DSD: playback and DSD vs PCM

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Everything he said on this topic (160)

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2014-04-01Watts says Hugo seems to sound better over months, possibly his brain adapting, but tests of old versus new units show little difference; DoP is decoded on all inputs. Head-Fi, Apr 2014
2014-04-01Watts says Hugo decodes DoP after input selection, and its FPGA SPDIF receiver should run at 384 kHz, untested on hardware, allowing DSD128 over coax once sources exist. Head-Fi, Apr 2014
2014-04-16Watts compares PCM and DSD strengths and weaknesses, says a long filter fixes PCM timing while DSD loses low-level detail, and explains why Hugo filters DSD to PCM. Head-Fi, Apr 2014
2014-04-16Watts says he has heard bad DSD and bad PCM, advises playing a recording in its original format, and says without a WTA filter he would likely prefer DSD. Head-Fi, Apr 2014
2014-04-16Watts says any input supports DoP, he heard no difference between glass and plastic optical on red-book, but glass may be needed if DoP at 176.4k is unreliable. Head-Fi, Apr 2014
2014-04-27Watts explains why native DSD inside a DAC is a bad idea, recounting PDM1024 and pulse array history, and details Qute's DSD filter and Hugo's 140 dB decimation filter. Head-Fi, Apr 2014
2014-06-02Watts relays that Android DSD may be fixed soon, says Hugo's DSD filter uses two custom DSP cores and converts DSD back to DXD, beyond computer converters. Head-Fi, Jun 2014
2014-06-02Watts says Hugo in essence converts DSD back to the original DXD master with the DSD HF distortion and noise removed. Head-Fi, Jun 2014
2014-06-02Watts says DSD64 and DSD128 HF noise must be filtered digitally, criticizes judging Hugo's decimation in theory, and says he AB tested it against a non-decimating filter. Head-Fi, Jun 2014
2014-06-03Watts says blanket claims like "native DSD is best" are usually wrong, that audio is too complex to judge without careful AB listening tests, and that such tests overturned his own assumptions. Audiophile Style, Jun 2014
2014-06-19Watts compares Pink Floyd 'Wish You Were Here' on CD and DSD via Hugo; CD had better depth, separation and rhythm, scoring 2-0 to CD. Head-Fi, Jun 2014
2014-06-19Watts says it is best to buy the master tape's format; Floyd was analog so either is legitimate, but a Norah Jones DSD sounded dreadful, likely converted from CD. Head-Fi, Jun 2014
2014-07-26Watts says live acoustic music, not analog tape, is the reference, and that DSD is limited: his noise shaper tests improved up to ten trillion times DSD's resolution. Head-Fi, Jul 2014
2014-08-03Watts says he is not a Red Book fan as such, but Hugo handles its problems better; he has heard very good DSD from '70s analog tape, and awful DSD. article, Aug 2014
2014-08-03Watts says DSD64 and DSD128 are severely limited formats, while DXD and Red Book are limited by implementation, and properly implemented Red Book will outperform DSD. article, Aug 2014
2015-02-15Watts says DSD modulators become unstable above -6 dBFS, so Hugo's DSD filters keep that headroom and internally raise volume by +6 dB to preserve gain. Head-Fi, Feb 2015
2015-02-15Watts says DSD should not be quieter on Hugo, since test tones converted to DSD were level-matched to PCM and with the +6 dB boost levels were identical. Head-Fi, Feb 2015
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
2015-09-25Watts 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
2015-10-03Watts 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 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
2015-11-21Watts 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
2015-11-24Watts 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
2015-12-17Watts 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
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
2016-05-22Watts says native DSD has much lower processor overhead than DoP and is less likely to tick or mute when data is in error. Head-Fi, May 2016
2016-05-22Watts says Chord knows no way to send native DSD on OS X, driverless UAC2 cannot resend faulty data like the Windows driver, and JRiver and Foobar played DSD glitch-free. Head-Fi, May 2016
