FS mattered more, 0.5M taps was transformational, and explains reducing errors until inaudible with a biscuit-barrel analogy. Head-Fi, Jan 2017
• 2017-01-23Watts says the 256FS filter improves starts and stops of notes, Hugo cascaded two WTA stages while Dave uses one, and Dave remains well above Hugo 2. Head-Fi, Jan 2017
• 2017-01-29Watts says Dave's DX outputs will feed his digital-input power amps, with one global feedback loop, 4 passive parts, a third-order noise-shaper structure and non-switching output; first model 20W. Head-Fi, Jan 2017
• 2017-02-01Watts says the M scaler connects to Dave's dual BNC inputs (1 and 2 or 3 and 4); DX outputs are dual BNC 705/768 kHz SPDIF carrying volume data. Head-Fi, Feb 2017
• 2017-02-05Watts says he tried four USB cables from 3 USD to 300 USD and could not reliably hear a difference with Dave. Head-Fi, Feb 2017
• 2017-02-05Watts says his USB cable tests used headphones only, cable RF may affect pre-amps and power amps, and early differences vanished when he separated the USB and headphone cables. Head-Fi, Feb 2017
• 2017-02-05Watts says Dave driving valve power amps directly has always sounded superb and more transparent without a pre-amp, and suggests the 33 ohm balanced outputs if an amp goes unstable. Head-Fi, Feb 2017
• 2017-02-06Watts says he uses ordinary active computer speakers, is looking for portable passive speakers to drive directly from DAVE, and uses AQ NightHawks for serious listening. Head-Fi, Feb 2017
• 2017-02-07Watts says PC upsampling has limited taps and conventional algorithms, converting to DSD degrades depth and timing, and data to Mojo, Hugo or Dave should stay bit perfect. Head-Fi, Feb 2017
• 2017-02-20Watts explains how rail currents through PSU impedance and limited PSRR cause distortion and bass smear, why DAVE uses milliohm supplies and high PSRR, and why big supplies miss this. Head-Fi, Feb 2017
• 2017-02-20Watts says DX is AES dual-data SPDIF with volume in user data; Mojo takes 768 only via USB, coax tops at 384 kHz, and Hugo 2 now accepts dual-data coax. Head-Fi, Feb 2017
• 2017-03-04Watts says his cable work showed oxides cause small-signal non-linearity that harms depth yet is unmeasurable, and DAVE noise-shaper tests show any small-signal error is audible. Head-Fi, Mar 2017
• 2017-03-05Watts cautions one laptop test proves little: Hugo 1 improved enormously with isolation from a Dell PC, while galvanic isolation on production Blu 2 with DAVE gives a substantial improvement. Head-Fi, Mar 2017
• 2017-03-15Watts posts his CanJam Singapore Hugo 2 slides: WTA2 to 256FS, filter options and advice, DSD filtering, noise shapers and depth, crossfeed, and APx555 measurements showing no noise floor modulation. Head-Fi, Mar 2017
• 2017-03-15Watts confirms a poster's filter definition and their point about the HF filter on DAVE. needs context Head-Fi, Mar 2017
• 2017-03-19Watts says Hugo 2's 'Mojo filter' only selects a 16FS WTA with Mojo-like tonal balance, and the 256FS filter gives DAVE-like incisiveness without making Hugo 2 sound like DAVE. Head-Fi, Mar 2017
• 2017-03-26Watts says this was largely already in Mojo, Hugo 2 has better PSU isolation, and he will re-run tests with Mojo, Hugo 2 and DAVE after a surprising result. needs context Head-Fi, Mar 2017
• 2017-04-07Watts says Hugo 2 with the white filter has a tonal balance like his DAVE and M scaler reference, avoids hardness, and the 16FS filter suits hard headphones. Head-Fi, Apr 2017
• 2017-04-12Watts says Hugo 2's crossfeed code is identical to DAVE's PCM+ crossfeed. Head-Fi, Apr 2017
• 2017-04-13Watts links 'strobing' impressions to hearing note starts and stops via the 256FS WTA, contrasting his son's live guitar with a soft CD playback, and wants both speed and warmth. Head-Fi, Apr 2017
• 2017-05-01Watts describes Jude recognizing the M scaler at the Tokyo show despite unfamiliar headphones, says its effect is audible even on unfamiliar recordings, and that it simply sounds real. Head-Fi, May 2017
• 2017-05-02Watts says Dave took over 2 man years and he will not repeat that now, as Davina and the amps, to be called Power Pulse Array, will occupy years. Head-Fi, May 2017
• 2017-05-02Watts says the amp is mostly for driving speakers from Dave's DX outputs, though a few headphones would appreciate the power. Head-Fi, May 2017
• 2017-05-08Watts says the M scaler is 0.234 dB louder (-2.766 dB insertion loss, +3 dB volume) and its 10 A signal-dependent FPGA ground current forces a separate, isolated box. Head-Fi, May 2017
• 2017-05-12Watts says a remeasured DAVE was perfect on an APx555, suspects aliasing in JA's analyzer ADCs, and says Davina has zero noise floor modulation and around 15 dB less noise. Head-Fi, May 2017
• 2017-06-04Watts says Hugo TT's remote decoding was not his design, Hugo 2 decodes it in the FPGA, and DAVE uses the same FPGA implementation with different codes and never misfires. Head-Fi, Jun 2017
• 2017-06-10Watts says a native 768 kHz test recording from Chord's Japanese distributor sounded like M-scaled playback, unlike DXD so far, though its high ADC noise made DAVE's HF filter matter. Head-Fi, Jun 2017
• 2017-06-10Watts flatly rejects the claim that the QBD76 is better than DAVE, saying DAVE hugely beats it in every regard. Head-Fi, Jun 2017
• 2017-06-11Watts says DAVE sounds better via the M scaler not from a WTA fault, citing Verilog simulation and -301 dB tests, and video mode's two-thirds million taps shrinks the soundstage. Head-Fi, Jun 2017
• 2017-06-13Watts says he takes his DAVE on travels even without shows, the risk being scratches rather than failure, and that it has covered a quarter million miles. Head-Fi, Jun 2017
• 2017-06-14Watts says that with DAVE, and more so DAVE with the M scaler, differences between headphones grow and rankings shift unpredictably. Head-Fi, Jun 2017
• 2017-06-18Watts says Hugo 2's digital DC servo keeps bass flat with crossfeed off, and APx555 peak measurements show 20 Hz to 1 kHz flat within 0.001 dB; DAVE is identical. Head-Fi, Jun 2017
• 2017-06-18Watts says he did not tweak Hugo 2's frequency response, and that DAVE is a very big step up in clarity and sounds brighter overall due to its transparency. Head-Fi, Jun 2017
• 2017-06-21Watts describes airport X-ray checks of his roughly 20 kg carry-on of DAVE, Blu 2 and two laptops, saying only London Heathrow stops and swabs him every time. Head-Fi, Jun 2017
• 2017-06-26Watts recounts his DAC history since 1988 and how Hugo, from 2012, made poor recordings musically involving, which he attributes to the ear's sensitivity to reconstruction timing errors. Head-Fi, Jun 2017
• 2017-06-27Watts says with DAVE bad headphones became very bad and good ones much better, since greater transparency exposes transducer strengths and deficiencies. Head-Fi, Jun 2017
• 2017-07-02Watts says Power Pulse Array prototypes are being built with no realistic timeline, release waits until he is satisfied, and DAVE driving small speakers directly gives stunning depth. Head-Fi, Jul 2017
• 2017-07-09Watts says he has a production pair of Aeons, finds them exceptionally good, and calls them a good match for Mojo, Hugo 2 and DAVE. Head-Fi, Jul 2017
• 2017-08-03Watts says +4 dB volume is fine with DAVE on its own. Head-Fi, Aug 2017
• 2017-08-03Watts says material peaking at -1 dBFS allows +5 dB on DAVE without clipping, but sources reaching 0 dBFS will clip. Head-Fi, Aug 2017
• 2017-08-10Watts notes Benchmark's website omits galvanic isolation, disputes that Hugo 1 sounds different, praises its musicality with archive recordings, and says 1960s Decca sounds real via Blu 2 and DAVE. Head-Fi, Aug 2017
• 2017-08-11Watts says the million-tap M scaler exceeds 16-bit accuracy, Hugo 2 takes 768 kHz dual BNC, better analog parts put DAVE ahead, and he flies with DAVE and Blu 2. Head-Fi, Aug 2017
• 2017-08-11Watts says Davina will match DAVE in size and be comparable in price, and that he awaits its prototype; he also says native DSD's timing errors and poor small-signal resolution make it soft and flat. Head-Fi, Aug 2017
• 2017-08-17Watts says chip DACs suffer noise floor modulation, jitter sensitivity, poor small-signal resolution and short filters versus Hugo 2's 49,152 taps, factors far outweighing passive part quality. Head-Fi, Aug 2017
• 2017-08-18Watts describes a Tokyo show system (DAVE, SPM1200, B&W 803 D3) as the best outside his home, then reports buying 803 D3s to replace his Velour speakers and recommends them. Head-Fi, Aug 2017
• 2017-08-22Watts identifies an early-1990s design of his, the DPA 200S with a thick-film hybrid Class A amplifier, but says no analog amplifier matches DAVE driving small speakers directly for depth. Head-Fi, Aug 2017
• 2017-09-05Watts says he runs DAVE directly into 88 dB/1W small speakers in his office with plenty of volume and better soundstage depth than his main system. Head-Fi, Sep 2017
• 2017-09-06Watts says a summing Y connector made of a resistor pair mixing stereo to mono would be fine, because Hugo 2 and DAVE have very low output impedance. Head-Fi, Sep 2017
• 2017-09-06Watts says the AudioQuest site gives little detail; he fears the adaptor shorts left and right together, giving mono at best and damaging Hugo 2 or DAVE at worst. needs context Head-Fi, Sep 2017
• 2017-09-09Watts says Hugo 2's crossfeed code is unchanged from Hugo, but better depth makes crossfeed have a big impact on perceived depth, as also happens with Dave. Head-Fi, Sep 2017
• 2017-10-02Watts says he hears no difference between USB cables on DAVE, optical versus USB is minute, and a battery source via DAVE's isolated USB isolates better than mains-powered optical. Head-Fi, Oct 2017
• 2017-10-11Watts says WTA reconstructs transients regardless of origin; DAVE's 164,000-tap delay is about 0.2 s and 1M taps 1.4 s, and his RT60 explanation for depth is speculative. Head-Fi, Oct 2017
• 2017-10-11Watts says aliasing from modern ADCs' half-band filters (-6 dB at FS/2) is irreparable, yet every track in his 5 TB library sounds better on BluDave with longer taps. Head-Fi, Oct 2017
• 2017-10-13Watts says tap length is crucial and, with Moore's Law, tap counts rose: DAC64 1,000, QBD76 18,000, Hugo 26,000 and DAVE 164,000. miceblue425 22:51
• 2017-10-13Watts says in DAVE's development he started from Hugo's 26,000-tap filter and designed a 164,000-tap one; two designs failed timing closure, which he explains. miceblue425 28:44
• 2017-10-13Watts says the DAVE filter took nine months and sounded only a bit better, so he expected little from the M Scaler and first built an easy half-million-tap version. miceblue425 29:37
• 2017-10-13Watts says the 512,000-tap filter compared with DAVE gave his biggest shock in 5 years, partly due to an improved WTA filter and moving from 8FS to 16FS. miceblue425 30:21
• 2017-10-13Watts says DAVE's noise shapers needed 350 dB accuracy to preserve small signals, that 330 versus 350 dB is still audible, and that Davina's noise shapers reach 360 dB. miceblue425 37:35
• 2017-10-16Watts posts seminar measurement slides, saying simulation shows -301 dB signals reproduced, his designs have no measurable noise floor modulation, and jitter FFTs should replace marketing claims. Head-Fi, Oct 2017
• 2017-10-20Watts lists WTA tap lengths (DAC64 a thousand, QBD76 18 thousand, Hugo 26,000, DAVE 164,000) and says each increase improved bass definition, timbre, staging precision and note starts and stops. Hifistatement 0
• 2017-10-20Watts says he did not expect a big sonic change from this project; moving DAVE from 26,000 to 164,000 taps took nine months and 3 redesigns over timing closure. Hifistatement 2:10
• 2017-10-20Watts explains timing closure (nets within 4.8 nanoseconds on this design), says DAVE's filter was redesigned twice to achieve it, and after nine months it sounded only a bit better. Hifistatement 2:52
• 2017-10-20Watts says longer taps improved bass definition, timbre and pitch as usual, but the million-tap M Scaler also opened up depth and soundstage beyond DAVE's. Hifistatement 2:03
• 2017-10-20Watts says the USB video mode, two-thirds of a million taps on the same architecture, collapses the soundstage, though architecture and small-signal work carried over from DAVE also matter. Hifistatement 2:57
