Hugo TT2: everything he said

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

• 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
• 2018-05-11Watts says TT2 is not wasted on easy-to-drive headphones, since it also brings improved noise shapers for better depth and 98k WTA taps. needs context Head-Fi, May 2018
• 2018-05-11Watts gives just over 18V RMS at 1% THD in amp mode and 5V in DAC mode, estimates 98 dB from LS3/5a speakers, and explains why supercaps replace batteries. Head-Fi, May 2018
• 2018-05-12Watts lists TT2 output options (DAC mode 2.5V RCA/5V XLR, low gain 3V, volume at -3dB) and recounts how the DX amp's output stage was adopted in TT2. 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
• 2018-05-14Watts says machined metalwork is the largest bill-of-materials cost but nowhere near 50%, and lists its benefits: no steel hysteresis, RF rejection, heat removal and vibration control. Head-Fi, May 2018
• 2018-05-14Watts says TT2 has an FPGA 5 times as capable as the original TT's and twice Hugo 2's, a 98,000-tap WTA filter, a more advanced noise shaper, and 30 farads of supercaps. HIFICLUBE.NET JVH 7
• 2018-05-14Watts says the supercaps give the output stage ample current; it was upgraded after the TT was found used with efficient loudspeakers, so TT2 can drive them directly. HIFICLUBE.NET JVH 50
• 2018-05-14Watts says the output delivers 18 watts, and 7 watts from the single-ended output, enough to drive efficient loudspeakers; modest 90 dB speakers will do (transcript partly garbled). HIFICLUBE.NET JVH 1:16
• 2018-05-15Watts says amp mode on TT2 is for driving efficient speakers or replacing a pre-amp as a digital pre-amp, and suggests low gain mode for that. 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 he finished TT2's output stage optimization for production, measuring 0.000195% THD at 20Hz unchanged with an 8 ohm load at 12W. Head-Fi, May 2018
• 2018-05-17Watts says all mains-powered DAC/amps have isolation, USB sounds very close to optical, he is amazed 2Qute can drive a loudspeaker, and he explains his single-stage output amplifier. Head-Fi, May 2018
• 2018-05-18Watts says TT2's power consumption out of standby, excluding the PSU, is 13W with no outputs connected, pending official Chord figures. Head-Fi, May 2018
• 2018-05-19Watts says balanced drive gives headphones no benefit, so use TT2's XLR only for voltage or power needs, balanced power amps or loudspeakers; HD800S are easy to drive. Head-Fi, May 2018
• 2018-05-20Watts explains TT2's 18V RMS balanced output, estimates power into 6 ohms, describes the supercaps and second-order analog noise shaper benefits, and says the output is protected. 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 explains TT2's digital DC servo with no coupling caps, confirms separate crossfeed for headphone and amp/DAC modes, and says -3dB volume equals 3V RMS as on Dave. Head-Fi, May 2018
• 2018-05-23Watts links a 4mm in-line socket cable set for TT2's balanced 18W output and calculates that 100 dB SPL at 1m needs 88 dB speaker sensitivity. Head-Fi, May 2018
• 2018-05-24Watts says TT2 would reach 103 dB on a 91 dB speaker, the balanced output has double the impedance, and SE would give 114 dB with an LCD-4. Head-Fi, May 2018
• 2018-05-24Watts says TT2 drives 1 ohm loads fine and should give 27W RMS into 4 ohms from the balanced XLR output. needs context 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's output stage uses emitter degeneration and safety resistors, and will not clip at or below +6dB with CD into 8 ohms SE, or +12 dB with Blu-ray. 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
• 2018-06-17Watts says TT2's gain control applies to all outputs with separate remembered settings, and low gain limits output to 2.5V RMS and lowers residual noise for IEMs and power amps. Head-Fi, Jun 2018
• 2018-06-23Watts says the linked XLR adaptors look fine for an HD800 on TT2 but adaptors noticeably degrade sound long term, and notes TT2's XLR outputs are male. 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
• 2018-06-25Watts confirms TT2 worked fine when run from a battery pack. needs context Head-Fi, Jun 2018
• 2018-06-26Watts says an 85Wh pack should run TT2 about 6 hours at 13W, a pack of 85Wh or more with 3A at 12 to 15V works, and batteries were avoided. 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 confirms TT2 mutes the rear RCA and XLR outputs when the headphone jack is in use. needs context Head-Fi, Jul 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
• 2018-07-03Watts says he drives his B&W 803 D3 from TT2's single-ended output with more than enough volume in a moderate room. 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
• 2018-07-09Watts says he will give two seminars: Saturday launching something new and its technology, Sunday on Hugo TT2. Head-Fi, Jul 2018
• 2018-07-15Watts confirms TT2's SE outputs are simplest and potentially most transparent, with balanced needed only for extra power, though some power amps and cables prefer XLR. Head-Fi, Jul 2018
• 2018-07-17Watts says TT2 makes no pop when switched off because its supercaps take a long time to discharge. Head-Fi, Jul 2018
• 2018-07-24Watts says with Aeon headphones he would choose the M Scaler over TT2 as an upgrade from Hugo 2, calling it transformational, unless driving difficult headphones or speakers. 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
• 2018-07-29Watts hears no difference between battery and the supplied PSU, warns non-supplied PSUs may void warranty (never above 15V), and found laptop battery vs mains and optical vs USB identical. Head-Fi, Jul 2018
• 2018-07-29Watts uses a Poweradd Pilot Pro 2 at 12V, says batteries are not worth it for TT2, and hears no change with his mobile in airplane mode. 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
• 2018-07-31Watts says it is largely immune; RF corrupting other devices is the issue, so he plugs TT2 and the source in on opposite sides of the room. Head-Fi, Jul 2018
• 2018-08-04Watts says TT2 is warmer with better depth than Hugo 2 with the M Scaler too, and integer decimation from 192 to 96 loses little with a decent filter. Head-Fi, Aug 2018