2016-05-24Watts states that Hugo accepts DSD via DoP only. 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
2016-07-24Watts 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
2016-11-28Watts 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
2017-01-09Watts says it accepts DoP DSD64 and DSD128 but nothing higher because the SPDIF input is limited to 384 kHz. needs context Head-Fi, Jan 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
2017-03-15Watts says white to green sounds warmer, and DSD noise shapers delay small transients by tens of microseconds, giving DSD a soft, warm sound; he leaves the filter on green. Head-Fi, Mar 2017
2017-03-28Watts says a link is bit perfect or obviously failing, suggests DoP DSD as a test, and says glitches usually come from the source processor. Head-Fi, Mar 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
2017-09-24Watts says DSD256 DoP is sent as 705 kHz, drop-outs mean the source cannot pack DoP in real time, native DSD is easier, and Davina 768k recordings may follow. Head-Fi, Sep 2017
2017-10-13Watts says DSD has amplitude-related timing errors: small transients take longer through the noise shaper than large ones, so DSD sounds soft. miceblue425 59:21
2017-12-05Watts says R2R switches change most for small signals, adding glitch energy that degrades small-signal integrity and depth; he calls DSD widely misunderstood, though he loves it. RMAF 33:54
2017-12-05Watts says a PDM 256 DSD DAC, heard in 1989, was the first digital to sound warm and refined to him, though he doubted 256 pulses could reconstruct 20 kHz. RMAF 34:44
2017-12-05Watts says the explanation of noise shaping pushing noise out of band made no sense to him and is wrong, so he spent a lot of time understanding noise shapers. RMAF 35:33
2017-12-05Watts says DSD avoids resistor mismatch and higher-order harmonics, giving fairly good depth and refinement, while R2R's higher-order harmonics sound hard, forced, aggressive and flat to him. RMAF 35:56
2017-12-05Watts says the DSD modulator creates noise floor modulation in the digital domain, with DSD64 at about 110 to 126 dB versus the 350 dB his DACs need. RMAF 36:37
2017-12-05Watts says DSD sounds flat in soundstage versus PCM on his DACs; it needs no WTA filter but has timing problems, as tiny transients leave the modulator output unchanged. RMAF 37:24
2017-12-05Watts explains how a fifth-order DSD modulator's integrators slowly build up error before the output changes, taking twenty or 30 microseconds for a minus 60 dB signal. RMAF 38:21
2017-12-05Watts says DSD degrades small-signal timing, and transient timing errors blur transients so music sounds soft, which is why 2L DSD versions sound softer and warmer than DXD. RMAF 39:08
2017-12-05Watts says DSD sounds fat as it cannot resolve small signals and has signal-dependent switching; his PDM DACs measured 95 to 100 dB and needed per-unit tweaking with capacitors. RMAF 39:52
2017-12-05Watts says a DSD noise shaper is fundamentally unstable away from zero because it would need to output plus two at times, which 1-bit DSD does not allow. RMAF 43:47
2017-12-05Watts says clamping makes DSD's noise shaper unstable unless first order, whereas pulse array allows overload so its noise shaper works; the coefficients strongly affect measurements and sound. RMAF 44:33
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
2017-12-25Watts 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
2017-12-25Watts rejects the claim that DSD needs no DAC, saying a simple low-pass filter would have huge THD and noise, and his DSD DAC designs never measured reasonably. Head-Fi, Dec 2017
2017-12-26Watts says his aim is the sound of unamplified music, not analog or vinyl sound, and that DSD fails at this because the format is not transparent. Head-Fi, Dec 2017
2018-01-03Watts says Hugo 2 filters DSD to 705.6 kHz PCM with an improved filter needing over 200 dB attenuation, so performance is limited only by the DSD itself. 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