• 2017-10-20Watts says the 200T FPGA draws 10 A processing versus 2 A idle, so it sits in a galvanically isolated Blu 2 rather than DAVE, keeping DAVE's ground plane clean. Hifistatement 0
• 2017-10-20Watts says sinc ripples drop below 16-bit level near a million taps; doubling adds 1 bit. DAVE is about 13 bits, Blu beyond 16, NOS 1, MQA 3 or 4. Hifistatement 24
• 2017-10-20Watts rates a typical high-performance DAC at 6 or 7 bits accurate, Hugo 12, DAVE 13.5, Blu beyond 16, and says ringing is irrelevant because it comes from non-bandlimited impulses. Hifistatement 1:12
• 2017-10-22Watts says CPUs struggle even with DSD512 DoP, 'input related' tap figures are meaningless pseudo numbers, cascaded FIR stages differ from one flat stage, and only real taps count. Head-Fi, Oct 2017
• 2017-10-24Watts suggests using DAVE's balanced output and its volume control to avoid driving the ADAM speakers with too high a voltage. Head-Fi, Oct 2017
• 2017-10-25Watts says DAVE's data path from input to pulse array is better than 350 dB, so no truncation occurs and large volume changes do not affect detail or depth. Head-Fi, Oct 2017
• 2017-10-28Watts says going from Hugo's 26k to DAVE's 164k taps changed little until WTA algorithm tweaks did; for a given algorithm, doubling taps doubles accuracy against the ideal. Head-Fi, Oct 2017
• 2017-10-31Watts says DAVE at -3 dB gives 3 V RMS, -10 dB gives 1.34 V RMS, and setting -6 on the display gives about 2.1 V maximum. Head-Fi, Oct 2017
• 2017-11-29Watts says USB cables sound identical or, if audiophile, add RF, brightness and noise floor modulation; USB ferrites did nothing, but 2.5 GHz ferrites sounded marginally better on Blu Dave. Head-Fi, Nov 2017
• 2017-11-29Watts explains that 2 GHz ferrites improve depth by blocking signal-correlated ground bounce from FPGA logic transitions, while random RF causes noise floor modulation and brightness. Head-Fi, Nov 2017
• 2017-11-30Watts says using Dave and Hugo 2 changed his headphone preferences: bright ones sound brighter, warm ones warmer, and some reputed high-end headphones distort with bass. Head-Fi, Nov 2017
• 2017-12-02Watts says a ferrite does not change the cable's signal impedance; it raises common-mode ground impedance, improving GHz isolation into DAVE's ground plane without affecting bandwidth. Head-Fi, Dec 2017
• 2017-12-02Watts calls the reference voltage the key internal supply, explains 2Qute's upgraded regulation and RF filtering, his jitter-removing DPLL, and pulse array jitter tolerance (DAVE 128 to 128.5 dB). Head-Fi, Dec 2017
• 2017-12-03Watts says his ferrite tests were on Blu 2 to DAVE, USB ferrites made no difference, and the warmer, smoother-sounding ferrite with better depth is the more transparent choice. Head-Fi, Dec 2017
• 2017-12-05Watts says he once doubted distortion below minus 120 dB mattered, but while designing DAVE he pursued much lower distortion because reduced distortion had always sounded better. RMAF 12:58
• 2017-12-05Watts says DAVE prototypes stalled at minus 120 then minus 130 dB distortion, while he aimed to beat the dCS Vivaldi's minus 130, until one idea cut 20 dB. RMAF 13:41
• 2017-12-05Watts says the fix took DAVE's distortion below minus 150 dB, being the last mechanism he could think of, and the listening test showed a big change in sound quality. RMAF 14:31
• 2017-12-05Watts says he expected cutting eighth to tenth harmonic distortion from 130 to 160 dB to sound warmer, but DAVE sounded brighter and sharper with clearer small details. RMAF 14:59
• 2017-12-05Watts says that, playing Shaun the Sheep through the DAVE prototype, his son, unaware of any change, immediately noticed the improved clarity. RMAF 15:45
• 2017-12-05Watts says his son, a guitarist and not an audiophile, heard an unannounced code change, showing tiny differences matter, and sets a target of 144 dB or below per harmonic. RMAF 16:30
• 2017-12-05Watts says pulse array eliminated the fundamental linearity problem of his 1990s DSD256 DACs; a minus 120 dB signal now measures within a thousandth of a dB, Mojo to DAVE. RMAF 18:43
• 2017-12-05Watts says Hugo's slimmer noise shaper improved only depth, and with DAVE's ten-times-larger FPGA he raised the noise shaper from 200 to 220 dB and depth deepened. RMAF 21:37
• 2017-12-05Watts says depth kept improving with noise shapers at 240, 260, up to 330 to 350 dB, a 0.0000001 dB change at minus 120 dB, easily heard blind. RMAF 22:21
• 2017-12-05Watts says Hugo 2 goes from 126 to 126.5 dB and DAVE from 128.5 to 129 dB; Chord uses femto clocks without fuss, and better clocks are not worth it. RMAF 43:11
• 2017-12-05Watts says pulse array's lower noise avoids input stage overload and NFM, Hugo 2 and DAVE use an analog noise shaper amplifier, and audiophile design swung from measurement to listening. RMAF 46:31
• 2017-12-05Watts says he listens only after thorough measurement, and shows DAVE with noise floor modulation eliminated at 2.5 volts and harmonics below minus 150 and minus 155 dB. RMAF 48:25
• 2017-12-05Watts says every Verilog module must pass a minus 301 dB signal unchanged, about 60-bit accuracy he considers needed for depth, and DAVE's noise shaper shows minus 300.99 dB. RMAF 49:13
• 2017-12-05Watts says the 0.01 dB error is an FFT residual, and DAVE's noise at 100 kHz is minus 200 dB, whereas DSD's high out-of-band noise causes problems for analog electronics. RMAF 49:58
• 2017-12-05Watts shows a jitter test with no visible jitter, says Mojo nearly matches DAVE, and credits DAVE's low 19/20 kHz two-tone distortion to its second-order analog noise shaper amplifier. RMAF 50:44
• 2017-12-05Watts says Europe and Asia have no review problem, half a dozen reviewers bought DAVEs at a discount, and the only problem is mainline US magazines. RMAF 54:08
• 2017-12-05Watts says skeptics bought Chord and upgraded Mojo to Hugo 2 to DAVE, every DAVE buyer buys a Blu 2, and this first show presentation aims to explain his technology. RMAF 55:28
• 2017-12-09Watts names DAVE, over 2 and a half years of work, and the M scaler on Blu 2, having envisioned needing 1,000,000 taps in the 1980s, as his hardest designs. article, Dec 2017
• 2017-12-18Watts says sampling images cause transient timing errors and their out-of-band noise overloads analog stages causing noise floor modulation, which none of his DACs from Mojo to DAVE measurably show. Head-Fi, Dec 2017
• 2017-12-24Watts says he plans long term: he foresaw a million-tap M scaler ten years ago, designed 1M-tap filters five years ago, and built in features like Dave's DX outputs. Head-Fi, Dec 2017
• 2017-12-25Watts explains DSD's 1-bit problems: lower resolution, modulator instability causing noise floor modulation, and small-transient delays, versus his 5-bit 2048FS pulse array and DAVE's -301 dB noise shaper. Head-Fi, Dec 2017
• 2017-12-25Watts says DAVE reproduces DSD64 identically to its digital-domain performance, but DSD is innately flawed versus PCM, which DAVE handles much better. Head-Fi, Dec 2017
• 2018-01-02Watts says unused BNC inputs on DAVE are fine, as the SPDIF receiver output is fixed at zero when left floating. Head-Fi, Jan 2018
• 2018-01-03Watts says Hugo 1's DSD filter had audible aliasing at -150dB, the new one is better than -240dB, and this work informs Davina, which will make aliasing negligible. Head-Fi, Jan 2018
• 2018-01-10Watts says Qutest was designed mainly for speaker systems; it suits those who like an external headphone amp's coloration, but for transparency with headphones he recommends Hugo 2 or Dave. Head-Fi, Jan 2018
• 2018-01-10Watts says his power pulse array work aims to give single DAC-amplifier benefits at hundreds of Watts, instead of Dave's 2W, with no loss of transparency. Head-Fi, Jan 2018
• 2018-01-11Watts says Hugo 2 and Dave limit at 0.5A RMS, so Dave gives 2.1W and Hugo 2 1.05W into 8 ohms; the 50 mA limit is the balanced output only. Head-Fi, Jan 2018
• 2018-01-11Watts says Dave's DX output is a 705/768 kHz signal with volume data embedded, making Dave a DX pre-amp; Qutest accepts DX data but ignores the volume. Head-Fi, Jan 2018
• 2018-01-11Watts says only Dave has DX outputs. Head-Fi, Jan 2018
• 2018-01-11Watts explains Qutest feeds linear power amps, Hugo 2 suits 1W/8 ohms and Dave 2W, while planned DX amps are pulse array DACs delivering 20W to hundreds of Watts. Head-Fi, Jan 2018
• 2018-01-11Watts says airborne RF is unlikely to induce ground-plane currents in DAVE's thick aluminum chassis, and without ground current there is no pick-up by the analog electronics. Head-Fi, Jan 2018
• 2018-01-11Watts describes balancing warmth and transparency: DAVE sounded too dark until the 256FS WTA filter, cheaper products degrade evenly from BluDave, and Mojo was set warmer for cheaper headphones. Head-Fi, Jan 2018
• 2018-01-11Watts now attributes USB's slight brightness on DAVE to RF through ground loops and the isolators' 2 pF, not timing, since Hugo 2 USB sounds like optical. Head-Fi, Jan 2018
• 2018-01-12Watts says BluDave, his untuned reference, came from minimizing aberrations; going from 0.5M to 1M taps is audible, and Davina will show how far BluDave is from perfect. Head-Fi, Jan 2018
• 2018-01-12Watts says without the solid aluminum block, external RFI would create currents on DAVE's ground plane; the chassis screens it. needs context Head-Fi, Jan 2018
• 2018-01-12Watts says none of his current projects include a DAVE 2, and with DAVE's Xilinx FPGA family still current, a replacement is not on his horizon. Head-Fi, Jan 2018
• 2018-01-12Watts says a battery-powered laptop via USB matches optical; USB's slight brightness is RF pick-up, not better timing, and vanishes when the laptop is unplugged from mains. Head-Fi, Jan 2018
• 2018-01-13Watts says super caps would not help Dave, defends Hugo 2's output stage, and says Dave below +4 and Hugo 2 below white never clip with headphones. Head-Fi, Jan 2018
• 2018-01-14Watts says volume is implemented in Hugo 2 exactly as in Dave. Head-Fi, Jan 2018
• 2018-01-16Watts says Dave would be about 99.988% accurate, yet connecting an M scaler to Dave is audible within 3 seconds, so these tiny errors are extremely important. Head-Fi, Jan 2018
• 2018-01-19Watts says doubling pulse array elements halves correlated jitter error, cuts noise 3dB and improves THD and small-signal resolution; Davina uses 40 elements to reach 135dB dynamic range. Head-Fi, Jan 2018
• 2018-01-22Watts describes a planned transient-error measurement, fearing 164,000 versus 1M taps may measure small, and recounts how cutting Dave's harmonics from -130dB to -150dB was unexpectedly audible. Head-Fi, Jan 2018
• 2018-01-25Watts explains AES dual data mode, says Hugo 2 and Qutest auto-assign channels while DAVE needs manual connection, and says a Mojo with Nighthawks or Aeons beats far costlier systems. Head-Fi, Jan 2018
• 2018-01-30Watts lists ways amps add bass bloom (2nd harmonic, low damping, coupling-cap dielectric absorption), says Hugo 2 avoids all three, and advises EQ or better headphones instead. Head-Fi, Jan 2018
• 2018-01-31Watts says Hugo 2 is limited by its 8.2V battery voltage while DAVE is not, and that external amps are mostly not used for lack of power. Head-Fi, Jan 2018
• 2018-02-08Watts says DAVE is unbeatable for transparency and depth over Hugo 2, but Blu 2 plus Hugo 2 wins on timbre, rhythm, bass and instrument power. Head-Fi, Feb 2018
• 2018-02-17Watts shares Hugo 2 measurement slides from his CanJam NYC talk, explaining low output impedance, load-independent distortion, no measurable noise floor modulation or jitter, and APx555 methods. Head-Fi, Feb 2018
• 2018-02-17Watts says he meant DAVE's crossfeed to disable outside headphone mode but kept it available because people like it, so users must unset it for speakers. Head-Fi, Feb 2018
• 2018-02-19Watts explains his discrete single-ended DAC combines I-to-V, filtering and headphone drive in one amplifier with two resistors and two capacitors; DAVE's balanced outputs add an inverting amplifier. Head-Fi, Feb 2018
• 2018-02-22Watts says DAVE at -3 dB gives exactly 3 V RMS at 0 dBFS, Chord's historical reference level, while 0 dB matches Hugo at 4.24 V RMS. Head-Fi, Feb 2018
