M Scaler and Quartet settings and operation

Upscaling and the M Scalers

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Everything he said on this topic (41)

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2017-01-08Watts says the M scaler outputs any multiple of the input rate, benefiting DAVE most through its 256FS and 2048FS filtering; other DACs improve by an amount he cannot say. Head-Fi, Jan 2017
2017-01-08Watts says the taps are used only when upscaling, so a 768 kHz signal would pass through another M scaler unchanged, and that Moore's law is running out of steam. Head-Fi, Jan 2017
2017-05-08Watts says the M scaler is 0.234 dB louder (-2.766 dB insertion loss, +3 dB volume) and its 10 A signal-dependent FPGA ground current forces a separate, isolated box. Head-Fi, May 2017
2017-05-16Watts notes the M scaler's 2.76 dB insertion loss and says 0.5M versus 1M taps, or video mode, changes depth greatly, hypothesizing coefficient truncation over reverb-length periods. Head-Fi, May 2017
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
2018-07-21Watts says the M Scaler's million-tap WTA core is identical to Blu's, lists isolated USB, BNC and optical inputs and dual BNC, BNC and optical outputs, adjustable rate and pass-through. c w 23:19
2018-07-21Watts says gain is unchanged for listening tests; the filter's 1.3 seconds of music means 0.63 s delay, so video mode uses an asymmetric filter with 100 ms delay. c w 24:08
2018-07-21Watts describes auto video mode on 48 kHz input, automatic source switching when USB is silent, remote control, and a DX mode for DX power amplifiers still under development. c w 24:49
2018-07-21Watts says selecting 384 kHz halves the taps output; 768 kHz gives 1.3 uS resolution, while 1536 would halve the data window to 0.63 seconds; 768 is the listening-test optimum. Head-Fi, Jul 2018
2018-09-05Watts explains the Hugo M scaler OP SR colors (red pass through, green 176.4/192, blue 352.8/384, white 705.6/768 1M taps); only white enables dual data mode. Head-Fi, Sep 2018
2018-09-21Watts says something needs the Davina project, which he is working on, and pass-through mode has the same 2.75 dB loss, making AB testing easy. Head-Fi, Sep 2018
2018-09-23Watts says the behavior is correct, dual BNC operation works only on white, and he will get the manual corrected. 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
2018-11-02Watts says it matches Blu 2 with 3 dB headroom, pass-through is volume matched, the main change is musical and takes time, and the supplied SMPSU is fine. 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
2018-11-05Watts says the OP SR light always stays on, even in auto shutdown. Head-Fi, Nov 2018
2018-11-14Watts says he has never used Krell, and that M Scaler pass-through follows the input rate, so 44.1 kHz playback turns Hugo 2's indicator red. Head-Fi, Nov 2018
2018-12-07Watts says the 4x (48 to 192 kHz) filter uses exactly a quarter of the 16x coefficients, not a decimation, and is volume adjusted with near-Gaussian 24-bit dither. Head-Fi, Dec 2018
2018-12-07Watts says MC 21, 22 and 24 on USB never gave him issues, lower output rates are not down conversions, and pass-through is not bit perfect due to attenuation compensation. Head-Fi, Dec 2018
2018-12-07Watts says in pass-through the WTA filter becomes a one-tap filter, while the SRAM stays identical so group delay is unchanged. Head-Fi, Dec 2018
2018-12-13Watts lists Hugo M Scaler features (pass-through, video and auto modes, remote, DX), says it runs from 9 to 15 volts, and that he uses it with a battery on flights. Pursuit Perfect System 14:11
2018-12-28Watts says white is dual data mode, two mono signals at 352/384; Hugo 1 cannot accept it and treats one mono signal as stereo, so use single BNC instead. Head-Fi, Dec 2018
2019-01-15Watts says no, because pass-through does not change the sample rate. needs context Head-Fi, Jan 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
2019-03-25Watts says 768k works fine on the M scaler, and an M-scaled Red Book file sounds like a native 768k recording, unlike native 384k recordings. Head-Fi, Mar 2019
2019-03-26Watts says the M scaler passes 768k through, 768k sounds special against 384k, and 352.8/384k recordings he has heard sound little better than 44.1. Head-Fi, Mar 2019
2019-05-21Watts says pass-through keeps the same delay with the filter disabled, the M scaler's impact varies by listener, and lasting musical enjoyment matters more than transparency gains. Head-Fi, May 2019
2019-08-10Watts says that in pass-through only one BNC cable is active, so the owner must connect the right cable or select the appropriate coax input. Head-Fi, Aug 2019
2019-10-18Watts says pass-through is not bit perfect; it carries the M scaler's 2.76 dB insertion loss, so DAVE direct must be turned down 3 dB for comparison. Head-Fi, Oct 2019
2019-10-23Watts says the M scaler enters low power mode, not off, after ten minutes of digital silence, shown by the lone OP SR LED; pressing both DX buttons dims it. Head-Fi, Oct 2019
2020-04-11Watts says video mode is set to 104 mS, the longest delay usable with TV frame interpolation, and the delay stays fixed in pass-through in case video is playing. Head-Fi, Apr 2020
2020-06-04Watts says TT2 matches Mojo and DAVE: -3dB is 3V RMS and four remote clicks down gives 1.89V RMS; with an M scaler set -4, as it attenuates 2.75 dB. Head-Fi, Jun 2020
2021-04-20Watts says the scaler will treat a given input as pass-through, merely attenuating it by 2.76 dB to keep volume levels consistent. needs context Head-Fi, Apr 2021
2021-05-10Watts says the M scaler exposes recording defects by being more transparent, and inter-sample clipping is handled by a -2.76dB gain reduction on all outputs, including pass-through. Head-Fi, May 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
2021-12-11Watts says 705/768 files are handled like pass-through: volume-scaled to match other inputs, then aggressively noise shaped to 24 bits for the BNC outputs, so 32-bit inputs convert transparently. Head-Fi, Dec 2021
2022-07-06Watts says the Hugo M Scaler's extra noise at 2x and 4x is deliberate Gaussian dither that sounds better, 16x noise is unchanged, and Chord DACs remove its jitter. Head-Fi, Jul 2022
2022-08-19Watts says the intent was Chord DACs; the 96 and 192 kHz outputs were mainly for recording, e.g. 44.1 run at 'one seven four kilohertz', though universality helps. AVstore 25:51
2024-03-18Watts says Quartet's single BNC and optical outputs are fixed at 176.4/192k, decimated from 705.6/768 kHz with new filters and separately noise shaped for 4FS. Head-Fi, Mar 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
2026-03-17Watts says the Hugo M Scaler's 192 kHz outputs feed any DAC, but the real benefit comes only at 768 kHz, an important rate whose technical reasons he leaves aside. ecoustics 25:10