2018-01-04Watts says gate count is the reason: crossfeed runs serially at 16FS, but DSD512 would need costly parallel DSP, and the new filter removes the need for DSD plus mode. Head-Fi, Jan 2018
2018-01-11Watts says ASIO is not supported on iOS, and dropouts come from the source sending faulty DoP data; the DAC now gives a tiny tick instead of a full mute. Head-Fi, Jan 2018
2018-01-15Watts says upsampling PCM to DSD256 will sound much worse than feeding the original PCM to Qutest, for several reasons. Head-Fi, Jan 2018
2018-05-04Watts says his DSD filters reconstruct the analog signal, but DSD's lost timing information cannot be repaired; Hugo 2's improved DSD filter softened his stance though he prefers Redbook. Head-Fi, May 2018
2018-05-05Watts explains 1-bit DSD noise shapers are signal-dependent and unstable, unlike N-bit designs; Davina's N-bit pulse array ADC has 400 dB noise shaper performance and signal-independent activity. Head-Fi, May 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
2018-05-13Watts 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
2018-05-20Watts says it supports native DSD up to DSD 512 via the ASIO driver and DoP up to DSD 256; he does not know about Linux. Head-Fi, May 2018
2018-05-21Watts says Chord confirmed ASIO is Windows only, so on Linux DSD is DoP only. Head-Fi, May 2018
2018-05-22Watts says Linux needs varied drivers for native DSD while DoP is driverless but less efficient, capping it at DSD 256; his DSD 512 track sounds flat and soft. Head-Fi, May 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
2018-06-30Watts explains decimation needs low-pass filtering to avoid aliasing; decimating DSD to 705/768 kHz saves FPGA space, and Hugo 2's filter beats non-decimating DSD+ through better RF removal. Head-Fi, Jun 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
2018-07-30Watts says it does DSD512 on USB, 384 on coax, and 768 with dual coax. needs context Head-Fi, Jul 2018
2018-08-02Watts says Blu 2 and M scaler filter code is identical, explains that upscaling recovers transient timing rather than adding information, and why pulse array needs DSD converted to PCM. 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 Blu Mk2 has the same DSD filter, and the Hugo M Scaler began as a copy of the Blu 2 project with only control code changed. Head-Fi, Aug 2018
2018-08-14Watts says all his DACs can do it, but limited to DSD128 if the source can deliver that. needs context Head-Fi, Aug 2018
2018-08-16Watts says the new DSD decimation filter sounds slightly better than DSD+ through better RF suppression; Davina work showed decimating to 16FS is lossless if aliasing stays below -220 dB. Head-Fi, Aug 2018
2018-08-17Watts confirms DSD64 has only 64 one-bit pulses per 44.1 kHz-equivalent sample, which is why its high-frequency resolution is innately not good enough. Head-Fi, Aug 2018
2018-09-16Watts says DSD sounds soft and warm because its delay depends on amplitude, by tens of uS; he advises against software PCM upsampling, and mentions F1 in Singapore. Head-Fi, Sep 2018
2018-10-25Watts says native DSD works on the M scaler (Roon, JRiver) using Dave code if SR OP is white, else it is silent; dual data needs 50 Mbit/s per cable. 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
2018-11-07Watts says PCM can in theory recover the bandlimited signal perfectly given enough processing, hence the M scaler, while DSD is format limited and falls in a lower league. Head-Fi, Nov 2018
2018-11-16Watts lists five unsolvable DSD flaws (jitter sensitivity, signal-correlated switching, poor small-signal resolution, amplitude-dependent delay, instability) that led him from PDM 256 to the pulse array in 1995. Head-Fi, Nov 2018
2018-12-12Watts says a DSD output's switching varies with signal; each switch makes glitch noise, plus N/P FET speed asymmetry, so signal-dependent glitch noise creates distortion and noise floor modulation. Pursuit Perfect System 16:35
2019-01-09Watts says JRiver on Windows 10 with Chord's ASIO driver plays DSD512 without clicks, and relays Chord's Matt's Mac advice: stop backups, change USB port, try Roon. Head-Fi, Jan 2019