• 2018-08-04Watts clarifies that the M Scaler was used in both cases when he found TT2 better than Hugo 2 in depth and resolution. needs context Head-Fi, Aug 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
• 2018-08-05Watts says TT2's SE output gives the Abyss 2W or 121 dB SPL, the balanced 8W or 127 dB, and the balanced path's extra parts slightly reduce transparency. Head-Fi, Aug 2018
• 2018-08-05Watts says TT2 gives an HD800 270 mW or 121 dB SPL from SE, warns that 100 dB damages hearing after 15 minutes, and advises no more than 85 dB beyond 8 hours. 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
• 2018-08-07Watts says yes, by pressing the DX volume buttons together on the Hugo M Scaler, and TT2 has a DIM setting that dims everything. needs context Head-Fi, Aug 2018
• 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
• 2018-08-09Watts gives Hugo M Scaler dimensions (40.5 mm tall, 235 mm wide, 236 mm deep), its PSU size (140x50x30 mm), and TT2's 51 mm height. Head-Fi, Aug 2018
• 2018-08-12Watts says the M scaler makes compression losses audible, audiophile BNC cables sound same or worse, TT2 measures identically in Class B, and the units stack. 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
• 2018-08-27Watts says it is the volume setting, sample rate is the color through the port, and the display shows both only when they change. needs context 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
• 2018-08-29Watts says TT2's doubly isolated 15V 60W PSU works worldwide with a 2-pin mains input, and normal dissipation is 13W, more when driving speakers. Head-Fi, Aug 2018
• 2018-09-02Watts says TT2 gives 9.3V RMS at +7dB with 0dBFS, digital gain extends to +22 dB, and low gain cuts output by 9dB, including on headphone outputs. Head-Fi, Sep 2018
• 2018-09-03Watts says TT2 outperforms Class AB, showing no crossover distortion at 12W into 8 ohms thanks to its second-order analog noise shaper, and likens Chord's Etude feedforward amp. Head-Fi, Sep 2018
• 2018-09-09Watts says the HF filter and WTA2 settings are unaffected by the M scaler, which works from 1FS to 16FS, and explains the vague autumn delivery as distribution time. Head-Fi, Sep 2018
• 2018-09-16Watts says TT2 has a gain switch because its high power would leave too much noise for sensitive IEMs; low gain cuts residual noise to 1.7 uV. 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
• 2018-09-21Watts confirms TT2 remembers separate crossfeed settings for headphone mode and DAC/amp modes. Head-Fi, Sep 2018
• 2018-10-03Watts explains TT2's single-stage SE output amplifier, the relay-switched resistor that sets low gain, and the inverted stage that creates the balanced negative output. Head-Fi, Oct 2018
• 2018-10-13Watts says TT2's supercaps work from the start, he has no experience of hardware break-in and would not expect a big change, but brain break-in differs. Head-Fi, Oct 2018
• 2018-10-24Watts summarizes TT2's 10-element pulse array: 300 dB noise shapers at 104MHz, jitter insensitivity, no measurable noise floor modulation or non-linearity, and minimal analog filtering. 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
• 2018-10-28Watts explains how TT2's volume display shifts with gain mode and where it clips, and gives delays of 34 ms for Hugo 1 and 63 ms for TT2 with video. 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
• 2018-10-31Watts explains WTA1's 768 kHz output as a listening-test balance, WTA2's 256FS step shared by all current DACs except Mojo, and a three-stage IIR filter to 9.6 nS. Head-Fi, Oct 2018
• 2018-11-01Watts says 320k MP3/AAC softness is more apparent via TT2 and M Scaler, single-driver speakers are transparent but flawed, and 7W SE suffices for his 803 D3. Head-Fi, Nov 2018
• 2018-11-05Watts says red OP SR is volume-equalized pass-through, headphones won't need a DX amp, units may stay on (M Scaler auto-shutdown, TT2 standby), and announces a Hong Kong event. Head-Fi, Nov 2018
• 2018-11-06Watts says servers bring no sound-quality gain, their perceived transparency being RF noise raising noise floor modulation and brightness, while the M scaler transforms musical performance. Head-Fi, Nov 2018
• 2018-11-08Watts says whether TT2 drives the speakers depends on room and volume, noting his 803 D3 work with only the 7W SE outputs. Head-Fi, Nov 2018
• 2018-11-11Watts describes his homemade TT2 speaker adaptors and annealed 16-core PTFE silver-plated copper speaker cables, and says he mostly listens to classical, electronica and prog rock. Head-Fi, Nov 2018
• 2018-11-11Watts says his adaptors allow balanced (18W/8) or single-ended (7W/8 ohms) speaker drive, with the green terminal as ground. needs context Head-Fi, Nov 2018
• 2018-11-11Watts says TT2 can drive B&W loads dipping to 3 ohms thanks to supercap reserves and a 10A current limit, and suggests trying 7W SE before balanced. Head-Fi, Nov 2018
• 2018-11-15Watts says TT2's supercaps take 200,000 hours for a 30% capacitance loss and 1,000,000 hours to halve; headphone and RCA outputs give 7W/8 ohms, XLR 18W/8 ohms. Head-Fi, Nov 2018
• 2018-11-16Watts says he uses only the Hugo M Scaler and Hugo 2 on planes, and packs a TT2 to use with the M scaler in hotel rooms. Head-Fi, Nov 2018
• 2018-11-17Watts says TT2's 30F supercap and large inductor make the external PSU supply only DC current, isolating the electronics from mains along with RF filtering, likely helping via amplifier PSRR. Head-Fi, Nov 2018
• 2018-11-17Watts says he always uses high gain, and low gain is for when lower noise is needed. Head-Fi, Nov 2018
• 2018-11-18Watts says TT2 needs no balance control with digital volume, a 705/768 indication means the M Scaler works, and suggests a week of listening before comparing pass-through. Head-Fi, Nov 2018
• 2018-11-20Watts says the setup should be OK, as the SE amp will see currents from the sub and full-range speakers, fine if both are 8 ohms; XLR gives +6 dB more output. needs context Head-Fi, Nov 2018
