Ultimately, only you will know if AMP is an acceptable replacement for your present stereo amplifier. You could add a PORT as a link to ARC. Port would be an analog source for your amplifier.

With respect to the 70ms latency: You are stuck with the 70ms with respect to analog Line-In, however, ARC adds its own latency of about 35ms to TV audio. This results in an approximately 35ms offset between ARC and a Grouped player when listening to TV audio. When listening to music sources all of the Grouped Rooms will be time aligned. If you are playing TV audio in Grouped Rooms, you can adjust the ARC’s TV Dialog Sync to delay its audio an additional 35ms. Of course this might damage the TV’s Lip Sync slightly. My experience with TV station Lip Sync is very poor and the added audio delay might actually be constructive. And I find that Lip Sync varies from program segment to program segment.

You must also consider the physics of the situation. Sound is pokey and travels at approximately one foot per milli-second. If your stereo speakers, driven by AMP, are about 35 feet from ARC, sound leaking from ARC to the stereo room will actually be in sync for a listener in the stereo room. (while listening to TV audio in both Rooms) When listening to Grouped music sources, both rooms will be time aligned, but the leak between rooms will be 35ms out of sync. For an observer in either room the leak from the other room will seem late. If there is minimal audio leakage from the other room, latency doesn’t matter unless you are attempting to support a video linked screen in the stereo room with the screen in the ARC room.

It would be very inconvenient to move SUB from room to room, but you could temporarily add SUB to the AMP room as a test. If SUB offers a significant benefit for your music listening, then you need to decide if adding a second SUB is worth the cost.

There is another track worth considering: If your current speakers image well and would be placed relatively close to the TV, a physical center channel is redundant. This suggests replacing ARC with AMP. Depending on your physical arrangement the stereo speakers may be too close for proper imaging when listening to music and the stereo speakers will not support Dolby Atmos.

Hi Buzz,

Thank you very much for your very quick and detailed answer, and please apologize for my late answer.

In order to clarify my request, I need only to have a good installation in one place. No other room where I want another TV synchronized, video or audio.

The 70 ms delay is coming from my Sonos Community readings, expressing the necessary time for Sonos to synchronize all speakers in Wifi throughout the different Sonos « rooms » which are linked together (as I understood). This is not an issue for music, but could become an issue if front speakers attached to the Amp have a delay with the ARC installation, which will be the case if  the Amp is in its own Sonos « room » grouped with the ARC’s room. This isn’t related to an analog connection.

If the soundtrack is delayed by 35ms (I hesitated a few ms to understand that you were talking about one foot per ms, and not on foot per second  ), I can imagine that it can be acceptable. 

Now if the Amp is bonded with the Arc, the sound coming from the 2 cabled speakers will be surround sound coming from the front speakers, and I don’t know if this can disturb the overall experience. 

Regarding the sound volume, if the Amp is bonded, I can imagine that it won’t be possible to manage the volume separately, as it is possible with grouped rooms. 

Anyway, I’ve in-between ordered an Amp, and I will have many answers soon.

If you have any guidance at that stage, I would be very happy !

Again, thank you for your support.

Regards,

Pierre

A few points to make.

1st - Your option 3 is not possible.  You can only have one set of surround speakers in a HT room, not two.  You cannot have a pair of Ones for surround and an amp (with two passive speakers).  Related, I would not put surround speakers in the front of the room either.  I get why you want to do that for music purposes, but it defeats the point of have a home theatre setup to begin with if you’re going to put speakers in the wrong place.

I think I would go with your option 2.  Actually, I pretty much did.  Only difference is that I’m using a pair of Fives rather than an amp, and I am not attempting to combine the two <rooms> in any way.  The Arc HT used to be called ‘Family Room’.  After getting the Fives, I renamed the Arc HT to ‘Main TV’ and the Fives are now ‘Family Room’.  The Arc is never playing music and never groups with other rooms in the home (unless it’s the audio source).  The TV remote controls volume for Main TV most of the time, and the Sonos app or voice control is volume for Family Room. I am pretty much the only operator of the system, so I don’t worry much about how others may think about how easy it is, although it seems pretty straightforward to me.

Sorry about my slow typing skills. I edited my post to correct the speed of sound.

To make the physical centre channel redundant for dialogue, the stereo placement rule applies even here: the two speakers need to be as far from each other as the viewing position is from each. And of course, the TV needs to be close to the exact centre of the two speakers. With this set up, the dialogues still appear to come from the TV, in even an uncanny way.

But the problem here is the inability to separately control dialogue volume levels in the way a HT centre speaker allows, so in effects heavy movies the overall sound levels have to be too high for the dialogue to be properly heard. I use subtitles in such cases.