2019-02-06Watts says true DSD has no decimation filter, conventional decimation gives about 20 dB rejection, and his FIR decimation is below -300dB; fractional 705/768 decimation was the problem. Head-Fi, Feb 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
2019-02-20Watts says Qutest is surge protected, element count does not set resolution, Davina has no date, DSD sounds unnaturally soft, and explains FIR for reconstruction versus IIR for EQ. Head-Fi, Feb 2019
2019-02-22Watts says he used DSD256-equivalent PDM DACs with 32 elements in the early 90s and invented pulse array to fix DSD's resolution, noise floor modulation and amplitude-dependent timing. Head-Fi, Feb 2019
2019-03-08Watts says the M scaler converts DSD to 705 kHz PCM, output only via dual BNC; in hindsight he could have passed DoP through, and TT2 solves this. Head-Fi, Mar 2019
2019-05-18Watts gives three reasons DSD must be converted to PCM, notes Chord knows of the Linux DSD512 issue, and says 44.1 via M scaler sounds better. Head-Fi, May 2019
2019-05-19Watts says DSD-to-PCM is not lossless; his Hugo 2, TT2 and M scaler filters exceed 200dB rejection with -301 dB truncation, against about 60 dB in chips. Head-Fi, May 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
2019-06-14Watts says timing errors cannot be recovered once introduced, and in DSD small-amplitude steps are delayed longer through the modulator than large-signal steps. Head-Fi, Jun 2019
2019-06-21Watts explains how delta-sigma ADC modulators work, why 1-bit DSD modulators lack headroom, cannot be dithered and delay small signals more, and says pulse array and Davina avoid this. Head-Fi, Jun 2019
2019-07-20Watts says Qutest, like all his DACs, decodes DoP over SPDIF, so DSD64 works over optical, which is its maximum there. Head-Fi, Jul 2019
2019-09-23Watts explains he avoids native DSD conversion for jitter sensitivity and noise, and that DoP (to DSD256) and native ASIO transmission (to DSD512) deliver identical data. Head-Fi, Sep 2019
2019-12-10Watts says chip DACs are all n-bit delta sigma with noise shapers around 3 MHz, and that before 1995 designers chose between Philips R2R chips and 1-bit PDM chips. Passion for Sound 4:42
2019-12-10Watts says chip makers abandoned 1-bit DSD/PDM in the mid nineties for its instability, distortion, noise, gurgle tones and modulation noise, so Sony and Philips's DSD was a backward step. Passion for Sound 5:25
2019-12-10Watts says DSD was a backward step for digital-to-analog conversion, and that he was rejecting DSD in 1995 when he created his Pulse Array DAC technology. Passion for Sound 6:13
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
2020-01-18Watts says Hugo 2 is Class A into 300 ohms at 5v RMS, AB into lower loads, and explains DSD volume needs another noise shaper because DSD is 1-bit PCM. Head-Fi, Jan 2020
2020-01-28Watts says DSD adds softness because small-signal steps are delayed more than large ones, blurring transients, has poor depth from small-signal accuracy, and advises fixing hardness rather than using DSD. Head-Fi, Jan 2020
2020-01-29Watts advises PCM unless an SACD's master was DSD, says he is making mains-powered USB match optical and battery, and warns modifying his optimized designs more likely harms than helps. Head-Fi, Jan 2020
2020-01-30Watts agrees DSD may beat PCM on a modest DSD-optimized chip DAC, but says PCM is much better on Hugo 2, DSD being format limited and PCM conversion limited. Head-Fi, Jan 2020
2020-07-28Watts says low gain sounds slightly different from high gain due to two extra feedback components, and ASIO is preferred for DSD512, possibly with less processing than WASAPI. Head-Fi, Jul 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
2020-11-24Watts says DSD256 modulator noise is around -30dB at 500kHz against -130dB for Hugo 2, and that his plots differ because he uses 0dBFS white noise, not swept sine. 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
2021-05-18Watts says the M scaler and TT2 share identical DSD code, DSD's damage to transients and small signals cannot be repaired, but their DSD filters remove its HF noise. Head-Fi, May 2021
2021-05-22Watts says all DSD speeds have problems; DSD256 beats DSD64 but not WTA PCM, and two-level modulators cause noise floor modulation that needs at least 3-bit modulation. Head-Fi, May 2021