• 2018-11-30Watts says there is no maximum XLR cable length since TT2's output impedance is so low, but any extra interconnect length degrades transparency. Head-Fi, Nov 2018
• 2018-11-30Watts says capacitive loads are fine, earthing it to TT2 sounds like a good idea, and the phono outputs disconnect only when a headphone jack is inserted. needs context Head-Fi, Nov 2018
• 2018-11-30Watts clarifies that TT2 will drive all capacitive loads from 0 pF to 1 uF. Head-Fi, Nov 2018
• 2018-12-06Watts says TT2 is more transparent and refined than Hugo 2, the refinement being more apparent, so pass-through differences may be more noticeable with TT2. Head-Fi, Dec 2018
• 2018-12-11Watts says TT2's LED flash after mains power-up is the FPGA booting with tri-stated outputs, harmless, but he recommends using the front-panel standby switch instead. Head-Fi, Dec 2018
• 2018-12-11Watts says the supercaps are in TT2 and he wouldn't bother with another PSU, since disconnecting the supplied one is inaudible; linear PSUs sound falsely brighter and measure worse. Head-Fi, Dec 2018
• 2018-12-12Watts says a conventional DAC uses four amplifiers versus his one, says TT2 has a 10-element pulse array, and explains elements as ten offset 1-bit streams whose clock edges cancel. Pursuit Perfect System 32:30
• 2018-12-12Watts says every circuit point has RF decoupling, with quad-layer ground planes, a digital PLL eliminates source jitter, and TT2's noise floor is minus 178 dB with zero measurable NFM. Pursuit Perfect System 34:53
• 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 a high output voltage lets it drive any headphone; supercaps, as in the original Hugo TT, on both rails with an inductor mean the supply draws only DC. Pursuit Perfect System 37:27
• 2018-12-12Watts says TT2's inexpensive supply was customized after trying four or five to match battery performance; batteries sound warmer because they lack mains RF noise, which creates NFM. Pursuit Perfect System 38:09
• 2018-12-12Watts says RF-induced NFM sounds brighter and is mistaken for transparency but becomes tiring within an hour; he then states TT2 gives 9.3 V RMS and five amps of current. Pursuit Perfect System 38:55
• 2018-12-12Watts says TT2's linear output current suits efficient speakers; it gives 7 W, or 18 W into 8 ohms balanced, and has a low-noise low gain mode for IEMs. Pursuit Perfect System 39:38
• 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 says TT2 has 90,000 taps, then recounts studying electronics as a science degree and reading about the physiology of hearing in a nearby psychology lab. Pursuit Perfect System 10:56
• 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 advises against replacing TT2's supplied PSU, saying he hears no change when it is pulled for 10 seconds and an earthed supply would likely degrade 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
• 2019-01-06Watts says the symptom is the PSU entering hiccup mode from supercap charge currents, meaning either a faulty PSU or a fault in TT2. needs context Head-Fi, Jan 2019
• 2019-01-08Watts says the M Scaler's FPGA die runs only a few degrees above the chassis, about 45 C when stacked, far below its 125 C rating, so reliability is unaffected. Head-Fi, Jan 2019
• 2019-01-09Watts gives TT2 distortion figures, 0.042 ohm output impedance and low-gain voltages, notes no distortion above 3 kHz at 12 W, and says the FPGA sits die-down on the chassis. Head-Fi, Jan 2019
• 2019-01-10Watts says distortion does not differ between TT2 gain modes below clipping, and to use high gain above 2.5 V single-ended or 5 V XLR. Head-Fi, Jan 2019
• 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
• 2019-01-12Watts says TT2's XLR output in low gain is slightly higher than Hugo 2's, 6.6 against 5.4 V RMS. Head-Fi, Jan 2019
• 2019-01-16Asked whether TT2's RCA and XLR outputs can be used together in amp mode, for a sub and an amp, Watts says yes. Head-Fi, Jan 2019
• 2019-01-21Watts drives B&W 803D3 from TT2 single-ended via XLR pins 1 and 2, explains the third-order filter to 2048FS, and uses green for his 96k recordings. Head-Fi, Jan 2019
• 2019-01-23Watts says TT2's amp mode and headphone mode use identical hardware apart from connectors and FPGA configuration, so output is the same with identical settings. Head-Fi, Jan 2019
• 2019-01-24Watts maps TT2 filters to colors: filter 1 white (as Hugo 2), filter 2 green, filter 3 orange, filter 4 red. Head-Fi, Jan 2019
• 2019-01-31Watts says TT2 supercaps last over 11 years, it can stay on, warm-up takes about 10 minutes, pre-amps cost transparency, and linear PSUs at best sound the same. Head-Fi, Jan 2019
• 2019-02-04Watts says TT2 driving headphones draws about the same power as the M Scaler, giving about 6 to 7 hours from a Poweradd Pilot Pro 2. Head-Fi, Feb 2019
• 2019-02-05Watts says balanced adds complexity that affects transparency, but its benefit depends on cables, length and gear, so he advises trying both. 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
• 2019-02-22Watts says TT2 and M Scaler USB inputs are galvanically isolated, drawing about 250 mW from the source, which may drain a phone about 15% faster. Head-Fi, Feb 2019
• 2019-02-25Watts says battery power is the reference, optical and USB sound nearly identical on the M scaler, TT2 gains nothing from batteries, and 10 minutes of warm-up is needed. Head-Fi, Feb 2019
• 2019-02-26Watts says TT2 is built like mobile products, his has flown 250,000+ km in luggage, and he carries the M Scaler as carry-on without security issues. Head-Fi, Feb 2019
• 2019-03-04Watts says removing harmonic distortion while ignoring noise floor modulation sounds bright and analytical, while eliminating noise floor modulation restores warmth, and shares TT2 measurements. Head-Fi, Mar 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
• 2019-03-12Watts says to consider TT2's balanced output only at +6H or above, and its low gain setting is about 6 dB quieter than Mojo. Head-Fi, Mar 2019
• 2019-03-13Watts lists TT2's advantages over Qutest: better noise shapers, DAVE reference circuitry, a second-order analog noise shaper, and a far simpler path than Qutest plus headphone amp. Head-Fi, Mar 2019
