They have helpfully concluded that it is the fault of my sub, despite my sub working perfectly with my previous setup of a Sonos Connect into a hifi amp. Whenever that amp turned on the sub was instantly on. Why can't the Sonos Amp do this even with it set to +15?

They have an issue. But they won't admit it. 

What is the status of this? I am looking at using the Sonos Amp with either a Rythmik or SVS subwoofer. Does the subwoofer out provide a high enough signal level to drive subwoofers like these?

Is there going to be any valid responses from SONOS in regards to this? I find this type of customer service to be deceptive from a technology company.

I've read that the sub out is only 2 volts (personally I feel it's outdated voltage coming from a car audio guy) , but I would think that is plenty for 90% of the powered subs on the market.

I am looking at purchasing the Sonos Outdoor set with Sonos Amp to start my Sonos journey, but this doesn't appear to be a positive start. I would go to Best Buy and have them connect it all in store, but with Covid closures, that cannot happen anytime soon.

Same issue here - weak signal from the Sonos Amp’s subwoofer output makes it basically useless. I have to set the Sonos Amp to +15 and turn the sub’s amp all the way up to get audible sound from the sub. When I use this exact same sub setup with other sources it literally shakes the house with the sub level at 1/4. There are lots of threads and discussions about this; I find it infuriating that Sonos won’t at least acknowledge the issue. It’s also disappointing the product has such an obvious flaw when all the other Sonos stuff I’ve had has been quite good. I really wish I had come across these discussions before I purchased the Amp so I could have avoided it.

Your mileage may vary but the bug seems fixed on the latest firmware 11.1.

I had to turn the in-app sub level down from +14 to +2 

Me too!
 

I'm not sure yet if it has fixed the “auto-sleep” issue with my sub. But it's definitely fixed the gain issue! It's very loud now!! I've got from +15 to +3, and may go down further yet!

2 hours of TV later - no turn off!

I've halved the gain on the sub, and increased back to about +8 on the app. Keeps the sub alive. 

Puuurfect. 

Means I can now spend money on some new KEF LS50s to go with my Amp!

Hi everyone, we’ve been working on this issue and the most recent Sonos update, version 11.1, should have resolved any low sub output issues that you were seeing. If you haven’t updated already, you may notice that the sub level is much higher after the update, needing it to be turned down. Once you’ve got your sub output tuned in again, you should be all set to enjoy.

Have a good one!

I can confirm this as well - the latest update to version 11.1 seems to have solved the sub output level problem with the Amp. I’m not sure why this went unacknowledged so long, nor do I understand why the fix went out so quietly. Regardless, the Amp now seems to be functioning up to the high standards of the other Sonos devices. A big thank you to whomever was able to identify and resolve the software issue!

Mine is working properly now.  I had forgotten about the issue and was using my setup in the room with the AMP and noticed way too much subwoofer volume.  At first I thought it was where I was sitting so I moved and it was still incredibly high.  I went into the settings and adjusted it down to around +5 and it could still use a bit more adjustment.  I remembered this thread and came back to see if there was an update.  Glad to see this issue resolved.

Naturally, I have the same issue.  Sonos has disabled the sub out if you are using the Amp as a surround configuration.   After talking to someone at Sonos(somewhere in a foreign land) they have informed me that the sub “out” has been disabled since they can't guarantee the quality of the sound when using a third-party subwoofer, however, the same concern does not seem to apply to third party speakers.  I am using the REL sub now on my Amp, and it works perfectly so, I don't believe this is the true reason.  Any sub will work fine, but Sonos wants you to purchase their own sub.

That information you were given is incorrect, as I understand it. The Sonos system is only sending the surround information across the link to the Amp supplying power to those speakers, and has never included the LFE channel in addition. 

The feature has been requested since the initial release of using a CONNECT:AMP to drive surrounds, and has yet to be included. One doesn’t know if there is a technical, financial, or marketing reason as to why it hasn’t been changed. 

Thank you for that info.  It seems I am not alone in this and as long as I want to use my own subwoofer I won't be able to in surround config.