• 2018-02-23Watts says a 10 times better FPGA let Dave reach 164,000 taps, and every tap-length increase improved sound quality. MajorHiFi 11:13
• 2018-02-23Watts says going from Hugo to Dave took nine months of coding yet gave an important but not night-and-day change, so he thought 164,000 taps neared the limit. MajorHiFi 11:29
• 2018-02-23Watts says after Dave's modest gain he chose 512,000 taps for the Blu upgrade as easy to place and route; it took about three months and sounded completely different. MajorHiFi 15:26
• 2018-02-23Watts says putting this FPGA in Dave would inject signal-correlated noise from 528 DSP cores into the ground plane, peaking at the smallest signals and degrading depth perception. MajorHiFi 20:02
• 2018-02-23Watts says a separate, galvanically isolated M Scaler keeps that noise out of Dave, isolation took two prototypes, another M Scaler is in progress, and timing recovery reaches 16-bit accuracy. MajorHiFi 20:49
• 2018-02-23Watts says wood blocks are hard to reproduce, an initial dynamic hit followed by timbre, which he notices when Dave drives efficient loudspeakers directly, plus a huge soundstage. Head-Fi, Feb 2018
• 2018-02-27Watts says the FPGA draws 10 or 12A at 1V, a 12W peak; the M scaler draws about 15W from mains, well isolated and RF filtered, as on Blu 2 and Dave. Head-Fi, Feb 2018
• 2018-03-08Watts says a proper mains RF filter needs Y capacitors, giving more leakage but a warmer sound, and that DAVE is relatively immune to mains quality. Head-Fi, Mar 2018
• 2018-03-08Watts gives sinc-equivalent accuracy as 12.2 bits for Hugo 2, 13.9 bits for Dave and 16.6 bits for the M scaler, below which WTA coefficients diverge from the ideal sinc. Head-Fi, Mar 2018
• 2018-03-13Watts says Dave's superior transparency comes from many factors beyond its noise shaper, which dominate given Hugo 2 and Qutest's noise shapers, and both benefit enormously from an M scaler. Head-Fi, Mar 2018
• 2018-03-16Watts says at -3 dB the balanced output is 6 V RMS across plus and minus, clipping is 13.6 V RMS, and output impedance is 33 ohms. Head-Fi, Mar 2018
• 2018-03-17Watts says never upsample at the source into his DACs; cascading two DAVEs via DX helps slightly versus an M scaler's huge change; isolating FPGA noise was essential for DAVE. Head-Fi, Mar 2018
• 2018-03-17Watts describes DAVE's development: individual RF filtering of digital sections, care over ground-plane return currents and layout, two ground planes, and Chord's patience over time and prototypes. Head-Fi, Mar 2018
• 2018-03-17Watts says ideal reconstruction needs an infinite-tap sinc; DAVE's WTA matches ideal to 13.9 bits and the M scaler to 16.6 bits, an unexpectedly large audible step. Head-Fi, Mar 2018
• 2018-03-20Watts says complex USB gear adds RF brightness, optical is the benchmark, and gives WTA overload margin, M scaler latency (630 ms, video mode 104 mS) and 16.6-bit accuracy. Head-Fi, Mar 2018
• 2018-03-22Watts explains the 2.75dB WTA overload margin, delays audio in JRiver to keep 1M taps with video, describes visible noise floor modulation, and gives DAVE and Hugo 2 level limits. Head-Fi, Mar 2018
• 2018-03-26Watts says channel separation figures matter less than crosstalk distortion, which he tested on Hugo 2 as a check of PSU-induced distortion; DAVE's low PSU impedance avoids it. Head-Fi, Mar 2018
• 2018-03-29Watts says nothing in DAVE exceeds 75 deg C and Blu 2's die reaches only 60 deg C, as the die mounts to the thick aluminum chassis. Head-Fi, Mar 2018
• 2018-04-04Watts lists tap lengths: DAC64 (1999) 1,024, Hugo (2013) 26,000, DAVE (2015) 164,000, Blu MKII (2017) 1,015,808; each increase plus WTA algorithm improvements raised sound quality. article, Apr 2018
• 2018-04-04Watts says 90% of Hugo 2's technology came from DAVE through reusable Verilog modules that are simulated, verified and listened to, giving Hugo 2 identical digital internal performance. article, Apr 2018
• 2018-04-04Watts weighs DAVE, the M scaler (1M taps, a lifetime dream) and Mojo (musicality he has heard from no non-Chord DAC), picks Mojo, and says Hugo most changed his listening. article, Apr 2018
• 2018-04-04Watts says all headphones improve further up the chain to Blu Dave, but each headphone's strengths and weaknesses become more exposed, so favorites may change. Head-Fi, Apr 2018
• 2018-04-04Watts says since Hugo bad recordings became enjoyable, concluding the brain copes with noise, harmonic distortion and frequency response but not digital's unnatural distortions. Head-Fi, Apr 2018
• 2018-04-08Watts says his MSI laptop PSU is grounded with many ground loops; DAVE with a battery laptop sounds better, but only by careful AB listening. Head-Fi, Apr 2018
• 2018-04-12Watts says DAVE and Hugo 2 run identical optical receiver code and chip, and 192k optical is marginal but works on DAVE with a quality transmitter and cable. Head-Fi, Apr 2018
• 2018-04-14Watts says ADCs may not resolve cable differences; compression tests on poor tracks prove little, but MP3 or AAC 320 sound softer and warmer than redbook, obvious on BluDave. Head-Fi, Apr 2018
• 2018-04-20Watts says USB is best, AES/EBU is a joke standard, and external clocks either worsen sound or do nothing because DAVE's crucial clock sits beside the pulse array. Head-Fi, Apr 2018
• 2018-04-27Watts responds to a review calling Hugo 2 merciless, contrasts live drums with reproduction, states Davina's goals of depth and speed, and says all design is his. Head-Fi, Apr 2018
• 2018-04-29Watts says he uses stock mains cables, heard no difference adding 300 MHz ferrites on the mains input, and DAVE has extensive supply RF filtering and regulation. Head-Fi, Apr 2018
• 2018-04-30Watts says the SYS2722 cannot measure Dave (-118dB versus -128dB on an APx555), calls NFM a top-3 SQ indicator, and uses Verilog simulation to verify -350dB and -300.99dB performance. Head-Fi, Apr 2018
• 2018-05-07Watts says Hugo 2's DSD filter exceeds 200 dB at 88.2 kHz, used on Blu 2; he heard only brain break-in; the M scaler outputs 705.6 kHz PCM from DSD. Head-Fi, May 2018
• 2018-05-08Watts thinks DAVE treats 705/768 kHz input identically in DSD+ and PCM+ modes, and keeps his DAVEs in PCM+ with M scalers. Head-Fi, May 2018
• 2018-05-11Watts says TT2 measures like Hugo 2 in DAC mode, gives 18W balanced and 7W SE without degradation, describes its supercap PSU, and denies working on a Dave 2. Head-Fi, May 2018
• 2018-05-13Watts says to use standby via button or remote, and that TT2 filters native DSD with Hugo 2's over-200dB filter, so it needs no dedicated DSD mode like Dave's. Head-Fi, May 2018
• 2018-05-13Watts posts his Munich TT2 presentation: larger FPGA, a noise shaper 100 times better than Hugo 2's, supercap PSU, output stage from the power pulse array project, measurements. Head-Fi, May 2018
• 2018-05-16Watts says TT2's balanced negative output uses the same amplifier as its single-ended output, so the balanced output is low distortion and simple, unlike Dave's. Head-Fi, May 2018
• 2018-05-17Watts says servers sound brighter with an illusion of transparency, hallmarks of RF noise, mostly via RF-sensitive power amps; a laptop feeding only Dave's USB gives the lowest RF. Head-Fi, May 2018
• 2018-05-17Watts says with bit perfect USB data only RF noise can change the sound, by creating noise floor modulation that sounds brighter; jitter has no influence on his DACs. Head-Fi, May 2018
• 2018-05-21Watts says the tingle from touching unearthed gear is leakage current discharging through imperfectly isolated anodizing, and it is safe because Dave's PSU is a low-leakage medical grade supply. Head-Fi, May 2018
• 2018-05-22Watts says Dave's negative output uses an op-amp for power amps only, while TT2's uses its high-power discrete stage for speakers and headphones, and suggests XLR-terminated headphone cables. Head-Fi, May 2018
• 2018-05-22Watts says only anodized surfaces such as Dave's chassis tingle, and he gets it only in hotels without earthing, from the leakage of his whole mobile rig. Head-Fi, May 2018
• 2018-05-24Watts says volume-matched TT2 beats Hugo 2 in depth, detail and separation, he uses only SE outputs on his 88dB speakers, and 20 Hz distortion ignores load. Head-Fi, May 2018
• 2018-05-25Watts says TT2 addresses headphone power (external amps mostly add coloration) and DAVE driving efficient speakers directly; its 18 watts drives any headphones, and he drives speakers from headphone sockets. Darko Audio 50
• 2018-05-25Watts describes his power pulse array amplifiers in development (200 watts to a kilowatt, single global feedback) and says TT2 uses their output stage, delivering five amps into headphones. Darko Audio 2:10
• 2018-05-27Watts says Stereophile's AP cannot measure Dave because ADC noise floor modulation interferes; the APx555 uses a notched second ADC for residuals, showing Dave's noise floor near -180dB. Head-Fi, May 2018
• 2018-06-17Watts says BluDave cannot voltage clip at +6dB but can current limit into 8 ohms (4.1V RMS, 2.1W), making +5dB the danger zone; quiet recordings may explain the poster's level. Head-Fi, Jun 2018
• 2018-06-24Watts says TT2 weighs 2.7 kg and travels well, its supplied PSU was chosen after much testing, and a linear PSU would almost certainly sound worse. Head-Fi, Jun 2018
• 2018-06-27Watts says aliasing ruins music: Hugo's -130dB DSD decimation was audible, Hugo 2, TT2 and M scaler reach -220dB, MQA manages -40dB, and 768 kHz needs 24 bits. Head-Fi, Jun 2018
• 2018-07-01Watts says AAC, short filters, MQA, minimum phase, NOS and DSD sound soft and warm from transient timing uncertainty; turning off the incisive filter similarly sounds warmer. Head-Fi, Jul 2018
• 2018-07-04Watts says current ADCs have aliasing, NFM and small-signal nonlinearity, so Davina recordings may show big changes even on Mojo; he benchmarks Dave with headphones and TT2 on 803 D3s. Head-Fi, Jul 2018
• 2018-07-17Watts agrees the goal is reducing ground currents, which that filter cannot touch as ground is unfiltered; only ferrites reduce Blu 2 and Dave RF common-mode ground currents. Head-Fi, Jul 2018
• 2018-07-18Watts says extra shielding will not help; ferrites, like BNC galvanic isolation, raise the RF coupling impedance between Blu 2 and Dave grounds, with the worst problem around 2GHz. Head-Fi, Jul 2018
• 2018-07-21Watts lists QBD76 at 18,000 taps, Hugo 1 at 26,000 and Dave at 164,000, saying each increase improved timbre, bass pitch and left-right soundstage. c w 15:36
• 2018-07-21Watts explains FPGA timing closure and placement, saying Dave began at 200,000 taps, failed to place and route, and finally worked at 164,000 (spoken as 'pounds'). c w 20:10
• 2018-07-21Watts says Dave's filter took nine months and was only modestly better than Hugo's; half a million taps on the new FPGA sounded hugely, unexpectedly better than Dave. c w 21:02
• 2018-07-21Watts says he uses mains in business class and carries the M Scaler because Hugo 2 and Dave are hard to hear without it; customs has not objected yet. c w 26:18
• 2018-07-21Watts says Dave owners have the Blu 2, or could use Davina, the AD converter, which will have an M scaler built in. c w 31:16
• 2018-07-22Watts says it is absolutely fine with Dave, its benefit over Blu2 being no need for ferrites on the BNC cables, which were only the top layer of icing. Head-Fi, Jul 2018
• 2018-07-26Watts says Qutest, Hugo 2, TT2 and Dave share the post-scaler process (WTA2 to 256FS, third-order filter to 104 MHz), notes diminishing returns, and previews DX amps' transparency. Head-Fi, Jul 2018
• 2018-07-27Watts explains dual-data and DX modes, M scaler DSD-to-PCM conversion with Hugo 2's 220 dB filter, says algorithm beats tap length, and compares R2R and delta-sigma timing errors. Head-Fi, Jul 2018
• 2018-08-04Watts explains TT2's 98,304-tap 16FS WTA1, says WTA2 matches Hugo 2 and Dave, TT2 sounds warmer than Hugo 2, and describes fixing 192kHz crackles in Windows. Head-Fi, Aug 2018
• 2018-08-06Watts says the M Scaler is fundamentally 3 bits more accurate than the TT or DAVE, guaranteed to recover the original analog signal to better than 16 bits. Pursuit Perfect System 4:13