• 2019-03-18Watts explains TT2's output amplifier as a second-order analog noise shaper replacing a nested feedback loop, giving huge HF gain and no distortion above 3 kHz. Head-Fi, Mar 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
• 2019-03-29Watts says TT2 filters are interpolation tweaks not EQ, argues NOS DACs are not truly bit perfect, explains transient timing errors, and warns IIR EQ and dithered volume are not transparent. Head-Fi, Mar 2019
• 2019-04-10Watts explains TT2's volume display shows absolute output, so switching gain changes the reading by 9 dB, and gives clipping points of -2L and +7H. Head-Fi, Apr 2019
• 2019-04-11Watts says TT2's gain switch changes the output amplifier's gain, giving just over 3 V RMS low and 9.3 V RMS high, with the volume calibrated to actual output. Head-Fi, Apr 2019
• 2019-04-11Watts says TT2's balanced output gives double the voltage, so -3H is 6 V and +6H is 16.92 V RMS balanced. Head-Fi, Apr 2019
• 2019-04-14Watts says whether balanced or RCA is better into active speakers depends on the equipment, and advises trying both. Head-Fi, Apr 2019
• 2019-04-21Watts says pin 1 of TT2's XLR must connect to pin 1 on the amp, or large common-mode differences could damage the amp. Head-Fi, Apr 2019
• 2019-04-23Watts says TT2's low gain mode has lower residual noise, but the difference is inaudible through a power amp. Head-Fi, Apr 2019
• 2019-05-16Watts says a reviewer's hi-res dropouts came from an optical plug not fully clicked in, plastic fibers over 0.25 m may fail at 192 kHz, and rate changes cannot damage TT2. 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
• 2019-06-01Watts 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
• 2019-06-08Watts says TT2's RCA and XLR outputs can feed two systems at once, with probably negligible effect, and suggests checking by unplugging one. Head-Fi, Jun 2019
• 2019-06-10Watts says TT2 supplies the same current in both gain modes for the same voltage and load, but low gain is limited to about 3 V RMS, 1.5 A into 2 ohms. Head-Fi, Jun 2019
• 2019-06-11Watts says TT2 follows the same analog philosophy as his other DACs: one global feedback linear amplifier with two resistors and two capacitors in the signal path. Head-Fi, Jun 2019
• 2019-06-14Watts says TT2 can output 10 A in SPICE modeling for short bursts, but peak current is meaningless; current linearity, with distortion stable into low loads, matters. Head-Fi, Jun 2019
• 2019-06-28Watts says TT2 typically draws 13 W as a DAC and the Hugo M Scaler 12 W when working. Head-Fi, Jun 2019
• 2019-06-29Watts says it is due to PSU leakage, entirely safe, and removable by grounding a BNC input or the single BNC output ground; TT2 behaves the same. needs context Head-Fi, Jun 2019
• 2019-07-03Watts says TT2's negative output uses the same output stage design as the positive or SE outputs, so the 5 A peak applies to both. Head-Fi, Jul 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
• 2019-07-19Watts says TT2 worked fine in Indonesia, even once on 310 V RMS mains, sounding the same as in the UK. Head-Fi, Jul 2019
• 2019-08-05Watts says TT2's SE outputs dissipate fine driving his B&W 803 D3 at +6 dB or +12 dB, but balanced quadruples internal loss, risking thermal trips at 8 ohms or less. Head-Fi, Aug 2019
• 2019-08-06Watts mocks upgrading the supply chain, saying TT2's real PSU is its internal inductor, supercap, RF filtering and regulation, and he hears no difference pulling the brick. Head-Fi, Aug 2019
• 2019-08-21Watts says IEM hum on TT2 is cured by earthing it, battery power, breaking the body path, or lower impedance IEM cables, as PSU leakage current causes ground voltage drops. Head-Fi, Aug 2019
• 2019-08-22Watts says setting a Pilot Pro 2 to 12 V limits peak output only above +7 dB, with no change in THD and noise, though tests of the filter show differences better. needs context Head-Fi, Aug 2019
• 2019-09-16Watts says a high-pitched noise from TT2 with the display on is not normal; it should be silent from 1 m. Head-Fi, Sep 2019
• 2019-10-03Watts explains clipping versus distortion rising with current, says TT2 avoids crossover distortion and current limiters, drives his 803 D3, and display noise is LED multiplexing. Head-Fi, Oct 2019
• 2019-10-09Watts says DAC mode is identical to amp mode at -5L, one amplifier does I-to-V, filtering and buffering, and gain changes mute 16 seconds while the DC servo settles. Head-Fi, Oct 2019
• 2019-10-10Watts says TT2's digital gain reaches +18 dB, low gain clips above 3.3 V RMS at -2 dB, and high gain allows 9.4 V RMS, safe to +6 dB. Head-Fi, Oct 2019
• 2019-10-16Watts says TT2 shuts down below about 11 V and errors above 15.5 V, the M Scaler accepts about 5 to 15.5 V, and linear PSUs degrade sound and void warranty. Head-Fi, Oct 2019
• 2019-10-22Watts says, traveling with Hugo 2 and M scaler instead of TT2, he can live without TT2 but not without the M scaler, which he calls essential. Head-Fi, Oct 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
• 2019-12-06Watts 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
• 2019-12-14Watts tells a TT2 owner every DAC upsamples, the M scaler matches sinc to 16 bits for accurate transients, blind tests are insensitive, and he uses Aeon Closed on planes. Head-Fi, Dec 2019
• 2019-12-30Watts uses the stock Aeon 2 cable, cannot discuss future products, and says TT2 sounds and measures the same on stock PSU, a power bank, or with PSU disconnected. Head-Fi, Dec 2019
• 2019-12-31Watts corrects a poster's energy math: TT2's super caps store 375 Joules, its 60W PSU covers 7.3W into 8 ohms plus about 13W quiescent, with dynamic bursts from the caps. Head-Fi, Dec 2019
• 2020-01-02Watts says if TT2 would only serve as a DAC into an integrated amplifier, you would be better off with the M Scaler, though transparency would be the same. Passion for Sound 23:23
• 2020-01-02Watts says TT2 is more transparent than Qutest (better noise shapers, components, supply, output stage), but the M Scaler uniquely brings timbre, pitch, separation and musicality. Passion for Sound 23:33
• 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