 Another possible option the Sonos tech brought up was not to use the surround but rather group the rear speakers and subwoofer and use it this way, but once the surround is implemented the sub”out “ will be automatically disabled.  I don't know if the “grouping” option would work or not, and if would be able to tell the difference but I imagine if it is not in surround set up I am just getting left and right channels split between the Sonos Arc and rear speaker.   What is your view on this?

Thanks.

I’m not sure what you mean by ‘group the rear speakers and subwoofer’. In the Sonos ecosystem, there is a single ‘room’ which contains the front and rear speakers, so there is no way to add a sub to the rears.

Grouping an additional Amp driving an extra subwoofer would be challenging, due to the addition of the 75 ms delay between the Arc’s room and any grouped room.

Essentially, using a third party sub in a sound bar driven room in the Sonos ecosystem is a non starter. In order to use a third party sub, you have to be using the Amp with two third party speakers up front, which allows the sub port to be active, but forces you into a ‘faux’ center channel. 

Thanks.

So if I want to use a sub with this set up(arc in front, third party speakers in rear) I would need to get a Sonos sub? 

Sonos arc may have enough base for movies and I may not need an additional sub, but I also like to listen to music and my REL sub helps.

If you want a sub in a Sonos ‘room’ with an Arc, then the Sonos Sub is the only option. 

Beyond the extra cost, it’s a good performing sub, imho. I’ve got two of them. I’ve considered a third, bonded with a pair of Sonos PLAY:5s, but haven’t pulled that particular trigger yet. 

Hey guys … Im starting to have the exact same issue described here w/  my Sonos Amp.  my Sonos amp w/ 3rd party sub was working perfectly up until a few weeks ago.  All of a sudden, I can’t hear anything.  My sub just won’t output anything unless I jack the sub volume all the way up and and increase the sub level to +15 in the sonos app.. and even then, its muffled and not impressive at all.  Sub is good … wires are good.  Everyone says update 11.1 fixed the issue, but I’m running 11.2.6 (S1) and having the issue.  Tested another sonos amp I have, same deal.  

For those that now have the issue resolved, are you using the S2 platform or S1?  

Sorry for my stupid question… Do I need a passive or an active sub using an amp with two normal (Bose 251) speakers? 

It’s an active sub, or you can use a Sonos sub - just to add the Amp user-guide/manual is available here too, if you need further information:

https://www.sonos.com/support/en-us/sonos-user-guide/index.html#t=sonos-user-guide%2Famp%2Famp.htm

Thx!

Doing research on Sonos Arc with non Sonos rear surrounds and 3rd party sub and came across this thread. So just to clarify, if I have 2 rear surrounds that are non Sonos along with a 3rd party sub connected to the amp, the sub will not work? Does anyone have 2 speakers and a sub connected to the amp to get a surround sound setup with the arc? If I can keep my sub and rear speakers, I’d consider the amp since my current HT setup is decent. 

@Capthat 

When the Sonos Amp is used for HT rear Surrounds all the Amp ports, including the .LFE Sub port, are disabled. So a 3rd party active Sub can’t be used with that type of setup, you can only use a Sonos Sub when a Sonos Arc is being used for the HT front channels.

Thanks...kind of disappointing that it has the inputs on the amp but they all can’t be used 

I guess there are perhaps technical reasons why the Amp ports are disabled as the Amp just becomes a slave to the Arc master device. If the Amp is set as the HT master device for the front channels (in place of the Arc) then all the ports are not disabled and the 3rd party Sub can be used in that kind of setup, just not when an Amp is used for the rear surrounds.

The only way to connect your 3rd part SUB is to configure your Amp in a separate room to your Arc or centre speaker, if you add the AMP to the same room setup as your Arc then the output is disabled.

This is a bad marketing move and just a money grab to get you to not use your existing Sub and to purchase the Sonos SUB…

If you configure your Amp in a sperate room and add your L + R speaker and Sub they work, but when you put them all in the same physical room as your centre speaker the sound is out of phase and it sounds bad