• 2018-08-06Watts says it is more complicated: instrument separation, timbre variation and sense of flow come only with the scaled option, while DAVE gives transparency, detail, resolution and depth. Pursuit Perfect System 4:43
• 2018-08-06Watts says users must choose: for timbre, pitch, separation and focus, the option garbled in the transcript as 'OTAL'; for pure transparency and detail resolution, DAVE. needs context Pursuit Perfect System 5:13
• 2018-08-07Watts says he carries a TT2 and programming tool while Chord is still testing it, and will return to traveling with a Dave and Hugo M scaler. Head-Fi, Aug 2018
• 2018-08-13Watts advises 75 ohm BNC cables matching the M scaler's output; scaled DACs still differ: Dave beats Qutest, with a 20-element pulse array and 30 times lower distortion. Head-Fi, Aug 2018
• 2018-08-13Watts says the M scaler's Hugo 2 DSD filter beats Dave's DSD+, but DSD's amplitude-related timing errors and small-signal losses cannot be recovered; Davina should surpass PCM and DSD. Head-Fi, Aug 2018
• 2018-08-13Watts says he keeps it in PCM+ mode with an M scaler attached. needs context Head-Fi, Aug 2018
• 2018-08-14Watts says the first DX amp will have headphone outputs, Dave easily drives LCD-4 to 120 dB SPL with the best transparency, and suggests a TT2/Dave dealer demo. Head-Fi, Aug 2018
• 2018-08-17Watts says Dave will be more transparent than the first DX amp on headphones, and explains naming it 'power pulse array DAC' because 'digital amp' implies Class D. Head-Fi, Aug 2018
• 2018-08-20Watts speculates why the test filter is poor, and says the 16FS, WTA2 256FS and 2048FS path is identical from Qutest to Dave; noise shaper, pulse array and analog differ. Head-Fi, Aug 2018
• 2018-08-23Watts confirms DAC mode makes no difference to the signal path; it only sets the volume to -3dB and disables volume changes. Head-Fi, Aug 2018
• 2018-08-27Watts explains he avoids voltage mode DACs because output voltage modulates switching delays, giving about 0.03% THD and HF noise; his single stage combines I to V and drive. Head-Fi, Aug 2018
• 2018-08-28Watts explains he uses no coupling caps but a digital DC servo trimming the noise shaper, which takes 16 seconds to stabilize, hence the rainbow start-up and Dave's turn-on delay. Head-Fi, Aug 2018
• 2018-09-14Watts says linear PSUs lack RF filtering and sound brighter, Qutest benefits hugely from the M scaler but an M-scaled Dave easily beats an M-scaled Qutest. Head-Fi, Sep 2018
• 2018-09-18Watts says the M scaler PSU came from TT2 testing, grounded C13 PSUs caused ground loops, quality SMPS beat linears, the Chord driver works, and auto low-power mode exists. Head-Fi, Sep 2018
• 2018-09-26Watts says he designed IIR and FIR Davina decimation filters with over 250 dB rejection to test bandlimiting; he expects pre-ringing at 22.05 kHz to prove a red herring. Head-Fi, Sep 2018
• 2018-10-22Watts says studios now use Dave but need Davina, which is still a long way off, joking about his delays. Head-Fi, Oct 2018
• 2018-10-27Watts says TT2 drives his 802 D3 from the SE output, lists upcoming events, and says Dave remains well ahead of TT2 in depth and detail resolution. Head-Fi, Oct 2018
• 2018-10-27Watts says 10 versus 20 pulse array elements helps Dave's transparency, and his noise-shaped volume control is not bit perfect but passes a -301 dB test. Head-Fi, Oct 2018
• 2018-10-27Watts says the Hugo M Scaler is not sensitive to RFI, and that Dave is more transparent while M Scaler with TT2 is better for timbre, flow and separation. Head-Fi, Oct 2018
• 2018-10-30Watts says a black M scaler light means the source sends digital silence, calls a headphone amp after TT2 insane, and says the new DSD filter has aliasing below -250 dB. Head-Fi, Oct 2018
• 2018-11-07Watts says Hugo 2's DSD filter is his best, better than DAVE's DSD+ mode and any DSD-to-PCM utility, running at 705.6 kHz with more than 220dB filtering. Head-Fi, Nov 2018
• 2018-11-07Duplicate post: Watts says Hugo 2's DSD filter is his best, better than DAVE's DSD+ mode, running at 705.6 kHz with more than 220dB filtering. Head-Fi, Nov 2018
• 2018-11-18Watts lists three causes of DAVE dropouts with the M scaler: the source, DAVE's dual-data detector, and SPDIF losing lock; try BNC 3 and 4, else service. Head-Fi, Nov 2018
• 2018-11-22Watts suggests setting DAVE to PCM+ mode with the M scaler. needs context Head-Fi, Nov 2018
• 2018-11-30Watts says the dual BNC outputs are isolated from the other outputs, so noise from other DACs should not upset DAVE, and the optical output is fully isolated. Head-Fi, Nov 2018
• 2018-12-08Watts says DAVE took two and a half full-time years, he did everything he wanted, and he has not worked out how to fundamentally beat it. Head-Fi, Dec 2018
• 2018-12-09Watts says vinyl sounds soft and distorted to him; M scaler with DAVE beats vinyl on his objective criteria and emotional involvement, citing Pink Floyd Relics and Yes albums. Head-Fi, Dec 2018
• 2018-12-09Watts says he rarely has airport security problems with DAVE, the M scaler or Mojo, carried on or checked, recounting questions in Indonesia and over Hugo 2 in Hanoi. Head-Fi, Dec 2018
• 2018-12-12Watts shows DAVE's noise floor at minus 179 dB with or without signal, zero measurable though not zero NFM; a good conventional DAC goes from minus 160 to 140 dB. Pursuit Perfect System 18:40
• 2018-12-12Watts begins the story of how he arrived at a number for small-signal accuracy while developing DAVE, starting with designing Hugo One, the product that put Chord on the map. Pursuit Perfect System 19:47
• 2018-12-12Watts says both noise shapers were 200 dB yet differed; he finished Hugo with crossfeed at 98% capacity, then on DAVE's ten times larger FPGA investigated why depth differed. Pursuit Perfect System 22:58
• 2018-12-12Watts says he hesitated to publish the numbers for fear of the Sound Science Brigade, but released them because everyone hearing DAVE comments on its deeper depth. Pursuit Perfect System 26:01
• 2018-12-12Watts says TT2 has 10 elements and a 12th-order noise shaper beyond 300 dB, better than Hugo 2 but short of DAVE, with one 7 watt amplifier, giving better depth. Pursuit Perfect System 35:36
• 2018-12-12Watts says it works with the M Scaler, calls the measurements state of the art (only DAVE beats them), and gives the jitter-test floor as minus 170 dB, not 178. Pursuit Perfect System 40:30
• 2018-12-12Watts says with a 20 hertz signal, higher-order harmonics vanish by 3 kHz on DAVE and his other DACs, at 12 W into 8 ohms balanced, unlike other power amplifiers. Pursuit Perfect System 42:02
• 2018-12-13Watts gives tap lengths of DAC64 (1,000), QBD76 (18,000), Hugo in 2013 (26,000) and DAVE (164,000), saying each increase improved bass definition and soundstage. Pursuit Perfect System 9:06
• 2018-12-13Watts says he cannot explain why going from DAVE's 164,000 taps to the M Scaler's 1 million opens the soundstage, suggesting its 1.3 second window matches concert-hall reverberation time. Pursuit Perfect System 20:30
• 2018-12-13Watts explains 2 GHz ground-plane noise crossing the BNC isolation's 5pF; clip-on ferrites help Blu 2 but degrade the Hugo M Scaler, solid-core help slightly, cables beyond 2m don't. Head-Fi, Dec 2018
• 2018-12-13Watts says listening tests with Hugo, Hugo 2 and DAVE found no difference between USB cables, and the M scaler should be even less sensitive. Head-Fi, Dec 2018
• 2018-12-15Watts says TT2's 98,304 taps switch off with an M Scaler, and TT2 was not engineered to sound warm but expected warmer than DAVE and more refined than Hugo 2. Head-Fi, Dec 2018
• 2018-12-16Watts explains why a DAC's reference supply needs zero noise and impedance, says chip DACs hide poor references, and describes TT2's DAVE-standard discrete reference and its warmer sound. Head-Fi, Dec 2018
• 2018-12-16Watts says TT2 keeps DAVE's -3 dB equals 3 V RMS convention, clipping at +7 dB; CD cannot clip at +6 dB, with M scaler +10 dB, Blu-ray +13 dB. Head-Fi, Dec 2018
• 2019-01-10Watts says TT2's volume settings match DAVE's, with 0 dB at 4.23 V RMS, so it cannot clip below +6 dB in high gain. needs context Head-Fi, Jan 2019
• 2019-01-20Watts says DAVE cannot switch out WTA2 since its timing errors add artificial softness, and other up-samplers lack taps or WTA-like algorithms and sound unnaturally soft. Head-Fi, Jan 2019
• 2019-01-27Watts says the M scaler makes CD equivalent to a 705 kHz recording to 16 bits; with native 705 input both it and DAVE's 164,000-tap WTA1 pass through. Head-Fi, Jan 2019
• 2019-02-09Watts prefers the M scaler's DSD filter, which decimates to 16FS with better than -220 dB above 88.2 kHz, to DAVE's DSD+, concluding aliasing causes decimation's sound problems. Head-Fi, Feb 2019
• 2019-02-26Watts gives DAVE's BNC channel mapping for the M scaler, says the DX output is for future products, and warns 705 to 768 kHz conversion adds distortion and noise. Head-Fi, Feb 2019
• 2019-02-27Watts says all his galvanically isolated designs power the USB decoder from VBUS, isolating it so the DAC sees only I2S data without decoding noise. Head-Fi, Feb 2019
• 2019-03-27Watts says M scaled DAVE beats M scaled TT2 in every regard, a larger gap than he expected; the earlier comment compared M scaler plus TT2 with DAVE alone. Head-Fi, Mar 2019
• 2019-03-28Watts says he is not unhappy with TT2, drives his B&W 802s from it, and was surprised DAVE's lead was so large, from factors other than noise shaping. Head-Fi, Mar 2019
• 2019-03-28Watts says electronic design is his alone, cost limited TT2 with a higher than expected BOM, he hit the price-performance sweet spot, and demand exceeds Chord's expectations. Head-Fi, Mar 2019
• 2019-04-03Watts describes a nonlinear balance between transparency and refinement, recalls DAVE being too warm during development, and links soundstage width to depth and small-signal accuracy. Head-Fi, Apr 2019
• 2019-04-08Watts says Toslink is the reference input since it injects no RF into the ground plane, his DPLL removes source jitter, and he heard no consistent USB-optical difference. Head-Fi, Apr 2019
• 2019-04-11Watts compares his FIR and IIR Davina decimation filters on a square wave, explains phase linearity, says both reach 250 dB rejection, and expects FIR to sound better. Head-Fi, Apr 2019
• 2019-04-19Watts says Dave cannot clip below +3 dB on the volume control, or +6dB with the M scaler attached. Head-Fi, Apr 2019
• 2019-04-21Watts says DAVE is connected to mains earth, ground boxes have the whiff of snake oil, and buyers should do careful AB tests before buying. Head-Fi, Apr 2019
• 2019-05-25Watts explains decimation and aliasing, says tiny aliasing is audible, and preferred Hugo 2's -220 dB DSD filter to Hugo 1's -130 dB and DAVE's DSD+. Head-Fi, May 2019
• 2019-06-01Watts says crossfeed improves depth on Dave, Hugo 2 and TT2, not Hugo, due to 350dB noise shaping; Dave took 2 to 3 years and later DACs reuse its code. Head-Fi, Jun 2019
• 2019-07-17Watts says a DX output is dual AES plus volume data, then argues listening judgements and measurements both need great care, saying only the APx555 measures noise floor modulation accurately. Head-Fi, Jul 2019
• 2019-07-21Watts quotes dCS headphone specs (1.4W into 33Ω, 33Ω minimum) as identical power to Dave, presumably balanced, and notes Dave's 8Ω minimum suggests more current. Head-Fi, Jul 2019
• 2019-07-21Watts says the available voltage drive is identical, just over 6v RMS, and the lower minimum impedance indicates Dave can deliver higher currents. needs context Head-Fi, Jul 2019
• 2019-09-09Watts says M scaler accuracy depends on input, far beyond 24 bits on sine waves, at least 16.7 bits on transients; DAVE 2 is unplanned and DAVE took 2.5 years. Head-Fi, Sep 2019
• 2019-10-18Watts says pass-through is not bit perfect; it carries the M scaler's 2.76 dB insertion loss, so DAVE direct must be turned down 3 dB for comparison. Head-Fi, Oct 2019
• 2019-11-05Watts says Dave's design has not changed, Chord tests Daves in dual BNC mode for drop-outs, a right-channel-only issue is strange, and he will raise it with Chord's production director. Head-Fi, Nov 2019
• 2019-11-17Watts confirms pulse array element counts are per channel. Head-Fi, Nov 2019