2021-05-22Watts says DXD is fine since it is regular PCM at 352.8kHz, provided the original ADC was n-bit rather than 1-bit. Head-Fi, May 2021
2022-02-07Watts says he mainly uses DCA Aeon 2 Closed, and Mojo 2 uses the original Mojo DSD filter because 98% of FPGA resources were used, though its HF filter helps. Head-Fi, Feb 2022
2022-02-20Watts says USB latency is insignificant against WTA latency, DoP works to DSD256 on Linux and macOS, native DSD512 needs Windows ASIO, and 44.1/16 with M Scaler beats DSD512. Head-Fi, Feb 2022
2022-02-21Watts says good 16-bit 44.1 via the M Scaler beats DSD512, which sounds soft and flat like all DSD, consistent with DSD's small-signal, timing and noise floor modulation problems. Head-Fi, Feb 2022
2022-02-21Watts says DSD is filtered and converted to 705.6 kHz PCM before the UHD DSP, so EQ, crossfeed and volume work identically. Head-Fi, Feb 2022
2022-03-19Watts calls DSD a nightmare: 10 microseconds of phase shift errors, noise floor modulation from 130 dB to 115 dB at DSD64, and too few pulses, so it sounds soft. MFG Audio Reviews 53:59
2022-03-19Watts says DSD cannot reproduce -140 dB, DSD256 and 512 are better but all 1-bit DSD has noise floor modulation, and decent performance would need around DSD 16,000. MFG Audio Reviews 54:40
2022-03-19Watts says PCM sounds crappy on a crappy DAC but spectacular on a DAC that solves these issues, so PCM is potentially unlimited while DSD is moderate for everything. MFG Audio Reviews 55:24
2022-05-14Watts says WTA taps split between future and past; M scaler video mode uses 98,304 future and 507,904 past taps (606,208 total); ASIO native USB allows DSD512, with fewer pops. Head-Fi, May 2022
2022-07-11Watts says M Scaler DSD handling matches Hugo 2 and TT2, converting DSD64 through DSD512 to 705 kHz 24-bit; he also praises forum civility and calls audiophile patents marketing. Head-Fi, Jul 2022
2022-07-12Watts says optical output from his Windows 10 PC's MSI motherboard, and from his old MSI laptop, handles 88.2, 176.4 and DoP DSD64 without problems. Head-Fi, Jul 2022
2023-02-04Watts says to check bit perfection, send a DSD file as DoP, which decodes only if bit perfect; JRiver or Roon reports can be trusted. Dusty Audio 1:05:36
2023-02-04Watts advises owners to check with a DSD file: if it plays as DSD, the path is bit perfect. Dusty Audio 1:10:46
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
2023-03-28Watts says DSD's single element avoids R2R mismatch, and its distortion disappears below about -60 dB as signals get smaller, matching how the ear behaves. The Headphone Show 19:51
2023-03-28Watts says DSD's 1-bit limit denies the noise shaper the overload it needs, causing internal overloads or instability and hence noise floor modulation. The Headphone Show 20:39
2023-03-28Watts says DSD64 has 115 to 125 dB of noise floor modulation, though he hears it at -350 dB; DSD cannot dither its quantizer and has linearity problems. The Headphone Show 21:26
2023-03-28Watts says DSD's linearity problems degrade depth, DSD64's noise shaper reaches about -126 dB, and though DSD needs no sinc filter, large signals pass its quantizer faster than small ones. The Headphone Show 22:11
2023-03-28Watts says small DSD transients come through later than large ones, which is why DSD sounds soft and warm as the brain blurs transients; he also cites idle pattern noise. The Headphone Show 23:01
2023-03-28Watts says DSD64's -20 dB of noise at 100 kHz would overload analog circuits or cause noise floor modulation, so filtering it, effectively converting to PCM, beats a DSD-only DAC. The Headphone Show 52:31
2023-03-28Watts says PCM also allows EQ, crossfeed and digital volume, which DSD cannot; analog volume adds problems, and his volume controls are transparent, passing the -301 dB test. The Headphone Show 53:18
2023-03-28Watts says he wishes studios would not record in DSD; he is testing his own pulse array ADC and making recordings to compare reproduction with the live sound. The Headphone Show 53:51