• 2020-01-02Watts says 12v works with TT2, a 100W/h power bank gives over 7 hours driving headphones, warns about power-bank limits on flights, and suggests Hugo 2 for portability. 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
• 2020-01-20Watts explains isolating output-stage supply currents, shown in TT2's distortion plot, says delay follows tap length and oversampling, describes the M scaler's asymmetric video filter, and heard no USB-optical difference. Head-Fi, Jan 2020
• 2020-02-22Watts finds TT2 slightly warmer in high gain, says not to exceed -3L in low gain, to match volume numbers when comparing, and low gain is for IEMs. Head-Fi, Feb 2020
• 2020-02-22Watts says TT2's low gain only lowers residual noise, audible only with sensitive IEMs, and both modes measure nearly identically at -3 or lower. Head-Fi, Feb 2020
• 2020-02-24Watts says TT2's amp mode and headphone mode differ only in active connectors and remembered settings, so gain settings are identical. Head-Fi, Feb 2020
• 2020-02-24Watts says TT2's DAC mode equals amp mode at -3L, since DAC mode is fixed in low gain, and adds that darker is better. Head-Fi, Feb 2020
• 2020-02-24Watts corrects himself: TT2's DAC mode is 2.5 V, the knee of the low-gain distortion curve, as 3 V can be too hot for many pre-amps. Head-Fi, Feb 2020
• 2020-02-25Watts says the M Scaler and TT2 detect sample rate differently, and advises padding track changes with silence in JRiver or a re-sync delay in Roon. Head-Fi, Feb 2020
• 2020-04-01Watts says he chose TT2's SMPS as the only one matching a battery's measured HF performance; being ungrounded raises 2 GHz loop impedance, slightly helping the M scaler too. Head-Fi, Apr 2020
• 2020-04-06Watts says TT2 hum with sensitive IEMs comes from 100uA PSU leakage and is fixed by grounding via XLR pin 1, phono, BNC or DX grounds, not isolated USB. Head-Fi, Apr 2020
• 2020-04-11Watts says Hugo 2 is class A into 300 ohms, TT2 is biased an order higher with 30nS transistors, and TT2 shows no crossover or HF distortion at 12W. Head-Fi, Apr 2020
• 2020-04-12Watts says TT2 is Class A into 30 ohms, Class AB by 8 ohms, explains why bias matters despite the analog noise shaper, and tunes it for 4 ohms up. Head-Fi, Apr 2020
• 2020-04-15Watts has not heard the M Scaler with the original Hugo TT, which would need one BNC as it is 384k max, and suggests trying TT2 with the M Scaler. 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
• 2020-05-04Watts says a TT2 rebooting at start-up likely has a PSU failing the 3A draw; return to the dealer, try another PSU, else suspect a regulator fault. Head-Fi, May 2020
• 2020-05-06Watts says he has no wideband FFT plot of TT2 as requested, but recalls Jude publishing TT2 out-of-band noise on the measurement thread. Head-Fi, May 2020
• 2020-05-07Watts says a car battery is the best PSU but a power bank suffices, TT2 gains nothing, and a battery helps the M scaler by removing 2GHz ground return currents. Head-Fi, May 2020
• 2020-05-25Watts says 13.2V works with M scaler and TT2 on separate supplies, TT2 is supply-insensitive, and a battery on the M scaler removes the ground loop into the DAC. Head-Fi, May 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
• 2020-06-05Watts says the tingle is a safe 100 uA PSU leakage depending on local mains wiring, and grounding the chassis or a BNC input, away from the DAC, cures it. Head-Fi, Jun 2020
• 2020-06-24Watts says TT2's USB isolation rules out a USB ground loop, ferrites handle 2 pF coupling at 2 GHz, and IEM hum is PSU leakage fixed by grounding TT2. Head-Fi, Jun 2020
• 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 an inner amplifier linearizes the output stage inside one global feedback loop; TT2 plots show no distortion above 3 kHz for 20 Hz, 12 watts into 8 ohms. Part-Time Audiophile 20:05
• 2020-07-04Watts says linear PSUs do change TT2's sound but worse, adding hum and RF noise that sounds brighter, and notes TT2 sounds and measures the same with the PSU disconnected. Head-Fi, Jul 2020
• 2020-07-06Watts says linear PSUs add mains hum, vibration, magnetic fields and coupling; TT2's chosen SMPS showed no noise degradation in a 96kHz bandwidth, is unearthed, and matched a battery. Head-Fi, Jul 2020
• 2020-07-07Watts says TT2's real PSU is internal (inductor, supercaps, RF filters), recommends XLR pins 1 and 2 for speakers, and warns some subs short pins 1 and 3. Head-Fi, Jul 2020
• 2020-07-15Watts says a poster's TT2 clicking issue is a mystery; Chord reports none of the thousands of TT2s returned with clicks, so it may be a bug. Head-Fi, Jul 2020
• 2020-07-23Watts says TT2 is not Class D, which would destroy transient timing; its single amplifier has one global feedback path, a second-order analog noise shaper and fast discrete transistors. Head-Fi, Jul 2020
• 2020-07-27Watts says TT2 can stay on 24/7, DAC mode equals low gain at -5L, and an external amp often sounds warmer from distortion and capacitor dielectric absorption. Head-Fi, Jul 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
• 2020-07-28Watts gives TT2 levels (-5L is 2.4V RMS, 0H 4.2V), calculates supercap life at 500,000 hours, and says leaving it on aids reliability. Head-Fi, Jul 2020
• 2020-07-29Watts advises staying single-ended for the Abyss TC on TT2; -20H is low, up to +6H is possible, but that would reach a hearing-damaging 121dB SPL. Head-Fi, Jul 2020
• 2020-08-10Watts says 2 m BNC cables beat 1 m, solid-core 2 GHz ferrites help most, clip-on ferrites hurt with the M Scaler, and battery power breaks its ground loop. Head-Fi, Aug 2020
• 2020-08-16Watts says analog cables matter so he makes his own, and active balanced headphone outputs degrade transparency with no benefit given TT2's 9.3 V RMS and 5 A single-ended drive. Head-Fi, Aug 2020
• 2020-09-07Watts advises running the M Scaler from the 12 V battery and not worrying about TT2, since breaking the current path once suffices; keep the battery isolated from ground. Head-Fi, Sep 2020
• 2020-09-08Watts says battery isolation works if capacitance to ground is low, as with his PowerAdd bank; power-up order causes no damage, but TT2 should be last on, first off. Head-Fi, Sep 2020