• 2019-11-27Watts says he uses solid-core ferrite cables at home but not when traveling with Hugo 2, TT2 or DAVE, and notes a battery-powered Hugo 2 avoids ground loops. Head-Fi, Nov 2019
• 2019-12-04Watts describes a show where Blu 2 Dave outperformed a costlier vinyl setup in spaciousness, separation and engagement, and says he does not get vinyl. Head-Fi, Dec 2019
• 2019-12-06Watts says TID and SID are non-issues with digital sources, and explains the analog noise shaper amp eliminates crossover distortion, citing TT2 and DAVE plots and gain bandwidth figures. Head-Fi, Dec 2019
• 2019-12-16Watts says the simpler Hugo noise shaper sounded better in depth and detail; DAVE's ten-times-larger FPGA let him test this, and a 220 dB noise shaper improved depth. Passion for Sound 12:52
• 2019-12-16Watts says after three months he reached a final 330 dB versus 350 dB noise shaper, still heard subtle depth changes, and concludes any depth error is audible. Passion for Sound 13:35
• 2020-01-02Watts says noise floor modulation tests need identical settings with only the level reduced, and his plots show no measured modulation in any product from Mojo to DAVE. Passion for Sound 10:05
• 2020-01-02Watts says at similar prices he would choose TT2 plus M Scaler over a bare DAVE for musicality, though many will prefer DAVE for its extraordinary transparency. Passion for Sound 24:16
• 2020-01-02Watts says DAVE is much more transparent than even an M Scaler-fed TT2, the choice is personal, Qutest with another amplifier loses transparency, and many Qutest owners add M Scalers. Passion for Sound 24:58
• 2020-01-04Watts says he cannot talk about future Chord products but that DAVE 2 is not on his horizon. Head-Fi, Jan 2020
• 2020-01-06Watts says TT2 got huge headphone power after complaints about Hugo 2, helping drive speakers, that DAVE and Hugo 2 drive almost any headphone, and no DSP is fully transparent. Head-Fi, Jan 2020
• 2020-01-11Watts says USB only controls his APx555, advises staying at DSD64 rather than re-modulating to higher rates before M scaler and DAVE, and praises the M scaler's DSD filter. Head-Fi, Jan 2020
• 2020-01-24Watts says M scaler/Dave can run at +9dB without clipping into loads above 16 ohms, and there is no news on the amps as he has been busy. Head-Fi, Jan 2020
• 2020-01-27Watts says dual-BNC 768k on Mojo was dropped in 2015 to save power and the manual corrected; Mojo takes 768k on USB, and the algorithm matters more than tap length. Head-Fi, Jan 2020
• 2020-02-25Watts says cable length matters with DAVE because it requires sync, while his other DACs use the AES3 dual data flag and need no exact sync. Head-Fi, Feb 2020
• 2020-03-27Watts says the M scaler gives a natural sense of flow and less fatigue because loud instruments no longer modulate transient timing, about 10 times more accurate than DAVE alone. Head-Fi, Mar 2020
• 2020-04-09Watts says mains conditioners neglect RF, a single-blind test tied a new HF filter's warmth to noise floor modulation, and DAVE is about 13-bit accurate, M scaler over 16. Head-Fi, Apr 2020
• 2020-04-26Watts says TT2 and other DACs auto-switch dual BNC channels by data flag, but with DAVE the M scaler's left BNC must go to the bottom BNC pair. Head-Fi, Apr 2020
• 2020-06-04Watts says TT2 matches Mojo and DAVE: -3dB is 3V RMS and four remote clicks down gives 1.89V RMS; with an M scaler set -4, as it attenuates 2.75 dB. Head-Fi, Jun 2020
• 2020-06-25Watts calls Mojo a mini DAVE anyone with a smartphone can afford, says a DAC wins if it makes you more emotional, and must make decoding easy for the brain. Part-Time Audiophile 8:26
• 2020-06-25Watts says Class B crossover distortion yields very audible high-order harmonics, but a Class AB stage can eliminate it, as his second-order amplification does on Hugo 2, TT2 and DAVE. Part-Time Audiophile 19:19
• 2020-06-25Watts says PWM delay varies with signal level, modulating transient timing; the brain perceives 4 microsecond interaural delays; DAVE's interpolation filters originally ran to 16FS (768 kHz). Part-Time Audiophile 22:42
• 2020-06-25Watts says DAVE used a three-stage filter from 768 kHz up to 104 MHz, and he experimented replacing part of it with a WTA filter outputting every 1.6 microseconds. Part-Time Audiophile 23:30
• 2020-06-25Watts says replacing the conventional IR type filter with a WTA filter running to 88 nanoseconds was immediately audible in the starting and stopping of notes, such as piano attacks. Part-Time Audiophile 24:23
• 2020-06-25Watts says odd order harmonics sound worse because the ear generates second harmonic the brain compensates for, then recalls DAVE's three or four prototypes aimed at maximum linearity. Part-Time Audiophile 32:35
• 2020-08-03Watts says his projects will keep him busy for at least 18 months, Dave 2 is not among them, and it is not on his horizon. Head-Fi, Aug 2020
• 2020-08-04Watts says long term yes, if the bi-quad DSP engine can be made transparent, as digital loudspeaker crossovers need one, and says Dave has withstood his own newer designs. Head-Fi, Aug 2020
• 2020-08-11Watts calls amps that short inputs reckless, and says his MSI laptop beat a server, which sounded bright with false transparency from RF-induced noise floor modulation. Head-Fi, Aug 2020
• 2020-08-11Watts advises waiting for Dave, then comparing a desktop PC with an ungrounded battery laptop; if they sound the same, the source need not be a concern. Head-Fi, Aug 2020
• 2020-08-15Watts says differing BNC lengths affect delay, not sound quality, and since Dave uses sync detection mismatches could cause drop-outs or failure of 705/768 kHz dual data operation. Head-Fi, Aug 2020
• 2020-08-22Watts confirms DAVE 2 is not on his horizon, says projects take at least 18 months and DAVE over 3 years, stresses honesty, and calls dCS's philosophy very different. Head-Fi, Aug 2020
• 2020-08-25Watts says John Franks came up with the name Dave, which Watts turned into an acronym, because they wanted something fun. Head-Fi, Aug 2020
• 2020-09-10Watts says plugging Dave straight into the wall is fine, mains-cable ferrites made no audible change, and he habitually puts DACs on a separate socket, untested on Dave. Head-Fi, Sep 2020
• 2020-09-15Watts says Dave's remote uses RC5 38 kHz codes except some codes, such as standby, which use a different code. Head-Fi, Sep 2020
• 2020-09-30Watts says his DACs use switching regulators, which sounded better than linear ones from Hugo onward, and that random RF noise, not fixed switching noise, causes noise floor modulation. Head-Fi, Sep 2020
• 2020-10-09Watts says Dave sales numbers are confidential but large in high-end terms, and sales are still increasing after over five years in production. Head-Fi, Oct 2020
• 2020-10-19Watts says a poster's USB versus optical difference on Dave fits RF raising noise floor modulation, though he heard only a tiny change, and says he has heard NFM below -180 dB. Head-Fi, Oct 2020
• 2020-10-29Watts says the M scaler and TT2 filter DSD, removing out-of-band noise with 220 dB attenuation and decimating to 705 kHz, which sounds better than DAVE's non-decimating DSD filters. Head-Fi, Oct 2020
• 2020-11-11Watts compares 1M-tap rectangular sinc, Kaiser and WTA filters by measurement and listening, explains how the WTA equation was tuned, and concludes algorithm matters more than tap length. Head-Fi, Nov 2020
• 2020-11-13Watts says 4 ohms is too much for Dave unless the volume is at -6 dB or below. Head-Fi, Nov 2020
• 2020-11-23Watts says TT2's balanced output into 4 ohms may thermally trip, restarting once cool, single-ended into 4 ohms won't trip, and Dave would have no problem with the Voxativ. Head-Fi, Nov 2020
• 2020-11-26Watts says he checked the schematics for Chord: TT1 does have galvanic isolation on the HD USB input, the same circuit as TT2 and DAVE. Head-Fi, Nov 2020
• 2021-02-01Watts says recording engineers press him for Davina, contrasts N-bit 104 MHz modulation with 1-bit DSD64, won't disclose plans, and names depth and attack as audio's key challenges. needs context Head-Fi, Feb 2021
• 2021-03-22Watts attributes differences between CD players into Dave over optical to mains RF noise and ground loops, and says bit-perfect source differences come from jitter, RF noise or signal-correlated noise. Head-Fi, Mar 2021
• 2021-03-26Watts says TT2's XLR outputs connect directly to high-current output stages, while Dave's go through 33 ohm resistors with a low-current negative leg, meant for amplifiers, not headphones. Head-Fi, Mar 2021
• 2021-03-29Watts compares dCS Bartok's quoted noise and headphone output (1.4W into 33 ohms) with TT2's 10W, and says fixed noise at -127dB is inaudible while signal-dependent noise matters. Head-Fi, Mar 2021
• 2021-04-01Watts says disconnecting the M scaler charger avoids the source-M scaler-Dave loop, CD players inject RF into mains, and changing Dave's PSU invalidates the warranty. Head-Fi, Apr 2021
• 2021-04-01Watts says his Dave output figures from 300 to 33 ohms are accurate, 16 ohms should be OK, and the 8 ohm figure comes from measurements. needs context Head-Fi, Apr 2021
• 2021-04-03Watts says supply ferrites are fine, any trace of noise floor modulation seems audible so he expects desktop two-box, and stock cables with a battery M scaler matched Wave Stream. Head-Fi, Apr 2021
• 2021-04-06Watts says volume colors mean the same voltage across DAVE, TT2, Hugo 2 and Mojo (blue is 1.0V RMS), and all desktop DACs have galvanically isolated USB. Head-Fi, Apr 2021
• 2021-04-16Watts sets crossfeed to maximum on headphones and to minimum on his office HMS and Dave speaker system, saying depth improves in both. Head-Fi, Apr 2021
• 2021-04-21Watts says Dave's XLR is pin 2 positive and pin 3 negative, so set Dave to negative phase if the power amp does not also invert. Head-Fi, Apr 2021
• 2021-04-26Watts says 2 ohms at 20k is fine but 0.5 ohms needs care; his travel headphones, closed Aeon 2, suit Dave, Hugo 2 or TT2 and beat Utopia. Head-Fi, Apr 2021
• 2021-04-30Watts says balanced XLR doubles the voltage into a power amp, a +6dB change, and Dave's XLR outputs are for pre or power amps only, not headphones. Head-Fi, Apr 2021
• 2021-06-04Watts says metal-to-metal interfaces attenuate small signals, his analog noise shaper gives TT2 20GHz and Dave 0.5THz gain bandwidth, and the pulse array creates no noise floor modulation. Head-Fi, Jun 2021
• 2021-07-22Watts says electronics are more reliable left on, standby keeps the clocks running for those worried about 12W draw, and he keeps TT2 and Dave on. Head-Fi, Jul 2021
• 2021-07-23Watts says no Dave displays had failed per Matt, he runs his at setting 4, he has never seen significant burn-in, and the display MTTF exceeds 50,000 hours. Head-Fi, Jul 2021
• 2021-07-24Watts says resolution means resolving small signals, not fixed noise (21.3 bits for Dave); Dave resolves -186dB; and 1M taps' 16.7-bit accuracy now looks insufficient for transients. Head-Fi, Jul 2021
• 2021-08-07Watts says the display flickering is due to lack of lock and Dave should go back to Chord for a check-up. Head-Fi, Aug 2021
• 2021-08-26Watts says Dave drives the Stealth with ease, reaching an ear damaging 125dB SPL at maximum volume. Head-Fi, Aug 2021
• 2021-08-29Watts recommends a 768kHz ADC, plans pulse array ADC tests, favors digital volume over analog, and says grounding via Dave shorts its isolation; ground elsewhere, battery-power, or use a resistor. Head-Fi, Aug 2021
• 2021-08-30Watts says PSU leakage current is mostly 100Hz and inaudible, Xilinx lead times are 55 weeks, and more FPGA space would mainly benefit WTA2 and filters up to 104MHz. Head-Fi, Aug 2021
• 2021-08-31Watts says Stereophile's poor Dave -90.31dB result did not reproduce on his APx555, calls the SYS2722 inadequate, and shows Dave with zero measurable noise floor modulation and jitter. Head-Fi, Aug 2021
• 2021-09-28Watts says Qutest shares Mojo's discrete output stage, pure Class A into 300 ohms or more; on Hugo 2, TT2 and DAVE a second-order analog noise shaper eliminates crossover distortion. Head-Fi, Sep 2021
• 2021-10-22Watts says supplied BNC cables are starters; 2GHz ferrites, Wave cables or battery power cure ground currents; Qutest uses Mojo's output stage; M Scaler was developed with TT2 and DAVE. Head-Fi, Oct 2021