My two cents, based on:

1. Anyone that is used to listening to music in stereo with good stereo imaging will never find the sound from a bar good enough - it isn’t that bars are bad, it is that physics won’t let them fully compete with the benefits of two physically separated front speakers to deliver a sound stage.
2. If these front speakers are of a design yielding good bass performance, a Sub can be dispensed with for music and for TV. Except maybe for disaster movie fans who want to feel the effects by how the room gets pressurised.
3. Any bar is also a compromised solution for TV because many effects pan across the screen even beyond screen width. Again, this needs two separated front speakers to deliver the designed effect in the best way.

An assumption, since I do not know atmos - if this is well delivered by a modern and capable AVR, surround may not be as necessary given the inconvenience of their wiring.

Based on the above, I would use a AV receiver, with high quality and bass capable front speakers, placed for best stereo imaging. A centre speaker would be used for a dedicated centre channel. Presumably there are some more things that the AV receiver will have to work with to deliver atmos effects. But that is all that is needed, other than ensuring that the AV receiver has a direct stereo mode, especially if a Sonos interface is to be used in the guise of a Port wired to the receiver.

Music play would then be using this direct mode, with the Port as source. Stereo sound quality will be limited in this case by front speaker quality and placement alone. The direct stereo mode would allow other Sonos speakers, if used, to be in perfect sync with this zone.

For TV, the centre channel would be brought into play by coming out of direct stereo mode, along with the atmos kit, via the full capability of the AVR. As stated, a Sub may not even be needed, nor any surround speakers.

But any TV supplied audio will not be capable of being piped to other Sonos zones except by a complex work around that I can elaborate on if asked.

There are multiple schemes at play. Traditional stereo types are bound to two speakers and possibly an added subwoofer. It’s not hard to imagine a 12.4 or more system for multi-channel surround buffs.

There is another scheme that is gaining traction -- Object-Based Audio. Here, a musical instrument is assigned a position in three dimensions during recording and the playback system delivers this to the listener. This “delivery” can be done with multiple methods that are not fixed to a predetermined playback speaker configuration. This speaker configuration can be headphones, traditional speakers, or even ultrasonic transducers that do not emit anything in the traditional audio band.

Routinely we are using technology in museums where an artwork discussion is presented to visitors standing in a specific area. The next artwork along the wall is also delivering its own presentation. There is no presentation overlap for the visitors. At a trade show a fellow walked up behind me and introduced himself. When I turned to face him, there was nothing. In another demo (using two speakers) I was sitting in front of an audio mixing console and given a joystick. The joystick controlled the soloists position. i could place her out front somewhere or have her sit beside me at the console. In another demo we were given a simulated haircut while wearing headphones. It was rather convincing. As the scissors moved around, hairs stood up and waited their turn.

Sound bars are increasingly moving into this Object-Based arena.

I realize that all of this trickery chaffs the traditional stereo person, but I’ll point out that live music is a 3-D experience. It’s still early in 3-D audio development

This sounds fascinating and worth a check out once mature for the home. But the question is whether this can replace a conventional stereo which physically replicates the way sound is heard in a live gig with the band/singer/orchestra placed on a similar stage in front. After all, one does not listen to an orchestra sitting in the midst of it - an experience that the quoted tech will seek to replicate.

Which isn't to say that once accustomed to it, it will not provide the better listening experience. Only time will tell.

Certainly this will make the first person shooter games even more horrifying...

‘Reality’ depends on what one is used to. If one plays in the group, one is surrounded by instruments. The sound is different in the front rows and back rows of the audience. Particularly for rock concerts, the sound presented to the audience is mostly from a sound reinforcement system and this is quite different from a studio sound. Which sound is ‘real’? Which version should be presented to a home listener?

Ideally, various options, and by that I don't mean the ones available on cheap equalisers today. And ones that don’t need more wired/wireless speakers.

One way to start would be for a bar to use this object based tech to accurately replicate the sound of two front speakers and thereby create the stereo image for music that will satisfy those that are used to the sound stage from smallish live gigs. 

I suspect that rather than the sound signature from bars as such, it is this lack that people perceive as loss of quality when they use Sonos and other bar based solutions for listening to music. I know I do.

But it is high time that the home audio scene that has been largely stagnant on the sound quality front for almost half a century, made some real and meaningful advances. 

I find it a little difficult to blame the audio industry for not making significant increases in audio quality, because that’s not exactly what the market has been calling for.  It’s well known that audio quality too a big hit when people started opting for the digital convenience of  mp3s and ipods over quality.  And then further went for streaming and voice control on puck speakers, again for convenience and ease of use, as well as costs, over audio quality.   And neither of these trends were really pushed through the traditional audio speaker industry, but by outside big tech.

Of course now, the focus seems to be on Hi Res audio, which many see as snake oil rather than improved quality (without getting into that debate).  You can blame traditional audio for that in part, but it’s again big tech that’s pushing that through streaming services.

Besides all that, there is only so much that a speaker maker can do considering the acoustic environment, aesthetic requirements, and other limiting factors in a home environment.  I mean, we all know that soundbars were never an improvement on audio quality, but they are popular with customers due to cost, ease of use, an aesthetic value over other options available.