• 2020-09-30Watts says a linear supply will make no difference or degrade TT2's sound, and will invalidate the warranty. Head-Fi, Sep 2020
• 2020-09-30Watts says overvoltage damage from out-of-spec PSUs voids warranty cover, many audiophile PSUs are unregulated, and the supplied TT2 and M Scaler PSU measured as quiet as a battery. Head-Fi, Sep 2020
• 2020-10-10Watts sees no point in USB clocks since TT2's isolation follows the USB decoder, says added source devices raise RF noise, and lists laptops and a phone as his sources. 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
• 2020-11-23Watts 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
• 2020-11-27Watts says TT2's unearthed PSU was chosen for the best measurements and battery-like sound; full isolation attenuates ground loop currents, at the cost of a 100uA leakage tingle. Head-Fi, Nov 2020
• 2020-11-28Watts says a TT2 that only starts on a 12V battery likely has a poor inrush limiter tripping the PSU; get it replaced, though running from 12V battery is fine. Head-Fi, Nov 2020
• 2020-12-27Watts says adding the M Scaler would be a bigger jump in separation, speed, warmth and flow, while TT2 is more refined than Hugo 2, and suggests trying both. Head-Fi, Dec 2020
• 2021-01-08Watts says TT2 drives efficient speakers single-ended, but XLRs thermally trip into 8 ohms or less; 16 ohms is fine, and amps shorting pins 1 and 3 risk damage. Head-Fi, Jan 2021
• 2021-01-08Watts says active ATC speakers on TT2's XLRs are fine if the input is truly balanced, as pro gear will not short balanced outputs. Head-Fi, Jan 2021
• 2021-01-09Watts confirms the XLR wiring and says TT2 XLR gives the Abyss 7W per channel (126 dB SPL) and single-ended 1.8W (120 dB), so stay single-ended. Head-Fi, Jan 2021
• 2021-01-20Watts says balanced adds amplifiers that cost transparency, so his DACs are single-ended; halving gain halves noise for IEMs; linear PSUs add RF and noise floor modulation. Head-Fi, Jan 2021
• 2021-01-20Watts says balanced always costs a little transparency from an extra stage; headphones see only the voltage difference, while with power amps balanced can sometimes sound better. Head-Fi, Jan 2021
• 2021-01-20Watts says XLR pin 2 equals the RCA signal, the outputs handle over 5A RMS, single-ended drives the Abyss 1266 to 120dB, and balanced comparisons must be volume matched. Head-Fi, Jan 2021
• 2021-01-20Watts doubts the TT2 has a permanent channel imbalance since Chord QA measures units, cannot think of a mechanism, and suggests checking headphone cables. Head-Fi, Jan 2021
• 2021-01-23Watts says reducing NFM and timing errors correlates with musical involvement, warns impressive sound can mislead listening tests, and notes he missed TT2's small DAC-mode loss before production. Head-Fi, Jan 2021
• 2021-01-31Watts says an extra stage degrades transparency, so he won't design a headphone amp; for more power choose TT2, as more Hugo 2 power needs batteries or a charge pump. Head-Fi, Jan 2021
• 2021-03-05Watts explains TT2 draws only DC from the brick because a large inductor isolates the supercaps, keeping audio currents and PSRR distortion out; big toroids are not inherently better. Head-Fi, Mar 2021
• 2021-03-06Watts says he cannot imagine any mechanism by which a faulty stock PSU would cause channel imbalance in TT2. Head-Fi, Mar 2021
• 2021-03-20Watts says an optical-only DAC has about 0.1pF to ground, while HMS to TT2 has about 2pF through the BNC isolators, fixed by battery-feeding HMS or solid-core 2GHz ferrites. Head-Fi, Mar 2021
• 2021-03-25Watts says TT2's XLR used single-ended into a high-impedance input is fine, but some XLR inputs short pins 1 and 3; avoid balanced loads at or below 10 ohms. 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
• 2021-03-31Watts says CD player differences may be RF pickup via power amps, 2GHz ferrites or cutting loops fix M scaler to TT2 noise, notes a migraine; ADC work continues. Head-Fi, Mar 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
• 2021-04-20Watts says TT2 easily drives two headphones at once, and that two units share the same algorithm and crossfeed code, so a sound difference has another cause. needs context 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
• 2021-05-18Watts 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
• 2021-06-04Watts 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
• 2021-06-22Replying that NOS, R2R and ESS DACs have caught up with TT2, Watts says his digital modules exceed 64-bit float, reproduce -301dB, with fixed-point noise-shaped noise below -400dB. Head-Fi, Jun 2021
• 2021-06-26Watts says a linear PSU only degrades or matches TT2's stock unit, since random mains RF raises noise floor modulation and brightness, and regrets not adding more RF filtering. Head-Fi, Jun 2021
• 2021-07-18Watts says TT2 is warmer in tonal balance than Hugo 2, so he takes TT2 to hotels, but Hugo 2 remains his choice on aircraft. Head-Fi, Jul 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
• 2021-08-03Watts says his TT2 ran a week on 316V mains in Bali, explains semiconductor failure causes, and leaves equipment under 20W on, citing failures only at turn-on. Head-Fi, Aug 2021
• 2021-08-04Watts says TT2 draws a steady 12 to 13W, its standby is fine, and the M scaler keeps one LED on in low power mode, dimmable via both DX buttons. Head-Fi, Aug 2021
• 2021-08-11Watts says TT2's coax receiver stays powered in standby, so sharing a coax source with another DAC is no problem. Head-Fi, Aug 2021
• 2021-08-17Watts says 4 ohm speakers on TT2 single-ended are fine, as it suits loads like his 3 ohm B&W 803 D3, giving at most 95 dB SPL at 1m. Head-Fi, Aug 2021
• 2021-08-26Watts says TT2 in high or low gain has no significant DC output thanks to the digital DC servo, so it is safe with a DC-coupled power amp. Head-Fi, Aug 2021
• 2021-09-11Watts says TT2 at +0H gives about 2.25W into 8 ohms, +7H 7W; CDs clip above +7H, but sources with 6dB margin allow +12H, even +18H on his 803D3s. Head-Fi, Sep 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