• 2021-11-28Watts says DAVE gives 111dB SPL without clipping into this easy headphone, so an extra amplifier would only add coloration and reduce transparency. Head-Fi, Nov 2021
• 2021-12-01Watts says DAVE gives 98dB SPL maximum with the 1266 and 102dB with the Diana Phi, both easy to drive for current. Head-Fi, Dec 2021
• 2022-01-04Watts says Dave drives the Susvara to 92 dB SPL, voltage limited, and gives volume limits (+4 solo, +7 with M scaler); preferring an amp means preferring distortion. Head-Fi, Jan 2022
• 2022-01-04Watts says Dave drives the Stealth to an ear damaging 100dB SPL, some 8dB more than the Susvara. Head-Fi, Jan 2022
• 2022-01-31Watts says DSP also degrades small-signal accuracy, recalling that during DAVE's development around 2014 he thought 200 dB noise shapers were enough since no one hears -200 dB. Darko.Audio 21:22
• 2022-01-31Watts says depth improved at each noise shaper step, 220 dB, 240 dB, up to DAVE's 350 dB, even 330 to 350; noise shapers shrink his -301 dB test signal. Darko.Audio 22:09
• 2022-01-31Watts says two or three years ago he found amplitude-dependent phase shift is audible as suppressed depth, while investigating why 1 million taps beat DAVE's 164 thousand for depth. Darko.Audio 24:34
• 2022-01-31Watts says formula, coefficients and four settings match DAVE, Hugo 2 and Hugo one; only implementation differs, using biquads instead of Hugo 2's dedicated serial DSP core. Darko.Audio 48:10
• 2022-01-31Watts says pro users often find the products themselves; many mastering engineers use DAVE, and at shows they press him on when the A to D converter will be finished. Darko.Audio 49:19
• 2022-01-31Watts presents Mojo 2: coupling capacitor removed, new noise shaper, and a UHD DSP EQ he says passes -301dB amplitude, phase and NFM transparency tests that 64-bit DSP fails. Head-Fi, Jan 2022
• 2022-02-01Watts says it reproduces -301dB but its -320dB noise floor at 6kHz prevents proving 0.001dB accuracy; the 4-element noise shaper is 250dB versus DAVE's 350dB. Head-Fi, Feb 2022
• 2022-02-06Watts says he considered an M Scaler mode for DAVE/TT2, TT2's 7W beats DAVE plus power amp, NFM-free treble sounds natural, and he has not started a DAVE replacement. Head-Fi, Feb 2022
• 2022-02-08Watts says 14 years consulting for semiconductor firms taught right-first-time design; finished designs are frozen so a 2015 DAVE sounds like a 2022 one, and he avoids sales-driven upgrades. Head-Fi, Feb 2022
• 2022-02-09Watts declines to name consulting clients for confidentiality, repeats he has not started a DAVE replacement, and says likewise for Hugo 2, Qutest and TT2: no Hugo 3 next. Head-Fi, Feb 2022
• 2022-02-12Watts explains why his digital DC servo avoids analog servos' capacitor sound, says switching it off on DAVE changed nothing, and that Poly is not his project. Head-Fi, Feb 2022
• 2022-02-13Watts says battery power on the M Scaler removed his need for ferrited BNC cables, and Wave cables removed the need for batteries, both cutting GHz ground currents into DAVE. Head-Fi, Feb 2022
• 2022-02-14Watts says 64-bit floating-point EQ creates noise floor modulation and small-signal errors; Mojo 2 uses 104-bit noise-shaped fixed point; his DACs need no warm-up or break-in. Head-Fi, Feb 2022
• 2022-02-15Watts attributes HF errors to ADC noise shapers and decimation, keeps HF filter off on DAVE via M Scaler, prices the Choral M Scaler at DAVE level, and rejects XMOS. Head-Fi, Feb 2022
• 2022-03-05Watts says all his DACs are non-inverting, with DAVE offering a choice of positive or negative polarity. Head-Fi, Mar 2022
• 2022-03-16Watts describes recording an amateur orchestra with a Blumlein ribbon mic into a Focusrite ADC, compares playback with live, and blames lost depth, transients and timbre on the ADC. Head-Fi, Mar 2022
• 2022-03-19Watts says the ringing is expected, the 16-bit result is state of the art with only TT2 and DAVE slightly better, and Mojo sold in large numbers after 2015. MFG Audio Reviews 45:45
• 2022-03-22Watts says all represent his best at their price and time, sharing a common design thread, but Mojo (units reached, musicality) and DAVE stand out. article, Mar 2022
• 2022-03-22Watts lists his systems: Hugo M Scaler, TT2 and B&W 803 D3 at home; M Scaler, DAVE and DCA Stealth in the office; M Scaler, TT2 and Stealths for flying. article, Mar 2022
• 2022-03-27Watts recounts redesigning Qutest's regulation after Qute proved PSU sensitive, admits his 2016 USB preference on Dave was RF brightness, and calls optical the reference input. Head-Fi, Mar 2022
• 2022-03-28Watts details SPDIF word clock extraction and his frequency-locked DPLL on a 104.25MHz clock, and says USB can match optical but RF leaks through the 2pF isolation. Head-Fi, Mar 2022
• 2022-04-09Watts says -301 dB is about 600 electrons driving a Stealth, yet many listening tests, some blind, show it matters, as with Dave versus TT2's small difference. Head-Fi, Apr 2022
• 2022-04-12Watts says DAVE is earthed because its PSU is inside the chassis, TT2's double-insulated supply needs no earth, and earthing is moot since GHz noise is the main problem. Head-Fi, Apr 2022
• 2022-04-14Watts explains Verilog module simulation, says improving Dave's noise shapers from 200dB to 350 dB improved depth each step, and treats the -301 dB test as his transparency metric. Head-Fi, Apr 2022
• 2022-04-28Watts confirms DAC mode is identical to pre-amp mode fixed at -3dB, so pre-amp mode at -3dB gives identical performance. Head-Fi, Apr 2022
• 2022-05-03Watts says something gives a small improvement, judged with two DAVEs via the DX output, far less than an M scaler; he notes his independence and refers pricing to Chord. needs context Head-Fi, May 2022
• 2022-05-23Watts says DAVE's DX outputs carry 705/768 kHz from its 164,000-tap WTA1 filter and should sound better than Qutest's 48k taps; Qutest ignores the embedded volume data. Head-Fi, May 2022
• 2022-05-23Watts says the DX protocol's volume data is for future DAC power amps without volume controls, and DAVE between an M scaler and TT2 would just pass data through. Head-Fi, May 2022
• 2022-06-12Watts recounts crossfeed giving an out-of-head experience with a Hugo 2 prototype on a flight, never with the original Hugo, linking better small-signal accuracy to more effective crossfeed. Head-Fi, Jun 2022
• 2022-06-27Watts says pure DSD and R2R DACs are fundamentally limited, DAVE's noise shaper is not capped at 17th order, the HF filter sits after WTA2, and car batteries are ideal. Head-Fi, Jun 2022
• 2022-06-27Watts says TT2's crossfeed code is identical to DAVE's, but its benefits may be more apparent on DAVE because of DAVE's better depth and detail resolution. Head-Fi, Jun 2022
• 2022-06-28Watts says every Chord desktop DAC since DAVE has galvanic isolation with the USB decoder source-side, and battery-powered Mojo 2 or Hugo 2 with headphones won't need it. Head-Fi, Jun 2022
• 2022-06-29Watts explains a swollen 1000uF clock-regulator filter cap in a DAVE is very unlikely as a wear failure and suggests miswiring during a PSU change, which he does not recommend. Head-Fi, Jun 2022
• 2022-06-29Watts says DAVE targets a half life over 25 years; connectors and the display are likely failure points, so use standby or display message mode (disp 4). Head-Fi, Jun 2022
• 2022-07-01Watts says the new display needs a different protocol so the FPGA is updated, with no change to sound quality, and warns not to assume a linear PSU is better. Head-Fi, Jul 2022
• 2022-07-09Watts explains WTA1 filters to 16FS, WTA2 to 256FS, then a three-stage IIR filter to 104MHz feeding noise shapers and 20 pulse array elements, each stage with different requirements. Head-Fi, Jul 2022
• 2022-07-14Watts says the M Scaler is essential, PGGB sounded like an apodizing filter, and the M Scaler reconstructs transient timing beyond 16 bits, passing -301 dB via dual BNC. Head-Fi, Jul 2022
• 2022-07-18Watts calculates DAVE's PSU-induced errors at -198dB from the linear regulator and -234dB from the SMPS, saying RF noise is what changes sound with supplies, and SMPS has less. Head-Fi, Jul 2022
• 2022-07-19Watts says the amp is in the background, old recordings involve via M Scaler and DAVE, and his Blumlein test recordings showed ADC losses: less depth, softer transients, warmer balance. Head-Fi, Jul 2022
• 2022-07-25Watts recounts DAVE's nearly 3-year development, questions Stereophile's 16-bit measurements, cites -127dB A-weighted, calls SINAD worthless, and says filters must reconstruct transient timing. Head-Fi, Jul 2022
• 2022-08-19Watts says going from DAVE's 164,000 taps to the Hugo M Scaler's 1 million made a bigger difference than expected, opening the soundstage, and that 16-bit accuracy is not enough. AVstore 6:55
• 2022-08-19Watts says Chord's pulse array DACs, Mojo to DAVE, run a 104 MHz clock and reproduce 52 MHz; R2R mishandles 768 kHz; delta-sigma caps at 3 or 6 MHz. AVstore 27:43
• 2022-08-19Watts says the DAC's resolving power limits transient reconstruction, and DAVE, Hugo 2 and TT2 add WTA2 filtering to 256FS and another filter from 256FS to 2048FS. AVstore 28:30
• 2022-08-19Watts says DAVE measures slightly better with the M Scaler, with slightly lower distortion and noise and no jitter difference, because DAVE's WTA filter does no work and 80 percent of the chip sits idle. AVstore 39:21
• 2022-08-19Watts says DAVE with his prototype scaler and Dan Clark Audio Stealth headphones came close to his live recordings, but depth was one-third or 50 percent less. AVstore 46:35
• 2022-08-31Watts says TT2 had no cost-saving compromises, DAVE proved more transparent than he expected, Chord is engineer-run, and noise floors are about -400 dB (digital) and -350 dB (best noise shapers). Head-Fi, Aug 2022
• 2022-09-06Watts says measurements correlate weakly with listening and depend on intent, his published results represent production DAVEs, and buyers should listen at home before purchasing. Head-Fi, Sep 2022
• 2022-09-07Watts says unidentified blind tests kill sensitivity, DAVE has no measurable noise floor modulation, and explains setting up the AP test correctly with -999dB and fixed input levels. Head-Fi, Sep 2022
• 2022-09-14Watts recounts RF filters warming the sound since the 1980s, and says a null result with Mojo 2's flat UHD DSP HF filter shows the effect is noise floor modulation. Head-Fi, Sep 2022
• 2022-09-16Watts says vinyl's clicks and lack of transparency rule it out, his M scaled Hugo 2 and DAVE are far more involving, and his recording played back warmer than live. Head-Fi, Sep 2022
• 2022-09-18Watts says with DAVE and a prototype of the new scaler, left-right accuracy of his recordings is identical to perfect, but depth is not. The Source AV 18:19
• 2022-09-18Watts says the cello sounded about 2.5 meters away on DAVE, about 2 on Hugo 2, about two with M Scaler (as transcribed), half a foot on conventional DACs. The Source AV 19:00
• 2022-09-18Watts says headphones are much brighter than loudspeakers, yet his recording on Stealth, DAVE and the scaler sounds darker, warmer and softer than the very bright reality. The Source AV 19:40
• 2022-09-18Watts says Mojo was still popular, and DAVE, now 7 years old, sells as well as it did 5 years ago, which he did not expect. The Source AV 30:25
• 2022-09-18Watts says TT2, DAVE and Hugo 2 have a WTA filter from 16FS to 256FS, unlike the 1FS to 16FS WTA, improving speed and the starting and stopping of notes. The Source AV 39:35
• 2022-10-12Watts says DAVE is FPGA-based, that an FPGA lets him design his own digital hardware, and that the design process is much the same as for a silicon chip. Upscale Audio 1:13
• 2022-10-12Watts says another benefit is that conversion to analog is done with discrete components rather than on a chip. Upscale Audio 2:22
• 2022-10-12Watts says the discrete conversion components are fed from a different power supply and the digital components are completely isolated. Upscale Audio 2:30
• 2022-10-12Watts says noise floor modulation is controlled by isolating the digital and analog domains and by the conversion architecture, the pulse array inside DAVE. Upscale Audio 2:50