2024-05-31Watts says he is not under contract with Chord, a scaler needs physical separation from the DAC, DSD sounds unreal, and subjective impressions can be characterized objectively. Head-Fi, May 2024
2024-06-24Watts defers Quartet's 4M-tap details to launch, says 5.2 uS at 192kHz is still too big, calls DSD a mess for timing, and describes his reference tracks. Head-Fi, Jun 2024
2024-06-26Watts says DSD256 has -20dB noise at 400kHz, all DSD rates show large modulator noise floor modulation, the brain perceives any timing change, and recordings stay limited to 192k. Head-Fi, Jun 2024
2024-06-26Watts says DSD modulators carry about -20dB HF noise at 100kHz for DSD64, too high, noting a -350dB difference at 10MHz was audible blind. Head-Fi, 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 DSD's distortion falls as signal falls, matching how the ear works, whereas R2R distortion stays fixed and can exceed very small signals. HIFICLUB 37:45
2024-07-12Watts says DSD64 is very noisy at high frequencies (about minus 20 dB near 100 kHz), with signal-correlated noise that damages transient timing. HIFICLUB 38:29
2024-07-12Watts says DSD sounds unnaturally warm and soft from poor transients, and its full-scale 1-bit swing makes it very sensitive to clock jitter. HIFICLUB 39:15
2024-07-12Watts says DSD's switching activity varies with signal, causing noise floor modulation, and its 64 times noise shapers reach only 130 dB, so minus 301 dB is impossible. HIFICLUB 39:59
2024-07-18Watts says his DSD-to-PCM filter is a separate module with over 220dB rejection, explains DSD's correlated out-of-band noise, and says he now streams PCM from Qobuz instead of DSD. Head-Fi, Jul 2024
2024-11-11Watts advises sending bit-perfect data in its mastered format, calls DSD technically flawed, and says he uses Hugo 2 with Stealth, so Mojo 2 will drive Stealth fine. Head-Fi, Nov 2024
2025-03-27Watts says DoP works on all inputs within rate limits (optical DSD64, coax up to DSD128), conversion keeps DSD's 6dB overload, and test modulators show DSD is technically unacceptable. Head-Fi, Mar 2025
2026-03-17Watts says DSD is a poor archiving format: DSD64 has huge out-of-band noise, -20 dB at 100 kHz, and too few pulses create timing errors, whereas PCM encodes information perfectly. ecoustics 28:09
2026-03-17Watts says PCM from a good ADC holds timing perfectly, leaving reconstruction as the DAC's problem, while DSD corrupts timing in the recording itself and adds noise floor modulation. ecoustics 29:05
2026-03-17Watts says DSD sounds artificially soft and loses depth through poor small-signal accuracy, then begins explaining how finely the brain perceives depth, as with a phone moved half an inch. ecoustics 29:55
2026-10-02Watts says DSD sounds natural as distortion vanishes into noise, but he wanted its benefits without its problems: a faster noise shaper and no signal-dependent switching causing NFM. HiFi Buys 1:42:15
2026-10-11Watts says aliasing matters because out-of-band signal-correlated noise degrades transient timing, and Quartet's DSD decimation follows its ADC decimation process. Distorsiuni Interioare 56:10
2026-10-11Watts says the stronger decimation makes DSD converted to PCM sound better; going from 64FS to 16FS, DSD's high-frequency distortion must be removed. Distorsiuni Interioare 57:07
2026-10-11Watts says DSD's distortion near full modulation degrades transients; near-perfect decimation has no downside, but DSD conversion itself creates transient timing errors. Distorsiuni Interioare 57:50
2026-10-11Watts says these baked-in errors make DSD sound unnaturally soft and flatter in depth than good PCM and cannot be recovered, which is why he opposes DSD. Distorsiuni Interioare 58:38
2026-10-11Watts says DSD was meant to allow volume and EQ in DSD, but reconverting to DSD caused cumulative losses so large that it was impractical. Distorsiuni Interioare 59:19
2026-10-11Watts says this exposes DSD as not a transparent process. Distorsiuni Interioare 1:00:04
2026-10-11Watts says such players convert DSD to PCM and apply the EQ in PCM. Distorsiuni Interioare 1:00:20
2026-10-11Watts confirms they convert back to DSD. needs context Distorsiuni Interioare 1:00:28