1) Connect your Subwoofer to the Sonos Amp.

2) Disconnect your bookshelf speakers from the Amp (please disconnect the speakers from the Amp side by removing the speaker wire adapter).

3) Now test playback with only the Subwoofer. Does this work properly?

4) Regardless of the result, please submit a diagnostics while it is playing in this mode.

5) Next, re-attach only the speaker adapters to the Amp but without the speaker wires. You should effectively only have the Sub and adapters plugged.

6) Once again, please test playback and provide a second diagnostics.

7) Lastly, re-attach the speaker wires to the adapters and test one more time along with submitting a diagnostics after completing the test

I am having the same issue. I have a sonos amp connected to two standard stereo speakers and a wrs subwoofer. No sound coming out of the sub...

I had the same problem when I got my amp and connected my subwoofer with a simple rca cable: the sub output was very low and I had to crank up the sub level in the Sonos app. Everything was fine after I switched to a y-cable (1-male to 2-male), now connecting both (L+R) inputs of my sub. These cables are available for around $10. Maybe worth a try...

 Can anyone confirm this resolves the issue? This would seem to a ridiculous oversight by Sonos if true.  

For anyone that wants to remedy this major flaw in the AMP, you can go to amazon and search for “MCM Stereo LINE PRE-Amplifier, 15DB, 12VDC” and add that unit between your 3rd party sub and your AMP’s sub output. There’s no need for Y cables when using this with a mono (single RCA) connection, as you are able to use just use one side of the pre-amp.

AudioControl Rialto 600 with a Sonos Port.

Oh dear, how misguided is it possible to be?  This has not been ‘deliberately disabled’.  Why on Earth would Sonos do that?  The nature of the connection of surrounds in Sonos is that they take their data in a passive way from the device running the HT setup (Playbar, Playbase, Beam or another Amp), and in this role it has not been possible to control the Sub output  The lines-in on surround speakers are similarly affected and cannot be used.  For similar reasons you cannot play Airplay 2 to surround speakers.

So do you really believe that Sonos have decided deliberately to deny their customers a whole range of features that might be useful to some of them?  

You can use the third party subwoofer where an Amp is used as the main ‘room’, i.e. for the front speakers.

No it is not “just a feature overlooked by Sonos engineers” or a ploy to sell you a Sonos Sub.  It was explained quite plainly why it isn’t possible, it’s because the surrounds only get a surrounds signal from the HT decoding unit.  Otherwise, why would they take the time to make it possible when the Amp is used as front speakers, and not possible when used as surrounds (or even give you a sub output at all)?  

Same issue here, quite pissed off because I paid a lot of money to integrate my HT to Sonos. No bass at all. Don’t know what to do.

You really have to question quality of product and why any of the professionals they use in advertising ( which makes users believe they are active users and listeners)  did not pick up on this issue up. You decide on why, I won’t say what I think.

So is bass still set to 15 GDaz?

What brand and model of sub is everyone using and how do you like it? How low can your sub go?

Yes, I still find that I have to keep Sub Level high in the Sonos App (currently at 14 out of 15). Then also need to bump the bass up a bit in the EQ (+3). These settings are both on the Sonos Amp side. Then on my Pioneer subwoofer I have the volume turned way up (I remember when driving it from other sources the bass can be overwhelming). So my guess is that the subwoofer level output by the Sonos Amp is low (even relative to their old ZP100). My subwoofer is able to compensate, but how well it works will likely depend on the third party subwoofer’s ability to provide enough bass from a weak signal. (At least this is my theory - I haven’t measured the subwoofer signal directly.)

I’m about to buy the AMP to connect a 3rd party Subwoofer with a pair of Play:5 - Nothing else will be connected to the AMP.  Would I have the same issue as mentioned in this thread?

Even if this works, it will involve clunky workarounds. Why bother? Why not just get a Sonos Sub?