• 2022-10-12Watts says it creates harmonic and anharmonic distortion, calls the latter really nasty, and says only the WTA filter is designed to minimize these; the M Scaler adds computing power. Upscale Audio 3:50
• 2022-10-12Watts says that when a studio engineer listens to a DAVE, they hear the original performance. Upscale Audio 6:03
• 2022-10-12Watts says it runs from 44.1 to 768 kHz and has BNC, AES, optical and USB inputs. needs context Upscale Audio 6:27
• 2022-10-12Watts begins explaining that he and John Franks were trying to figure out the name. needs context Upscale Audio 7:32
• 2022-10-12Watts says that with the Hugo name already used they wanted something different, and John Franks suggested Dave, a fun name in the UK. Upscale Audio 8:07
• 2022-10-12Watts says his father and uncle were called Dave and he coined 'digital to analogue veritas in extremis', truth in extreme, reflecting DAVE's aim to close the gap to unamplified sound. Upscale Audio 8:37
• 2022-11-25Watts says Mojo 2 has the digital DC servo introduced with DAVE in 2015 plus DC protection on its relays, calls the reported fault unique, and wants the unit. Head-Fi, Nov 2022
• 2022-12-21Watts says the effect is barely measurable near the FFT noise floor and unheard by others, suggesting the Feliks amp picks up display multiplexing noise through grounding or RF. needs context Head-Fi, Dec 2022
• 2023-01-12Watts says he uses positive phase and sets the M scaler's HF filter off with DAVE, and that absolute phase differences are small and depend on recording and transducer. Head-Fi, Jan 2023
• 2023-01-16Watts turns DAVE's HF filter off with the M scaler, doubts a Hugo 2-priced portable scaler-DAC by 2032, sets crossfeed to max, and says more taps add depth. Head-Fi, Jan 2023
• 2023-02-04Watts says improving small-signal amplitude accuracy improved depth, and developing Dave with a bigger FPGA after Hugo let him try better noise shapers. Dusty Audio 20:50
• 2023-02-04Watts says he thought 200 dB good enough in 2015, but Dave allowed better noise shapers with 20 elements, which he tested by listening. Dusty Audio 22:26
• 2023-02-04Watts says a 220 dB noise shaper audibly improved depth over 200 dB, so over three months of Dave development he kept improving it until the sound stopped improving. Dusty Audio 23:10
• 2023-02-04Watts describes raising Dave's noise shaper through 240, 260, 280, 300 and 330 dB with daily coding, simulation and listening tests, eventually reaching 350 dB. Dusty Audio 23:57
• 2023-02-04Watts says going from 330 to 350 dB was the first step where depth differences became hard to hear, and that small-signal accuracy is vital to depth and detail. Dusty Audio 24:38
• 2023-02-04Watts says Chord DACs from Mojo 2 to Dave have no measurable noise floor modulation, all others do, and that any amount, however small, is subjectively important. Dusty Audio 33:58
• 2023-02-04Watts says another Dave can connect to the DX outputs; testing two Daves, it sounded better as the second did no WTA processing, but he avoided promoting buying two. Dusty Audio 1:02:44
• 2023-02-04Watts says updates were impossible in 2015, now technically possible; FPGA code is optimized to the hardware, and Dave took two and a half to 3 years before he moved on. Dusty Audio 1:03:33
• 2023-02-04Watts says with his MSI laptop into the M Scaler and Dave, optical and USB sounded the same so he used USB, before his son built him a high-performance computer. Dusty Audio 1:07:10
• 2023-02-05Watts says Japanese reviewers played their own music at a Tokyo show on 803s, a pre-Ultima Chord amplifier, DAVE and an M Scaler; show demos normally sound worse. Soundnews 7:06
• 2023-02-05Watts says another signal path and electronics always degrade transparency, so he makes the DAC powerful enough for any headphone; DAVE handles 99% of headphones. Soundnews 12:37
• 2023-02-05Watts says TT2 was made more powerful so no separate headphone amp is needed; in analog simpler is better, as each solder joint, contact and amplifier audibly degrades sound. Soundnews 13:10
• 2023-02-05Watts says DAVE was developed with its switching supply, showing no noise floor modulation or 100 Hz issues and with extensive internal RF filtering; TT2 got more supply work. Soundnews 36:34
• 2023-02-05Watts says DAVE is different: he has not done battery tests on it, as its supply is more complicated, plus and minus 15 volts and 5 volts. Soundnews 43:18
• 2023-02-05Watts says isolated BNC is not quite as good as optical; non-isolated BNC is much worse; USB follows, isolated on TT2 and DAVE; optical is the primary reference input. Soundnews 49:45
• 2023-02-05Watts says DAVE was two and a half years in development and launched around 2015. Soundnews 52:07
• 2023-02-05Watts criticizes firmware updates that keep changing the sound; when DAVE launched he argued with John Franks, saying it needed replacing in 3 years, while Franks wanted at least 5. Soundnews 53:19
• 2023-02-05Watts says DAVE, in its seventh or eighth year, is still the best DAC available, and he is working on a much more expensive reference DAC of unknown price. Soundnews 54:15
• 2023-02-05Watts says DAVE was constrained by size but aimed at a sound quality and technical performance target regardless of cost. Soundnews 55:00
• 2023-02-26Watts says a cold-start test found no significant change, so Hugo 2's 10-minute warm-up on planes is more about his ears and headphones adjusting to cabin pressure. Head-Fi, Feb 2023
• 2023-02-26Watts says more voltage comes from amp gain, more elements raise I/V current if the PSU and output stage allow, and Stealth gets ample volume from DAVE or Hugo 2. Head-Fi, Feb 2023
• 2023-03-01Watts says direct-cut discs are rare and vinyl reproduces tape or digital, and DAVE's greater resolution over TT2 is not due to its 3dB gain difference. Head-Fi, Mar 2023
• 2023-03-01Watts says 2pF across the M Scaler's USB and BNC isolation gives about 80 ohms at 2 GHz, letting current reach DAVE's ground plane; optical may beat USB, source depending. Head-Fi, Mar 2023
• 2023-03-16Watts says DAVE's DSD+ mode filters without decimating, yet the Hugo M Scaler's DSD conversion sounds better because its filtering is more effective, and explains decimation. Head-Fi, Mar 2023
• 2023-03-18Watts says TT2 has higher distortion than Dave, that third-party Dave measurements fall far short of his own, and quotes Hi-Fi News measuring 0.000007% THD at 1kHz. Head-Fi, Mar 2023
• 2023-03-19Watts shares a 16-bit -90.3dB undithered test of the returned Stereophile Dave, points to PWM DAC slides, and says measurements show how bad, not how good, something sounds. Head-Fi, Mar 2023
• 2023-03-19Watts says phase shift with amplitude, found after the M scaler work, affects depth; tuning Mojo's noise shaper for minimal -301dB phase error led to Mojo 2's UHD DSP. Head-Fi, Mar 2023
• 2023-03-23Watts says he bought B&W 803 D3s after a Japan show demo with M scaled Dave, and that open-back panel speakers need big rooms for depth. Head-Fi, Mar 2023
• 2023-03-26Watts says the limit is reached when doubling taps is inaudible; during Covid he investigated it while working on a scaler to match DAVE, stressing reconstruction accuracy over taps. Eric's Hi-Fi 3:09
• 2023-03-26Watts says he has not started work on the DAVE replacement yet. Eric's Hi-Fi 8:36
• 2023-03-26Watts says his focus is the new scaler and the Ultima DAC; other projects wait until the Ultima DAC is finished, and DAVE replacement work has not started. Eric's Hi-Fi 8:40
• 2023-03-26Watts says he prefers solving problems fundamentally to selling costly supplies; DAVE predates his power supply work but has more RF filtering than TT2, and he is satisfied with it. Eric's Hi-Fi 20:03
• 2023-03-26Watts says M Scaler jitter is nanoseconds, so that criticism is irrelevant; DAVE measured extraordinarily for him and HiFi News, recalled as 0.0000 four or five zero seven percent distortion. Eric's Hi-Fi 25:05
• 2023-03-26Watts says DAVE measures better than any DAC he has seen, yet others using an APx555 differ; one manufacturer's terrible TT2 and M Scaler results came from ground loops. Eric's Hi-Fi 25:47
• 2023-03-28Watts says errors of a thousandth of a dB in amplitude or a thousandth of a degree in phase are audible, and recalls DAVE's development starting from 200 dB noise shapers. The Headphone Show 43:19
• 2023-03-28Watts says DAVE's noise shapers going from 200 to 220 dB, and later 330 to 350 dB, improved depth; fixed noise is fine but signal-dependent noise creates noise floor modulation. The Headphone Show 44:02
• 2023-03-30Watts gives Stealth SPL at 0dBFS (98.3 dB Hugo/Mojo, 100.0 Dave, 103.4 TT2 headphone, 109.1 balanced), warns against long listening above 80dB, and suggests volume settings. Head-Fi, Mar 2023
• 2023-04-03Watts says what is coming up is a new scaler to match DAVE. Amplify Audio 41
• 2023-04-03Watts says DAVE's transparency and depth come from small-signal accuracy, and that before DAVE he assumed noise shapers needed only 200 dB (32-bit) performance. Amplify Audio 4:53
• 2023-04-03Watts says on DAVE he heard depth improve from 200 to 220 dB noise shapers and up to 350 dB, leading to his rule that modules reproduce -301 dB perfectly. Amplify Audio 5:34
• 2023-05-20Watts says improving DAVE prototype harmonics from -120 dB to below -150 dB sounded brighter and more transparent; white volume cannot clip but deeper can, at ear-damaging levels. Head-Fi, May 2023
• 2023-06-18Watts says mains conditioners do little for RF, an external headphone amp only degrades transparency except perhaps with Susvara (92dB SPL max from Dave), and warns about 80dB. Head-Fi, Jun 2023
• 2023-06-19Watts says an unnamed project started in 2018 with a first PCB in Feb 2019, his longest; he flies with a Bixpower, Hugo 2, Hugo M Scaler and DCA Stealth. needs context Head-Fi, Jun 2023
• 2023-08-30Watts says DAVE has RF filters on its outputs and a pre-amp adds random RF noise and noise floor modulation, so the most transparent pre-amp is none. Head-Fi, Aug 2023
• 2023-09-29Watts reports from SoCal CanJam and a visit to Atlantic Studios West, which bought Dave and Mojo 2s, where recording engineers were interviewed about Chord gear. Head-Fi, Sep 2023
• 2023-10-01Watts says Tom interviewed Atlantic Studios' four recording engineers, who bought DAVEs and Mojo 2s about a year ago, and he joined after arriving early for jet lag. The Source AV 17:19
• 2023-10-01Watts says they also use Mojo 2 in the main studios when they do not have access to DAVE. The Source AV 20:43
• 2023-10-01Watts says that as he improved products such as Hugo, Mojo 2, Hugo 2 and DAVE, headphones started to sound different. The Source AV 21:37
• 2023-10-01Watts says better DACs make headphone faults easier to hear, and some people plug a headphone into DAVE, find it sounds wrong, and blame DAVE. The Source AV 21:49
• 2023-10-01Watts says DAVE cannot fix a headphone's problems, so try another; asked by an Atlantic engineer about 'magic fairy dust', he said he had been grinding it out 40 years. The Source AV 22:11
• 2023-11-29Watts says the DAVE update fixed occasional dropouts with the M Scaler in about 1% of units by improving SPDIF error tolerance, with no sound change. Head-Fi, Nov 2023
• 2023-12-04Watts says Stereophile's Dave response curves are wrong, likely ignoring latency, and that its 384k response reflects the filters from 16FS to 104M and analog filtering. Head-Fi, Dec 2023
• 2023-12-05Watts says at 384k Dave's WTA1 is flat to 191.8kHz, with response limited by analog and other digital filters. Head-Fi, Dec 2023
• 2024-01-19Watts says early DAVE prototypes had slightly worse harmonic distortion than the dCS Vivaldi, which he improved on, but his only sound target is live unamplified music. Head-Fi, Jan 2024
• 2024-03-20Watts begins recounting his work developing DAVE. MFG Audio Reviews 43:09
• 2024-03-20Watts says he measures designs digitally down to -400 dB by FFT and listens as errors are removed; while developing DAVE his noise shapers performed at 200 dB. MFG Audio Reviews 43:16
• 2024-03-20Watts says listening tests must decide whether something is better, and that DAVE gave him a brand new FPGA with plenty of capacity. MFG Audio Reviews 44:51