• 2021-11-24Watts says room setup gets quick with experience, he uses TT2 single-ended, and errors at -300dB are audible even single blind, explaining why cables measure identically but sound different. Head-Fi, Nov 2021
• 2021-11-30Watts lists his flight and hotel kit, says measurements catch gross flaws, and that the brain compensates for transducer distortion but not digital errors like NFM and timing errors. Head-Fi, Nov 2021
• 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
• 2022-02-09Watts 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
• 2022-02-11Watts says his high-end M Scaler uses a Choral (DAVE) chassis and is not 4M taps, algorithm outweighs taps, and gives SINAD of 125dB (Mojo 2) and 127dB (TT2). Head-Fi, Feb 2022
• 2022-02-17Watts says TT2 should not use balanced outputs into speakers or loads under 16 ohms as it will thermally trip; single-ended drives his B&W 803 D3 loud enough. Head-Fi, Feb 2022
• 2022-02-26Watts says a working powered speaker will not damage TT2, but its ground connection could carry RF currents that brighten headphone listening, so try switching it on and off. Head-Fi, Feb 2022
• 2022-03-03Watts says he bought a Stealth unheard with positive first impressions, now sees M Scalers feeding DACs for headphones and DX amps for speakers, and TT2 suffices for his speakers. Head-Fi, Mar 2022
• 2022-03-08Watts describes his first orchestra recording with a ribbon mic into a Focusrite Scarlett, matching live volume on Hugo 2 and Stealth at blue, and TT2 driving his 803 D3s. 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 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 says he would run Susvara from TT2 single-ended (95dB SPL; XLR gives 101 dB), warns over 80dB long-term damages hearing, and would never add a headphone amp. Head-Fi, Mar 2022
• 2022-03-31Watts says 32-bit integer reaches TT2's FPGA but 32-bit float is unsupported; he runs TT2 at +7 via M scaler, and Utopia needs high gain, low gain suiting IEMs. Head-Fi, Mar 2022
• 2022-04-08Watts says headphones can be swapped on TT2 only when silent, since unplugging during music risks momentary shorts, advice that applies to all DACs. Head-Fi, Apr 2022
• 2022-04-09Watts advises low gain for sensitive IEMs, explains how power splits between two headphones by impedance, says unplug only when silent, and has asked Chord about the handbooks. Head-Fi, Apr 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
• 2022-04-10Watts says the desktop DAC headphone relay protects on plug-in via a delay, but unplugging can short before relays act; Mojo 2 and Hugo 2 outputs are always active. Head-Fi, Apr 2022
• 2022-04-12Watts gives the XLR pin standard, says speakers should use the single-ended connection, and warns that pin 3 shorted to pin 1, as some amp inputs do, may damage TT2. Head-Fi, Apr 2022
• 2022-04-12Watts says TT2 will thermally shut down driving 8 ohm loads or less in balanced mode, and anyone not seeing shutdowns does not need the extra power. 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
• 2022-04-25Watts says TT2 and M Scaler can be stacked, but are better apart with Wave or solid-ferrite BNC cables; use high gain unless IEMs hiss; avoid wireless subwoofer links. Head-Fi, Apr 2022
• 2022-04-25Watts says TT2 need only be separated if it thermally shuts down, explains how Blumlein encodes lateral and depth information, and says conventional SRC has severe sound-quality problems. Head-Fi, Apr 2022
• 2022-04-26Watts advises high gain into a power amp, keeping units on Wave cables apart to avoid capacitive coupling and cable ends touching, and says TT2 tolerates running warm continuously. Head-Fi, Apr 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
• 2022-05-28Watts says a TT2 over-temperature (OT) error is most likely a shorted headphone cable or plug; if it recurs with nothing connected, the TT2 has a problem. 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
• 2022-06-22Watts says Hugo 2's charger is a simple generic unit, while for Hugo TT2 he spent much time on PSU selection so supercap listening sounds unchanged. 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
• 2022-07-02Watts clarifies he meant not to drive speakers from TT2's balanced XLR output; using XLR pins 1 and 2 to drive speakers is fine. Head-Fi, Jul 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
• 2022-07-19Watts says TT2 has no line output: single-ended is volume-adjusted from 0 to 9V RMS and XLR doubles that to 18V, so a sub can be fed from either. Head-Fi, Jul 2022
• 2022-07-19Watts says a sub's line-level and speaker-level inputs both feed its power amp, an easy load for TT2, and guesses speaker level is best since less attenuation is the goal. Head-Fi, Jul 2022
• 2022-07-21Watts says non-supplied PSUs void Chord's warranty, linear supplies lack 100 kHz to 10 GHz RF filtering, and transient timing reconstruction differs from transient response, which only listening tests reveal. Head-Fi, Jul 2022
• 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
• 2022-08-25Watts says claiming no impulse-response difference while noting TT2's sharp filter is contradictory, since impulse and frequency responses are FFT equivalents and a sharp filter needs a long impulse response. Head-Fi, Aug 2022
• 2022-08-26Watts explains TT2's balanced output (gain 5 and -1 amps), says single-ended is more transparent owing to fewer feedback parts, shows measurements, and says the pulse array is his IP. Head-Fi, Aug 2022
• 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
• 2022-09-07Watts confirms TT2 needs 5V on the USB cable because its galvanic isolator is powered from the USB +5V. 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 the lovely thing about the TT2 is its volume control knob. The Source AV 9:00
• 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
• 2022-10-03Watts says USB sounding different from optical on TT2 is RF noise through the isolator's 2pF coupling, causing brightness, and a £9.29 5m plastic optical cable equals his glass one. Head-Fi, Oct 2022
