I received a reply from a Sonos engineer who told me that when the CONNECT:AMP is used for surrounds, both the WiFi and the Line In features of the device are disabled. I asked him why the WiFi is disabled (I imagine that it's hard to guarantee latency if you're not wired to the PLAYBAR).
A couple of things on this:
- With WiFI disabled, why doesn't the player still show the wired path info in the Network Matrix?
- Why is Line In disabled when the CONNECT:AMP is being used for surrounds? Sonos has never provided a satisfactory explanation for this. I can understand that if you're listening to audio from the PLAYBAR and get audio on the Line In port, you may be surprised that the surround audio is replaced by the Line In audio, but let the customer decide the behavior of this, not Sonos. Related to this is why the players don't automatically switch back to whatever stream they were playing and automatically regroup (if grouped) when the Line In audio is silent for some period of time.
I received a reply from a Sonos engineer who told me that when the CONNECT:AMP is used for surrounds, both the WiFi and the Line In features of the device are disabled. I asked him why the WiFi is disabled (I imagine that it's hard to guarantee latency if you're not wired to the PLAYBAR).
A couple of things on this:
- With WiFI disabled, why doesn't the player still show the wired path info in the Network Matrix?
- Why is Line In disabled when the CONNECT:AMP is being used for surrounds? Sonos has never provided a satisfactory explanation for this. I can understand that if you're listening to audio from the PLAYBAR and get audio on the Line In port, you may be surprised that the surround audio is replaced by the Line In audio, but let the customer decide the behavior of this, not Sonos. Related to this is why the players don't automatically switch back to whatever stream they were playing and automatically regroup (if grouped) when the Line In audio is silent for some period of time.
A surround setup operates via 5 GHz, a LineIn connection works only via 2.4 GHz (for music purposes), hence the LineIn is disabled when ConnectAmp / Play:5 are being used as surrounds.
When speakers are bonded as surrounds things work a bit differently. The Playbar / base runs the show and uses direct peer to peer communication to send the rear channel streams. With the Play speakers that is over 5 GHz for its low latency. The C:A has no 5 GHz radio hence the wires.
But the surround system is something of a self contained unit. My assumption is that the different nature of the connection makes it technically difficult to get line in audio out.
Note that when P5 speakers are used as surrounds the line in is disabled.
I received a reply from a Sonos engineer who told me that when the CONNECT:AMP is used for surrounds, both the WiFi and the Line In features of the device are disabled. I asked him why the WiFi is disabled (I imagine that it's hard to guarantee latency if you're not wired to the PLAYBAR).
A couple of things on this:
- With WiFI disabled, why doesn't the player still show the wired path info in the Network Matrix?
- Why is Line In disabled when the CONNECT:AMP is being used for surrounds? Sonos has never provided a satisfactory explanation for this. I can understand that if you're listening to audio from the PLAYBAR and get audio on the Line In port, you may be surprised that the surround audio is replaced by the Line In audio, but let the customer decide the behavior of this, not Sonos. Related to this is why the players don't automatically switch back to whatever stream they were playing and automatically regroup (if grouped) when the Line In audio is silent for some period of time.
A surround setup operates via 5 GHz, a LineIn connection works only via 2.4 GHz (for music purposes), hence the LineIn is disabled when ConnectAmp / Play:5 are being used as surrounds.I am unclear why a line in source should be limited to 2.4 GHz wireless??? Once it has been converted from analog it is just digital data.
A surround setup operates via 5 GHz, a LineIn connection works only via 2.4 GHz (for music purposes), hence the LineIn is disabled when ConnectAmp / Play:5 are being used as surrounds.
A surround setup also works exclusively wired - I have a PLYABAR, a SUB and a CONNECT:AMP that are all wired and all of which are using the wired connection, not SonosNet.
I don't see the relevance of the frequency of the wireless transport being used as to whether or not analog audio input can be supported. Certainly I have many devices on my LAN that connect to my WiFi system at 2.4GHz and have no problem streaming 4K UHD video and Dolby Digital 7.1 audio, so transporting two channels of 48kHz audio (even uncompressed) should not be an issue.
I think there is some other reason that Sonos disables Line In on a CONNECT:AMP being used as a surround player. I'm not so sure it's a technical reason either, it might be a "user experience" issue.
I think it is extremely unlikely that it is anything other than technical, but only Sonos can tell us for sure. I suspect, as I have said, that it is something to do with the nature of bonding in a surround setup, and not the wireless or wired technology itself. But I don't know.
Anyway, that's what they said to me on the German board. Perhaps can a mod elaborate on the technical reasons.
With the CONNECT:AMP it's entirely technical reasons why it doesn't work. The Amp was never designed to operate as surrounds for home theater and it was added later per request, that's why the experience for setting it up involves hidden pages. Basically, everything the CONNECT:AMP has processing and memory wise has to go into operating as surrounds when it's in that configuration. It doesn't have the juice to handle anything else. That's also why it needs to be wired in, the 2.4GHz doesn't have the bandwidth to handle transferring the data needed for surround behavior.
Line-In is disabled on all surrounds for similar reasons. For the Play:5 gen2, it's to keep things simple as well, in addition to saving the processing for what's needed. Imagine trying to play TV audio, and also send the line-in connection from a surround speaker over to another room? If it were possible, it'd be a recipe for disaster.