• 2024-03-20Watts says moving to a 220 dB noise shaper changed only depth, with distant instruments sounding more distant on his depth test tracks, and he kept improving until 350 dB. MFG Audio Reviews 45:02
• 2024-03-20Watts says even 330 to 350 dB was audible in blind tests, so tiny signals' amplitude and phase must be perfect or depth changes; analog components show similar errors. MFG Audio Reviews 45:45
• 2024-03-20Watts says a battery in DAVE is a good idea, mentions someone feeding a 120-volt battery into DAVE's mains input with good results, and would design DAVE differently today. MFG Audio Reviews 56:32
• 2024-04-17Watts says pre-production Quartet into Dave beat an M scaled Dave, it works with all current DACs, and a dedicated bit clock would only add RF. Head-Fi, Apr 2024
• 2024-05-04Watts says Quartet replacing a Hugo M Scaler on another listener's Dave made instruments sound real, and describes ADC decimation filter work and the 104MHz pulse array ADC. Head-Fi, May 2024
• 2024-05-10Watts says the sweet point is 16FS and that DAVE takes up 16FS. Reactcore 1:00
• 2024-05-10Watts says no competition has pressured him to replace Dave; others make rich warm or bright analytical DACs, while he wants a transparent DAC that recovers the original mic feed. Reactcore 10
• 2024-05-16Watts says 200-plus-component RF filters at Quartet's input and supply output keep RF out of Quartet and DAVE; stopping circulating currents makes BNC cable quality irrelevant. ConvinceMeAudio 2:12
• 2024-05-16Watts says optical would require changing the DAC and fails anyway with DAVE and scaler both on mains, so he kept dual BNC and contained the noise inside the product. ConvinceMeAudio 10:19
• 2024-05-16Watts agrees; the price is not set because the design is not quite finished, but it will cost more than DAVE. ConvinceMeAudio 12:03
• 2024-05-28Watts reports strong press and user reactions to Quartet with DAVE in Munich, says rivals have not closed DAVE's technical lead, and that Quartet lifts DAVE further. Head-Fi, May 2024
• 2024-05-29Watts shows a pre-production Quartet M Scaler prototype designed to match DAVE: 6 years of development, two million lines of code, 75 amp supply, five 200T FPGAs. HIFICLUBE.NET JVH 8
• 2024-06-18Watts says Quartet will cost more than DAVE, and describes Spice-modeled 'pinch-off' RF filters in its separate supply and input, isolating DAVE from its noise and making the sound warmer and smoother. article, Jun 2024
• 2024-07-01Watts lists DAVE's three DSD options with a Hugo M Scaler; the scaler's DSD filter (better than 200dB rejection) sounds best, and he studies decimation limits via the ADC project. Head-Fi, Jul 2024
• 2024-07-12Watts says he has not started a DAVE replacement; a DAVE owner who sold his unit heard Quartet with DAVE at Munich and decided to buy DAVE again. HIFICLUB 50:50
• 2024-07-12Watts says years of small improvements made progress hard to judge; plugging Quartet into his friend's system with M Scaler and DAVE made a huge difference, like forgetting the hi-fi. HIFICLUB 52:22
• 2024-07-12Watts says it was one of five such experiences in his life; the friend, who owns DAVE, TT2 and two M Scalers, expected better but not this much better. HIFICLUB 53:11
• 2024-07-12Watts says Quartet elevates DAVE to a new level, citing an ex-DAVE owner who now has to buy DAVE again. HIFICLUB 53:56
• 2024-07-25Watts says he has worked on Quartet at least 6 years, since the Hugo M Scaler was finished, made discoveries over COVID; it matches DAVE, price undecided. Hifi Pig TV 34
• 2024-07-25Watts says he has never had security issues carrying an 'MSC' (probably M Scaler) or DAVE, or the Quartet to Munich as carry-on; Mojo 2 once caused an issue. Hifi Pig TV 3:43
• 2024-09-29Watts says the friend keeps a separate apartment for hi-fi, with a main system and a mini system, and that he plugged Quartet into the friend's DAVE. The Source AV 13:49
• 2024-09-29Watts says Quartet reconstructs transient timing more accurately, aiding timbre and instrument separation; digital mis-times transients, only the M Scaler approach recovers them, and it put DAVE in a new game. The Source AV 15:46
• 2024-09-29Watts says Quartet works well with DAVE, but warns about using DAVE with a Class D power amplifier. The Source AV 16:28
• 2024-09-29Watts says it will be more expensive than DAVE, hopefully not by too much, which he knows from his rough idea of the bill of materials cost. needs context The Source AV 18:58
• 2024-10-05Watts says TT2's single-ended output drives his B&W 803 D3 speakers directly with its 7W output, which DAVE cannot do, with enough volume even for movies. Head-Fi, Oct 2024
• 2025-01-09Watts describes a transient reconstruction test giving the M Scaler 22-bit accuracy but says raw numbers miss perception, and rejects an extra amp since DAVE drives Stealth to ear-damaging levels. Head-Fi, Jan 2025
• 2025-01-13Watts compares feed-forward correction (about 20dB) with his second-order analog noise shaper (90dB), showing TT2 into 8 ohms, and links crossover distortion to amplitude-dependent transient delay. Head-Fi, Jan 2025
• 2025-02-18Watts says the HF filter fails a null test but not perceptually, citing a decimation-filter test showing its sound change comes from less out-of-band noise and noise floor modulation. Head-Fi, Feb 2025
• 2025-05-12Watts lists tap counts: DAC64 1,000 (1999), QBD 18 thousand, Hugo 26 thousand (2013), DAVE 164 thousand, Hugo M Scaler 1 million; more taps and WTA improvements each improved sound. Audiophile Junkie 13:35
• 2025-05-12Watts says his Xilinx 200T FPGA has 720 DSP cores; the Quartet M Scaler he is developing to match DAVE has five 200T, two and a half thousand DSP cores. Audiophile Junkie 16:33
• 2025-09-14Watts says many studios use DAVEs, Mojo 2s and Hugos, recording engineers keep asking when the A to D converter will come out, and his son understands their needs. The Source AV 3:15
• 2025-09-14Watts says it is not a replacement for DAVE but an advanced version of the Hugo M Scaler, packed with new technology from six or 7 years of work. The Source AV 8:42
• 2026-03-17Watts says it is an M Scaler for DAVE: the upsampler feeds DAVE. needs context ecoustics 22:11
• 2026-03-17Watts says DAVE's filter is 164 thousand taps; an M Scaler adds a million taps, converting 48 kHz to 768 kHz (16 times), and DAVE then upsamples to 2048 times. ecoustics 23:40
• 2026-03-17Watts says the signal reaches analog via the noise shaper; a scaler replaces the DAC's front-end filter, and every DAC from a $600 Mojo to a $20,000 DAVE benefits. ecoustics 24:23
• 2026-03-17Watts says reflections' amplitude and timing must be perfect, with no lower limit to errors that damage depth, which he learned developing DAVE in 2014. ecoustics 33:25
• 2026-03-17Watts explains that a 32-bit signal cannot drive millions of switches, so a noise shaper reduces it to about 4.5 or 5 bits for, in DAVE's case, twenty switches. ecoustics 34:09
• 2026-03-17Watts says he thought 200 dB, versus 140 dB in chip DACs, was over-specified, but DAVE's larger FPGA finally gave him capacity to try better. ecoustics 35:41
• 2026-03-17Watts says a cello recorded four meters away sounds two meters on DAVE and 2.5 to 3 with Quartet; commercial ADCs noise-shape to 140 dB, his ADC about 301 dB. ecoustics 45:04
• 2026-03-17Watts says the expensive scaler for DAVE has 'five two hundred T' FPGAs and a 75 amp supply that can create a lot of noise, which he had to keep from corrupting the DAC. ecoustics 1:10:13
• 2026-03-17Watts says many DAVE sales, and Quartet sales once people have heard it, came from people who started with a $650 Mojo and heard something new. ecoustics 1:18:21
• 2026-03-17Watts says many start with Mojo 2 and end with DAVE, and understanding why things change the sound lets him spend resources on what improves it as budgets rise. ecoustics 1:19:05
• 2026-03-17Watts says he listened to a Mojo through Quartet last week and it transforms a Mojo as much as it does DAVE. ecoustics 1:25:47
• 2026-03-24Watts says DAVE is currently the best DAC in the world for transparency, but Quartet puts DAVE in a completely new category, improving everything about the sound. Audio Force 5:09
• 2026-03-24Watts says DAVE is unique among high-end DACs because it is over 10 years old. Audio Force 18:45
• 2026-03-24Watts says DAVE's transparency needs no Quartet to appreciate, and Chord has had no need to change it while competitors replace products every two or 3 years. Audio Force 18:55
• 2026-03-24Watts says DAVE is used in famous recording studios for its transparency, so there was no pressure to improve it, but Quartet takes DAVE to a profoundly new level. Audio Force 19:17
• 2026-03-24Watts says not imminently: there will be a future model at some stage, but not in the next year or so. needs context Audio Force 20:14
• 2026-03-24Watts says he wants people convinced by their own listening, and that every DAVE owner who has heard Quartet has been very excited, commenting they knew it would sound a lot better. Audio Force 20:38
• 2026-03-24Watts says at New York CanJam, owners of DAVE and the M Scaler all said it was a much bigger change than they expected. needs context Audio Force 21:35
• 2026-05-03Watts says major studios use Chord DAVE (transcribed 'CordDave'; possibly 'Chord DACs') for its transparency, and recording engineers ask when he will make a pulse array A to D converter. Audio Force 15:17
• 2026-10-02Watts says balanced has benefits and disadvantages; DAVE has both balanced and single-ended outputs, and sometimes one is better, sometimes the other. HiFi Buys 1:08:15
• 2026-10-02Watts says designing DAVE in 2014 with a much bigger FPGA and spare capacity, he believed noise shapers needed 200 dB in-band performance, better than 32-bit accuracy. HiFi Buys 1:17:08
• 2026-10-02Watts says DAVE, 11 years old next May, is still the best depth-resolving DAC at any price because its noise shaper runs at 104 MHz. HiFi Buys 1:23:25
• 2026-10-02Watts says forum reports of USB sources sounding different led to galvanic isolation on DAVE, the first product with it, still at 768 kHz. HiFi Buys 2:23:47
• 2026-10-02Watts says M Scaler impressions vary with systems; Class D amps or poor speakers hide it, while DAVE, Hugo 2, TT or Mojo 2 with headphones give full control. HiFi Buys 2:24:19
• 2026-10-11Watts says he cannot discuss future development, but Quartet puts DAVE in a different league musically, as shown when a prototype was shown at Munich just over 2 years ago. Distorsiuni Interioare 1:17:34
• 2026-10-11Watts says at Munich an ex-DAVE owner who had bought another DAC heard it and said he would have to buy a DAVE again. Distorsiuni Interioare 1:18:14
• 2026-10-14Watts says DAVE and Mojo are his most famous, Mojo for audiophile performance at a phone-like price, but Quartet is his most important design, partly for its built-in ADC. Part-Time Audiophile 1:03:03
• 2026-10-17Watts says it is a completely different, much more expensive product than DAVE, shelved because Quartet's lessons were more valuable, and the pro audio project is very exciting. needs context article, Oct 2026
• 2026-10-17Watts says Chord compared a turntable and phono stage direct to a preamp against going through Quartet and DAVE; the digital route sounded a lot better, which puzzled him. article, Oct 2026
• 2026-10-17Watts says removing out-of-band noise outweighs the transparency losses of DAVE and Quartet, and an analog filter cannot do it transparently, so analog should stay simple. article, Oct 2026
• 2026-10-17Watts says DAVE is the right partner but not the perfect DAC; claiming perfection then releasing a better one would make him a liar. needs context article, Oct 2026
• 2026-10-17Watts says Quartet with DAVE is the best DAC combination today for emotional engagement and hearing the recording as an original musical event. article, Oct 2026
• 2026-10-17Watts recounts a customer who sold his DAVE hearing a Munich prototype and saying it made DAVE a new category, so he would buy another DAVE. article, Oct 2026

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