How much delay do the long filters add, and how do I keep lip sync with video?

Practical answer. He described two fixes for the Hugo M Scaler's 0.63 to 0.66 seconds at 48 kHz Head-Fi, Mar 2018Head-Fi, Dec 2018Head-Fi, Apr 2020: video mode, 104 mS at some cost in sound quality, with the source's audio delay set to zero Head-Fi, Aug 2018Head-Fi, May 2022Head-Fi, Jul 2018; or the full filter with the picture delayed to match, which he uses himself, now via an Nvidia Shield Head-Fi, Jan 2022Head-Fi, Jul 2022.

Route 1, video mode. He described one for the M Scaler and Blu Mk2 Head-Fi, Mar 2018Head-Fi, Aug 2017, and in 2015 a lower-delay setting for Dave Head-Fi, Jun 2015.

• He chose 104 mS deliberately: "I have gone for the max delay you can get away with without significant lip sync issues" (August 2018) Head-Fi, Aug 2018. In April 2020 he tied it to "using frame interpolation on your TV/projector" Head-Fi, Apr 2020.
• On setting audio delay to 0 (July 2018): "The brain can cope with a tiny audio delay, but has problems when audio is before the video" Head-Fi, Jul 2018.
• In July 2018 he listed the M Scaler's choices: video mode off (1M taps, 0.63 S delay), on (2/3M taps, 0.1 S delay), or auto, where a 48 kHz input is assumed to be video Head-Fi, Jul 2018. He said auto's convenience when watching YouTube wins it for him Head-Fi, Jul 2018.
• The Blu Mk2's low latency option cut delay from 630 mS to 104 mS (August 2017) Head-Fi, Aug 2017.
• The cost: he said video mode "does sound worse than the full 1M taps" (March 2018) Head-Fi, Mar 2018, and in May 2022 that asymmetric windowing gives lower latency "at a sound quality price" Head-Fi, May 2022. In November 2023 he added that in video mode the asymmetric form "sounded a lot better" than a symmetric one Head-Fi, Nov 2023.

Route 2, full filter with delayed video. Blu-ray: in a January 2017 post he said he had found over Christmas that JRiver could play ripped discs with a negative delay so the video is delayed, reporting -0.56 s for "perfect lip sync" Head-Fi, Jan 2017; he gave -0.63 s from August 2017 (repeated March and August 2018) Head-Fi, Aug 2017Head-Fi, Mar 2018Head-Fi, Aug 2018.

• Streaming: in April 2020 he found a standard Nvidia Shield can delay video; through an HDMI switch with optical outputs into the M scaler, Netflix and Amazon Prime "works perfectly" but BBC iPlayer "fails to lip sync" Head-Fi, Apr 2020. In January 2022 he said the delay can be up to 1 second Head-Fi, Jan 2022.
• In July 2022 he said his Shield's 0.63 second video delay lets the Hugo M Scaler work fully with the 1M taps Head-Fi, Jul 2022, and that because he cannot copy Blu-ray discs to his PC, streaming now gives him better sound Head-Fi, Jul 2022.
• Chord DACs and scalers take stereo PCM, so surround must be decoded and down-mixed first (July 2022) Head-Fi, Jul 2022.

Delay by product. Hugo: 34 mS at 48 kHz (June 2014); 38 mS in March 2015 Head-Fi, Jun 2014Head-Fi, Mar 2015.

• Hugo 2: a WTA filter latency of 34 mS with no sample rate named (July 2017) Head-Fi, Jul 2017; "about 31 mS for 48 kHz input" (April 2018) Head-Fi, Apr 2018; 16 mS at 96 kHz (July 2019) Head-Fi, Jul 2019. Since all displays delay video, he said more audio delay is probably needed Head-Fi, Apr 2018.
• Hugo TT2: 63 mS (October 2018); if the TV has frame interpolation, turn it on, as it adds video delay Head-Fi, Oct 2018.
• Dave: in March 2018 he said M Scaler video mode latency is "the same as Dave - 104 mS" Head-Fi, Mar 2018. In October 2017 he wrote that Dave's 164,000 taps is "about 0.2 seconds", pairing 1.4 seconds with 1M taps Head-Fi, Oct 2017. He did not reconcile the Dave figures.
• 1M-tap M scaler, October 2017 (before the Hugo M Scaler): at CanJam RMAF, asked about a million taps, he said "it's actually 0.63 seconds" and that it is "looking at 1.4 seconds worth of data or 0.7 seconds worth of latency", then that at 44.1 kHz the latency is about 0.7 seconds and at 48 kHz for Blu-ray it is 0.63 seconds miceblue425 57:05miceblue425 57:24.
• Hugo M Scaler: 0.71 s at 44.1 kHz and 0.65 s at 48 kHz (July 2018) Head-Fi, Jul 2018; 0.661 s at 48 kHz with video mode off, half that at 96 kHz and 0.165 s at 192 kHz (April 2020) Head-Fi, Apr 2020. The March 2018 post Head-Fi, Mar 2018 says "the M scaler", before the July 2018 launch; in August 2018 he said its core audio processing is identical to the Blu 2's Head-Fi, Aug 2018.
• Choral prototype: in July 2022 a prototype, "the Choral unit for Dave", had a mode using the full 1 second the Shield allows Head-Fi, Jul 2022; in October 2022 he said it would come on the "Choral x M scaler" Head-Fi, Oct 2022.
• Quartet M Scaler: in May 2025 he said the delay is "0.7 of a second with the M Scaler and it's three seconds with the Quartet M Scaler" Audiophile Junkie 17:12. In an interview published in October 2026 (recording date not stated; its transcript places it before May 2026), right after saying he watches movies with Quartet, he said "it's got one second delay mode on there" because the Shield can set video delay to one second HiFi Buys 2:14:45.

What he has not said. This archive has no delay figures for Qutest or the Mojo models, and nothing on Quartet's delay modes beyond that sentence. In November 2023 he wrote that "shorter latency will always degrade transient reconstruction" Head-Fi, Nov 2023.

Quotes

“It's why I go to the bother playing Blu-ray disks through JRiver and setting a negative 630 mS audio delay so I can use the full 1M taps.”2017-08-26 Head-Fi, Aug 2017

“I have gone for the max delay you can get away with without significant lip sync issues - it's 104mS.”2018-08-17 Head-Fi, Aug 2018

“The brain can cope with a tiny audio delay, but has problems when audio is before the video.”2018-07-24 Head-Fi, Jul 2018

“using the Nvidia Shield allows 1M taps properly played as video can be delayed by up to 1 second”2022-01-10 Head-Fi, Jan 2022

Dated positions

Caveats and open points

• Transcript figures (Quartet three seconds, the one second delay mode, the October 2017 figures of 0.63 and 0.7 seconds) come; check the recordings. The March 2018 M scaler figures (0.63 s, 104 mS) predate the Hugo M Scaler's July 2018 launch and name only "the M scaler".
• This archive gives no delay figures for Qutest or Mojo models and nothing on Quartet delay modes beyond one transcript sentence.
• His two Dave figures (about 0.2 s for 164,000 taps in October 2017; 104 mS in March 2018) are not reconciled by him in this archive.
• The one second delay mode sentence (interview published October 2026, recording date not stated) says "it"; the preceding sentence names Quartet.
• The Choral prototype scaler (2022) is reported under the name he used. In July 2023 he spoke of an M scaler "that will be in the Chord Choral range like Dave" Head-Fi, Jul 2023, and in September 2024, asked about Quartet, he called it "a Choral range product" The Source AV 17:15; no passage says in so many words that the prototype became Quartet.

Topics: Latency, video and surround