My issue is that the amp sometimes takes a bit to triggger my sub after my sub goes into standby.  Unfortunately my Kef sub doesn’t have a force on feature.  I’m not sure if this is related to the low levels everyone’s talking about.  For instance my children watched a show today and sub wouldn’t kick on.  I switched to Amazon music played a song, finally my sub turned on.  Then I went back and watched the show.  I just increased the sub levels to see if that helps with the triggering.  

So, i have noticed a few things here:

I fort got AMP when it came out, the version of IOS app allowed me to get granular and adjust sub. Perhaps the engineers need to go back and look at that version.  I also when i installed the AMP when it first came out, i was using a Polk SW10, worked great, lots of bass, actually had to turn it down.  I recently got a Klipsch 12 sub, hooked it up nothing, reset AMP, got nothing.  Hooked up Polk and did a reset as well, nothing.  Something with the newer app versions seem to be causing issues with sub out.

The also stark reality, is that you should NOT be adjusting to +15, as it will lead to blowing something out if you have it turned up.  With things at 0, if anything, by default, this AMP SHOULD only need minor adjustments, not a +15 just to get things working.  

I truly hope they get this figured out.

I’m a Sonos noob ready to buy a Sonos amp to replace my old home theatre receiver but the wired subwoofer issue here is keeping me from purchasing. I have a good powered subwoofer I like and see no reason to have to buy a new $700 wireless Sonos one. I want to use the amp, 2 bookshelf speakers (with center channel emulation) and my sub which is easily wired to the amp. I’m not using any surround speakers, I have them now and have decide to give them up and the center channel too to keep things simple and clean. I don’t watch a ton of action movies, more likely to listen to music. 
 

So, does the powered subwoofer output work or not? I’m not buying it unless it does. 

Just got my Sonos Amp and having same issue -- no output from powered sub that works fine. There seems to be no real resolution form Sonos on this issue.

I’m waiting on delivery of the upgraded speakers I was planning to use (including a matching powered subwoofer) and will see if this is resolved or if the new setup is acceptable without a sub (assuming nothing is magically resolved with new subwoofer)

Played around with this setup a bit more and changed the Sonos settings to max (Bass +10, Sub Level +15), and tweaked the sub crossover and volume to what should be a scary level of bass and I *am* getting *something* out of the subwoofer, but I’m not impressed so far

Yeah - it seems that the subwoofer output is miscalibrated. I hope that it is a software issue, and not a hardware issue (like a lack of voltage to that jack). 

I sure wish Sonos would pop by this thread and give us an update

Which sub is it exactly (model no.) and have you telephoned Sonos Customer Care about the issue? What did they say?

The sub is a Cerwin Vega HT-S10A. So far phone support has tried running diagnostics, says the Amp detects the sub connection, and has gone round and round telling me to turn up the volume (because i turned it down… because I’m on the phone… to phone support ) 

“the problem is not with the Amp, everything looks fine from this end”

AWHS has it right about what to do with setting up your 3rd party sub. I have the Martin Logan Dynamo Sub 1600X with the Martin Logan Wireless kit connected to the Sub Out of the Sonos Amp. I also own Sonos Connect Amps (which were easier to set up with a 3rd party Sub). With the Sonos Amp I also drive a pair of Paradigm Studio 60 v3 tower speakers.

So yes, go to the Sonos Settings and add sub, stay away from the Sonos Subwoofer settings. This section should be a little more clear.

You may be best to have your 3rd party sub always on as opposed to standby. With the Sonos settings have the sub level up high and adjust other settings according to your sub manual and cater to your room size and placement. Sub adjustments can be a science. Note : The Martin Logan Dynamo Sub has an app to fine tune it’s settings from your couch via Bluetooth. No need to adjust the manual controls on their latest higher end subs.

As for the Sonos Sub, it is not over priced for what it does. It’s impressive, I use one in another zone with a Sonos Connect Amp. But it’s no match for the Martin Logan Dynamo 1600 :)