When Sonos is set up in a surround configuration, the main player is always the Playbar, Playbase, or now the Beam. That player runs the show and determines just about everything, the others are all set up as secondary points, following the orders from the main device.
Thanks, Ryan, for the clarification. 🙂
Yes thanks Ryan.
With the CONNECT:AMP it's entirely technical reasons why it doesn't work. The Amp was never designed to operate as surrounds for home theater and it was added later per request, that's why the experience for setting it up involves hidden pages.
But Sonos could add the ability to configure the CONNECT:AMP as surrounds in the various controllers, they just choose not to, it's not a technical issue that there needs to be hidden web pages to configure this. I would even go so far as to say that having hidden web pages is way more resource intensive in the player than a simple interface that the controllerplayer share as they do for other aspects of operation.
Basically, everything the CONNECT:AMP has processing and memory wise has to go into operating as surrounds when it's in that configuration. It doesn't have the juice to handle anything else.
Do you have a more technical explanation of the jucie issue?
Let's think about this logically for a moment. The CONNECT:AMP has enough jucie to operate as a stereo player and to play the Line In audio both to its speakers and to broadcast that audio (digitally) on the network to other players if it's configured to do that. Anyone disagree with that?
OK, when the CONNECT:AMP is operating as a surround stereo player, I'm almost 100% certain that the Dolby Digital decoding is not being done in the CONNECT:AMP but in the PLAYBAR, and the CONNECT:AMP is just getting a stereo audio stream from the PLAYBAR; this stereo audio stream happens to be a stereo (or two channel) surround audio stream, but it's not some magical audio stream that squeezes the jucie out of the CONNECT:AMP. Does anything disagree with my assertion here?
Moving on, assuming you agree with both of my previous assertions, I can see how the CONNECT:AMP might not have enough jucie to handle both the two channel surround audio stream from the PLAYBAR and a separate analog audio signal on the Line In. This jucie issue probably has to do with the ability of the internal processor and OS to keep four audio streams synchronized, and I can believe that there may be RAM limitations for buffering audio data that preclude the CONNECT:AMP from handling four separate audio channels, two of which are coming from one source and the other two of which are going to other players on the network. Anyone disagree?
Now what Sonos could do, and I believe that this is within the capabilities of the CONNECT:AMP hardware and firmware, is when the CONNECT:AMP is being used as surrounds and when it detects audio on the Line In jack, it could ungroup itself from the PLAYBAR and become a regular non-surround player for the duration of the Line In audio being present. Once that audio is gone for a user-configured amount of time, the CONNECT:AMP will rejoin the PLAYBAR as a surround player. In this way, the CONNECT:AMP is never being called upon to do anything more than it would normally be called upon to do, i.e. it would never try to be both a surround player and a regular stereo player.
That's also why it needs to be wired in, the 2.4GHz doesn't have the bandwidth to handle transferring the data needed for surround behavior.
I'd like to understand why 2.4GHz is unable to handle passing two channels of 48kHz audio with an acceptable latency, especially over SonosNet where there are no variables such as user-supplied WiFi infrastructure. How were people playing audio over 2.4GHz WiFi links for years before Sonos came on the scene? And how do people watch video and audio over 2.4GHz WiFi infrastructure (or 1.8GHz cellular infrastructure!) without major issues?
Line-In is disabled on all surrounds for similar reasons. For the Play:5 gen2, it's to keep things simple as well, in addition to saving the processing for what's needed. Imagine trying to play TV audio, and also send the line-in connection from a surround speaker over to another room?
See above concerning never having a player handle both surround audio and Line In audio (i.e. four different audio streams simultaneously).
If it were possible, it'd be a recipe for disaster.
What would the disaster be? By definition, if it were possible, then it would be possible and hence not a recipe for disaster would it?
When Sonos is set up in a surround configuration, the main player is always the Playbar, Playbase, or now the Beam. That player runs the show and determines just about everything, the others are all set up as secondary points, following the orders from the main device.
Can you more clearly explain what you are saying here and how this would prevent using the CONNECT:AMP in the ways I have described above? Certainly I can see a bidirectional handshake where the CONNECT:AMP, functioning as a surround player, tells the PLAYBAR that it is going off-line a surround player, then at some time later, tells the PLAYBAR that it is coming back online as a surround player. As my good friend at NASA likes to tell me, "This ain't rocket science".
p.s. PLAYBAR in this discussion = PLAYBAR or PLAYBASE or BEAM
Jeez who cares?
I get where you're coming from, Michael, and I'll be sure to pass along your interest in wanting this as a feature. While it can be fun to go into details and explore what might be possible, in the end, using the CONNECT:AMP as home theater surrounds isn't a feature that has the full Sonos polish on it. We added it on after requests came in from our installers and customers to find a way to make it work. The CONNECT:AMP was never designed to be able to handle this task, and as part of the way we got it to work, the CONNECT:AMP can't support handling line-in audio when it's configured as a surround speaker.
There are several technical limitations at play here, some of which could be worked around theoretically, others that would likely require new hardware. One big thing to consider when it comes to TV audio is that it doesn't just have to transfer the data for the sound and process it, but the playback has to be in sync with the source, and any other channels, without much time available to buffer it for loss. The 5GHz or wired connecting (in the case of the CONNECT:AMP) is what it takes for this since it speeds up the transfer.
