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17 years on and still no solution to AV Amp delays!

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As a reasonably techie guy I’ve been helping my neighbour set up his domestic sound system. He has a Sonos driven output in 5 separate rooms. There is a mixture of Sonos 5 speakers, Ports feeding AV amplifiers and an Amp running a pair of speakers. All the rooms are very separate acoustically apart from the lounge, which has a large opening into the kitchen/dinner area. The lounge has a Port feeding a good Sony AV surround sound amplifier and the kitchen has an Amp driving a pair of passive speakers. And so he is suffering from the dreaded ‘stadium echo’ effect when playing music in both the kitchen and lounge. The mechanism is easy to understand; the Sonos kit is all synchronised together but the Sony AV system adds its own delays after the output from the Sonos Port. Because the Sony amp, along with many other AV systems, is designed such that the video output is always lip synced with the TV picture, changing from surround to direct modes does not affect the audio delay. So it is impossible to reduce the Sony Amp audio processing delay to zero to ‘solve’ the problem.

I’ve spent quite some time looking back through the Sonos Community blogs. The earliest reference I’ve found so far to the AV Amp delay problem was 17 years ago

There are many, many other threads along the same topic. The root cause of the problem is well understood and explained but there is always an excuse why a fix can’t be offered. Yes, it would be difficult to implement variable delays that would allow any combination of Sonos and AV amps to work together. But, from the blogs, for most installations you only need to delay a single Sonos output device relative to the one feeding the AV receiver. Following the 80:20 rule that would fix the problem for most people.
Technically it is possible. There might be RAM constraints to how much delay can be introduced. But RAM is cheap. So I do not understand why Sonos is still not offering even a partial fix :-(

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melvimbe

But the source is stereo? Surely you want to reproduce the original sound, and don’t want to mess with it to create a ‘synthetic’ surround sound?

The delay is introduced by the AVR to deliver these effects, and I don’t think the delay is large enough to create lip sync issues by toggling the stereo button.

The source of audio to the AVR in this case is the Port, not TV. There are no lips to sync with.

To the quoted part, I suspect that even with a stereo source, and using the AVR dsp, the centre channel would still work, and if so, deliver the great benefit of controlling dialogue levels precisely when needed. Of course, the cost of that would be losing sync with Sonos.

One has to choose between these effects and perfect Sonos sync. I don’t see that ever changing.

I suppose their could be dialogue, such as podcast or what not streaming through the Port and Sonos network in general, but I really don’t think there would be a need to activate the center channel for these stereo sources.

A surround sound processor operating in a mode such as Meridian’s Trifield put common L & R sounds through the centre speaker, leaving L or R specific sounds on their respective channels. Thus anything centre stage, usually a singer or speaker comes out only on the centre speaker. The effect of this is that vocals are much cleaner and it reduces the criticality of the stereo ‘sweet spot’. Both people sat on the sofa get good vocals! Basically it reduces the audio clutter produced by sending the same sounds to independent L & R speakers. Its why I prefer stereo music played through a surround sound system.

I get the idea, it’s just seems that a center channel for clear dialogue seems less important for stereo music than for TV watching.

Danny

K

Kumar

The source of audio to the AVR in this case is the Port, not TV. There are no lips to sync with.

Indeed, and a full on duh moment for me. I was lulled down a wrong lane by my use case where lip sync matters - I have a Connect receiving TV audio via line in, feeding a stereo amp connected to two quality speakers and a sub in my patio. And for parties, the sound can be piped around the house to other Sonos units as well, in perfect sync including lip-sync with both TV video and streamed or NAS music from Connect as a source. All that is needed for this to work flawlessly is for all Sonos units to be ethernet wired to the core network to allow stable grouped play with delays set to the minimum, a requirement for lip sync when the TV audio is a feed.

For a plain vanilla set up of Connect to AVR where the former is a source of music, lip sync, as quoted, is indeed irrelevant.

But the OP makes an interesting point about the centre channel still being useful in such cases; I have never tried out that to comment on whether that brings about an improvement in the music listening experience because the last time I used an AVR was a couple of decades ago. I realised then that a full wired HT set up was more clutter than what the added audio effects were worth; my TV sound improved enough for my needs by just a stereo amp and two quality front speakers, and that has remained my TV approach since then. If I want to watch Top Gun/Maverick in all its glory - which is a rare need - I go to the multiplex nearby.

ratty

But the OP makes an interesting point about the centre channel still being useful in such cases; I have never tried out that to comment on whether that brings about an improvement in the music listening experience because the last time I used an AVR was a couple of decades ago. I realised then that a full wired HT set up was more clutter than what the added audio effects were worth; my TV sound improved enough for my needs by just a stereo amp and two quality front speakers, and that has remained my TV approach since then. If I want to watch Top Gun/Maverick in all its glory - which is a rare need - I go to the multiplex nearby.

FYI: https://en.wikipedia.org/wiki/Trifield

K

Kumar

Interesting, and this was my finding when I was seeing if I can usefully deploy a spare play 1 unit a year ago. In my Connect Amp + Quad 11L stereo listening zone, I placed the 1 unit at the centre between the Quad speaker pair, and grouped it with the Connect Amp. It took me some time to get both at the same sound levels, but when I then sat back and did some critical listening, all I found was that the music was louder - no change perceived in sound stage or music quality. Since the Connect Amp has enough headroom on its volume control in that space, louder was no benefit, and I put the 1 unit in a drawer where it still languishes.