• 2023-01-03Watts says TT2's XLR outputs trip thermally into 8 ohm speakers, leaving the 7W single-ended outputs, and Hugo 2's second-order noise-shaper amp eliminates crossover distortion. Head-Fi, Jan 2023
• 2023-01-11Watts says the fault lies with the amp, whose XLR input shorts the negative leg to ground; he advises using RCA instead, since the short can damage TT2. Head-Fi, Jan 2023
• 2023-02-04Watts says TT2 gives 7 watts into 8 ohms; DX outputs are for future 100 to 400 watt DACs driving speakers directly, a program that has stalled. Dusty Audio 1:01:31
• 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 Qutest's supplied unit equals a 12-volt car battery, so linear supplies that sound different degrade it; TT2 runs ten seconds on supercaps with the supply unplugged. Soundnews 40:35
• 2023-02-05Watts says the difference is tiny; of many TT2 supplies measured at 100 kHz bandwidth all degraded performance except one, at half a dB, which sounded like a car battery. Soundnews 41:34
• 2023-02-05Watts says people complain that TT2 comes with a cheap power supply. Soundnews 42:27
• 2023-02-05Watts says he cares only about actual performance; TT2's supply is as good as a car battery, so a linear supply's audible difference on TT2 is to him a degradation. Soundnews 42:43
• 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
• 2023-03-01Watts 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
• 2023-03-12Watts says some amps are overloaded by a 3V input, raising distortion and sounding harder without clipping, which is why Qutest has three output voltage settings. 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
• 2023-03-26Watts says Qutest and TT2 sound the same on a car battery as on the supplied switch mode supply, except TT2 with an M Scaler; better supplies would add RF. Eric's Hi-Fi 19:18
• 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 TT2 has supercaps and RF filters, but the supercaps do not help with RF noise. Eric's Hi-Fi 20:47
• 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 his output amp, a second-order analog noise shaper, removes high-frequency and crossover distortion; loading a TT2 from 300 to 8 ohms at 9 volts changes only second harmonic. The Headphone Show 50:19
• 2023-03-28Watts says his loudspeakers are B&W 803s, driven directly from his TT2's 7 W output. The Headphone Show 57:24
• 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
• 2023-05-27Watts says reducing RF noise lowers perceived volume by one or two dB, since noise floor modulation sounds brighter, and is convinced a linear supply on TT2 adds RF noise. Head-Fi, May 2023
• 2023-06-01Watts says a PowerAdd power bank and the supplied SMPS sounded and measured the same in the audio band, while other SMPS tested for TT2 measured poorly at high bandwidth. Head-Fi, Jun 2023
• 2023-06-18Watts says an isolated power bank or Wave cables break the M Scaler's GHz ground loop, longer standard BNC sounds better via common mode inductance, and Krisdonia sounded worse. Head-Fi, Jun 2023
• 2023-06-18Watts says TT2 is fine on its supplied PSU, a power bank made no difference, and earthing is largely irrelevant at RF once mains connects everything via transformer winding capacitance. Head-Fi, Jun 2023
• 2023-09-29Watts says 7W from TT2 should not damage speakers unless clipping, and a stereo ADC in design will offer SRC-based external word clock sync and possibly Dante. Head-Fi, Sep 2023
• 2023-10-01Watts says he drives directly with TT2s and the Stealths, following his answer that he uses B&W 803 D3s. The Source AV 39:47
• 2023-12-22Watts says that traveling with TT2 and Hugo M Scaler, he stacked or separated them by hotel layout and never noticed a sound-quality difference. Head-Fi, Dec 2023
• 2023-12-24Watts names his upcoming projects as the M scaler to match DAVE and the Ultima DAC, and says certainly not TT3. Head-Fi, Dec 2023
• 2024-02-12Watts says running TT2 into a short can damage it, as it can deliver 4A, and driving amps and subwoofers together is safe as long as TT2's output is never shorted. Head-Fi, Feb 2024
• 2024-02-22Watts says galvanic isolation fails at GHz via capacitance, optical breaks the link, and an LPS on TT2 would be a downgrade that sounds etched due to no RF filtering. Head-Fi, Feb 2024
• 2024-06-25Watts says iFi's 1uV PSU noise figure is meaningless without FFT bandwidth, implying 141 uV broadband; TT2's noise floor is 9nV and Chord's Li-ion batteries measure below the APx555. Head-Fi, Jun 2024
• 2024-06-30Watts says faint music heard from TT2 with XLR cables suggests an amp input shorting pins 1 and 3; the large currents probably make a PSU inductor noisy. Head-Fi, Jun 2024
• 2024-10-02Watts says he uses a scaler with TT2 on his main loudspeaker system and travels with Quartet paired with Hugo 2 in hotels, and that all are elevated in performance. Head-Fi, Oct 2024
• 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
• 2024-10-06Watts says the best pre-amp or power amp is none, cites TT2 sounding the same into an 8 ohm load, and says the large-power DX DAC concept is not dead. Head-Fi, Oct 2024
• 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
• 2025-01-13Watts lists the reference supply, pulse array flip-flops, gain stage and output stage as distortion sources, and says a 20Hz 12W TT2 test shows crossover distortion eliminated. Head-Fi, Jan 2025
• 2025-02-10Watts says to use TT2 filter 1 or 2 (he uses 2) with the Hugo M Scaler, not 3 or 4. Head-Fi, Feb 2025
• 2025-02-25Watts warns that a 0.29 ohm load may damage TT2 before protection acts, and any nominal load under 4 ohms is a no-no. Head-Fi, Feb 2025
• 2025-03-27Watts says TT2's low-gain resistor and relay sit in parallel with the feedback resistor, because series contacts and solder joints degrade depth, detail and transparency while parallel ones do not. Head-Fi, Mar 2025
• 2025-03-27Watts says TT2's balanced outputs should not drive 8 ohm speakers, as above 7W it thermally trips; balanced is for low-sensitivity 32 ohm headphones or balanced amp inputs. Head-Fi, Mar 2025
• 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

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