50 ms delay on all Bluesound speakers. So a Soundbar?

Took delivery today of a Pulse Soundbar 2i. Very lovely except it has the standard 50ms delay that all Bluesound products have (in order for multi-room sync to work apparently). And that makes lip-sync a real issue. There is a lip sync delay slider in the preferences but this starts at 50ms and goes up to 150ms. I don’t understand that. The problem is I need to get below 50ms and of course it’s not possible. Ideally the thoughput should be a few miiliseconds and then the brain would do the rest.

I think some people are more sensitive than others to lip-sync, but for me as soon as I switch back to a regular analog speaker I stop feeling sea sick. It’s like night and day.

I’m posting here because there is a lot of furore over on the Bluesound forum about this and Bluesound are being defensive, saying they will look into it.

Can’t you additionally adjust lip sync in your TV’s settings to have it delay the video?

Well that’s a good point!
I think not on my TV unfortunately but I am interested if others have TV’s that can do that because that would defintely solve this issue.

I thought that lip-sync on TVs (and AV amps) only delays the audio? This is because it is the video processing that takes longer, so sound will usually be ahead of video unless delayed to sync with the video.

… you may well be right and my memory failing me …
… but thought I did just that some years ago on my Samsung TV since feeding it’s optical out and running convolution prior to D/A resulted in audio lagging behind …

Yes it is the audio that gets delayed but if the minimum is 50ms it omits 0ms to 49ms which is where the need is.
I’m not sure what you say about different processing times is the case at the end of the chain…if you listen to the TV speakers or the analogue out, it’s in sync. Granted that might be due to some internal audio delay processing inside the TV. But the HDMI out going to Bluesound clearly needs a delay less than 50ms.

LG TV’s allow both + and - adjustments. Not all TV makers do.

Yes, wouldn’t surprise me. My TV and AV kit is over 4 years old (Sony & Arcam) . TV could easily push the audio out early, allowing a longer delay adjustment if necessary. Wasn’t the last but one HDMI spec supposed to sort out lip-sync issues? If it works as reliably as ARC control does then I wouldn’t trust it personally.

Not that easy, as it means holding video back (lots of memory - especially a problem for 4K).

The -ve audio delay adjustment is much less than +ve adjustment for that reason.

Ha exactly my experience too.

50ms is roughly 50ft or 15m in distance at a speed of sound c.340m/s.

Why on earth would you bring a soundbar to market with a 50ft delay?

Yup LG has the best solution.
I am amazed this is not standard but as you say, delaying video is a lot more cpu intensive than audio.

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