I don’t think that any fancier tech than what this little experiment contained will bring about noticeable change to the listening experience in my space.

T

TheRealAdrianAuthor

Trending Lyricist I

Interesting, and this was my finding when I was seeing if I can usefully deploy a spare play 1 unit a year ago. In my Connect Amp + Quad 11L stereo listening zone, I placed the 1 unit at the centre between the Quad speaker pair, and grouped it with the Connect Amp. It took me some time to get both at the same sound levels, but when I then sat back and did some critical listening, all I found was that the music was louder - no change perceived in sound stage or music quality. Since the Connect Amp has enough headroom on its volume control in that space, louder was no benefit, and I put the 1 unit in a drawer where it still languishes.

I don’t think that any fancier tech than what this little experiment contained will bring about noticeable change to the listening experience in my space.

If I understand correctly, this setup with the extra Play:1 means that the Connect Amp will be correctly splitting out Left and Right stereo signal to the Quad speakers. But the Play:1 will be playing both the left and right signals combined into a single Mono channel. So placing the Play:1 between the two Quad speakers will just mess up the stereo image as you will now have the Left only sounds coming from both the Left speaker and the central Play:1. Right only sounds will come from both the right and centre. Depending on volume levels, I guess this would sound like a wide mono stage? Certainly not an improved stereo stage.

The problem with a 2 channel ‘stereo’ setup is that centre stage sounds come from both left and right speakers. Hence if you are not sat exactly equidistant from both speakers then the sound stage is distorted.

A Trifield or similar effect produced by an AV amp, results in sounds from the left of the stage coming only from the left speaker, sounds from the centre only coming from the centre speaker and right stage sounds only coming from the right speaker. The result is that the centre sound is ‘cleaner’ and the sound stage is less listening position dependant.

Its not quite as simple as that as the centre speaker is usually a small unit that has poor bass response. So the AV amp leaves bass on the left and right channels. Or sends it to a separate subwoofer; which allows smaller, less obtrusive left and right speakers as well (often preferred by ‘the other half’ sharing the sofa:-))

But ….. the software signal processing needed to produce this better ‘stereo’ sound stage results in the sound from the AV amp being delayed relative to acoustically close Sonos only systems. Which is why we need a function in the Sonos setup to provide a variable delay to compensate for the addition signal processing in the AV amp.

C

craigski

Local Superstar

A Trifield or similar effect produced by an AV amp, results in sounds from the left of the stage coming only from the left speaker, sounds from the centre only coming from the centre speaker and right stage sounds only coming from the right speaker. The result is that the centre sound is ‘cleaner’ and the sound stage is less listening position dependant.

Don’t forget the kitchen speaker. If it was in sync, you would also hear the other speakers from the Kitchen, so all of this would distort the ‘effect’ the Sony Amp is trying to synthesise.

K

Kumar

If I understand correctly, this setup with the extra Play:1 means that the Connect Amp will be correctly splitting out Left and Right stereo signal to the Quad speakers. But the Play:1 will be playing both the left and right signals combined into a single Mono channel. So placing the Play:1 between the two Quad speakers will just mess up the stereo image as you will now have the Left only sounds coming from both the Left speaker and the central Play:1. Right only sounds will come from both the right and centre. Depending on volume levels, I guess this would sound like a wide mono stage? Certainly not an improved stereo stage.

A Trifield or similar effect produced by an AV amp, results in sounds from the left of the stage coming only from the left speaker, sounds from the centre only coming from the centre speaker and right stage sounds only coming from the right speaker. The result is that the centre sound is ‘cleaner’ and the sound stage is less listening position dependant.

I noticed no degradation of the sound stage/image caused by a single play 1 in the centre. Of that I am certain, ymmv. No improvement either. So I put it away.

As to the second para quoted, I can not comment, never having heard the outcome. But I doubt I will pursue that even if available, since my Quad pair does all that I need for good stereo sound in the space.

ratty

I can buy the argument for Trifield in a situation where listeners are off-axis. Where one is on-axis -- the ‘sweet spot’ -- adding a further transducer is likely to do more harm than good IMHO, given the need to maintain phase coherence and so forth. Certainly in any critical music listening I never feel the need to further anchor central sound images; they’re already there and pin-sharp.

K

Kumar

I think this will depend on where the listening position is, when not ideal in terms of the distance from the speaker plane. Where closer than ideal, this Trifield thing will help imaging where without it there may be a hole in the image at the centre. But where further than ideal, as is the case at my end with the listening distance to the speakers more than the distance between each speaker, it won’t make a difference.

T

TheRealAdrianAuthor

Trending Lyricist I

I think this will depend on where the listening position is, when not ideal in terms of the distance from the speaker plane. Where closer than ideal, this Trifield thing will help imaging where without it there may be a hole in the image at the centre. But where further than ideal, as is the case at my end with the listening distance to the speakers more than the distance between each speaker, it won’t make a difference.

All I can talk from is my experience. I have 3 different systems in 3 different rooms. All are based on Meridian surround sound processors. All 3 started off as simple 2 speaker systems. Once I moved onto watching DVDs on one system and upgraded it to surround sound, there was no going back. Music, speech and everything else just sounds more convincing and lifelike.
Even on my office system which has a far from ideal speaker layout - my head is about 0.75m from the centre speaker - I enjoy the listening experience.
But then I’m a ‘practicalist’ rather than a ‘purist’!

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