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. 

I currently have 4 Sonos Amps that I’ve being using for the past 2 months with out any subs. Yesterday I got my SVS Ultra PB16 and for a good 3 hours I couldn’t get it to work, I thought I had a defective Sub, but after being on the phone with SVS support and messing with the Sonos App we came to the conclusion that the signal is way too weak, I was able to get a bit of base by cracking the level to +15 and setting the Sub to Max volume, which it sucks. We actually tested the sub with my Ipad by using RCA to Headphone Jack in the Ipad and its sounds amazing so this confirms the sub is fine. Unfortunately I can’t return my Amps and I dont want to return my sub, so what Im thinking of doing is buying a Yamaha receiver to power my In-ceiling speakers and sub for a true Surround system and control it with a Sonos Port.

Oh and by the way, if You have a Sonos Sound Bar and you want to create a 7.1 system, it wont let you, this is another reason as to why Im considering getting a Yamaha Receiver since Sonos is not all there yet.

Given that this issue is so easy to reproduce It is very frustrating that Sonos has yet to resolve (or even acknowledge it). 

The latter bothers me more and tells me to steer clear of the amp.

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

Bump - this was a key reason i bought the AMP and investsed in this eco system in the first place and the fact it doesn’t work as expected and lack of response is VERY disappointing.

Could we PLEASE get somebody from Sonos to communicate with us exactly what needs to happen to have this working as advertised? I’ve tried everything in this thread (disabled surrounds etc.) and no luck with my Yamaha powered sub which was fine with every other receiver / source i plug it into.

I suspect they realise this is a critical issue with no resolution right now which is concerning :|

I’m connected to several hifi retailers and reviewers here - i will be communicating this issue openly to anybody even considering going down this route. Right now, you should NOT should consider buying the AMP if you have any interest in running 3rd party subs right now.

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”

I don’t know the 3rd party sub you refer to, but presumably Sonos Support were referring to turning up the volume on the sub itself? I know their ‘classic series’ subs support that.

http://www.cerwinvega.com/manuals/home/Classic-Sub_manual.pdf

I got a sub working with my system.

I did not make any changes in my Sonos app and system settings except in the EQ to get the amount of low end I wanted. It kicks whether it’s flat or with the EQ boosted five points, which is my preference.   

The one I tried initially, the Sonos Connect Amp was either not pushing enough gain to trip the amp on or the sub was defective. So since my Martin Logan wireless transmitter has a Left and Right input for my Home Theater sub, I pulled out the right that connected to my Sony amp and used that channel for my Sonos Connect amp (subs are mono anyway so left and right in is pointless), and now I use the same sub for both my Sony entertainment system and for my Sonos zone in the kitchen (it’s one big room anyway). Problem solved for me! The ML wireless transmitter is its own preamp anyway so I don’t have to send a stronger signal to kick on the speaker since it’s wireless. 

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 :)

Hi everyone, thanks for sharing your experiences with different devices and the Sonos Amp. We’re always interested in seeing what you have to say, and are eager to investigate any issues that might come up. Our engineering team has been looking into this issue and would love some more information. Currently, there isn't a major trend that has been identified, but they'd like to see some more cases where subwoofers and the Amp aren’t behaving as expected. 

If you’re having trouble with the Amp outputting low or no audio to a subwoofer and haven’t worked with our support team yet, please feel free to reach out to us using the contact details here. The support team will help sort out issues where possible, and if needed, they’ll gather the right information and get it up to the engineering teams for investigation.

Ryan - I appreciate your input. Is there a case number or something that we should reference when we call in? I spoke with CS at length at this issue a few days ago and was told that they “have never heard of this issue.” Given that this thread has 10K+ views and hundreds of users with the exact same issue, that was frustrating. Please let us know what we can do to facilitate a resolution to this issue.

I am having the exact same issue as others have reported with a REL T/7i sub. No output at all from sub out on AMP. This sub works perfectly on another system. Diagnostic code is 1376304507. I took advantage of your upgrade offer and will have to return the AMP if it does not work with my third party sub. This seems like a serious design flaw. 

Hey, in order to get sound I need to turn the volume control on my sub way up, as well as turn the sub volume on the amp settings page in the Sonos app to +13. Just thought I would mention this in case you haven't tried both of these.  

I've just submitted my ticket to support as well.  Hopefully there's an answer soon.  I'll update here if I get anything tangible.

Just to provide some hope for people. I have the new Amp connected to an Energy sub and Mirage speakers. I’m not using it for TV. It’s all playing perfectly and the subwoofer is powering just fine.

I will say the line level is low and I had to the sub volume knob to about 75% and it’s all the way up in the Amp settings. 

It sounded good playing lighter rock music like Gin Blossoms and thumped when I put on In Da Club by fifty cent.

I purchased my Sonos Amp last weekend to connect to a Sony TV, 2 x B+W bookshelves and a B+W ASW610 sub. I read various posts to work out how to connect the sub and initially tried connecting via a split RCA. This gave me a weak, or non existent signal as described in a lot of posts in this thread. I was freaking out a bit. After reading about LFE channels, and re-reading my sub manual, I connected a single RCA from the amp to the left RCA input on the sub, which I think is the LFE input, and I switched off the low pass filter. It now works well in a surround set-up and puts out a lot of bass. I’m really enjoying the amp. The TV and Spotify sound great to me and I like the look of the amp. The app is really useful and I’ve found myself adjusting the sub level with the app which is really handy.

I’ll be in the same situation - has anyone used a sub that has just a single input with the AMP - I’ll end up with two subs so I’ll have to split the sub out which sounds like it will be a problem.

Hey Ryan S,

Don’t the comments here warrant a closer look at these connections?  Do you really need more people to report in order to escalate the issue?  You can count me in as one of the many people who are experiencing little to no output from our 3rd party amps.  When I put my hand to my amp with it cranked (both in the amp settings and physically on my subwoofer), I can barely feel a vibration.  Also, hasn’t Sonos tested this themselves?  Sounds like it would be a really easy test to perform: drag in a third party sub, plut it in to sonos, and voila, problem recreated.

Any help would be greatly appreciated (especially considering that I dropped $600 on this product)!

Hi Ryan and others,

I have been following this thread with interest.

I have replaced an old Onkyo amp and Sonos Connect, running an Onkyo SKW-501 active Subwoofer with the new Sonos Amp. 

Similar to others I have to have my subwoofer output set to +15 to get a reasonable signal. This in itself is not a problem the majority of the time.

The thing that IS annoying is that the Amp does not trigger the subwoofer to wake from standby whenever it is active. For example I am currently watching the News on TV and the subwoofer is in standby mode. When a bass note plays the subwoofer will kick in but usually with a ~1s delay which is noticeable. When watching a Film/playing a Game this is rarely an issue as there are enough bass notes that the subwoofer wakes from standby and stays on, otherwise after about 15 minutes it returns to standby. There is unfortunately no switch to disable standby mode on the subwoofer. The Onkyo FAQ recommends increasing the output from the Amp, but unfortunately as already at +15 this is not possible. When the sub was running from the Onkyo amp, the second the amp turned on the sub would come on and stay on.

Clearly this is an issue with the Sonos amp outputting a very low subwoofer pre-out signal.

I spoke to Enos at Customer Support and submitted a diagnostic (403792976). I referenced this article. He could not see a fault with the Amp and suggested this was an issue with the Onkyo Sub standby circuitry being “overly sensitive”. Although this may be true, it’s clearly not an ideal situation, and although the plan will be to upgrade the sub in the future that is not feasible right now (the Amp is expensive!). 

He did say he would pass my experience onto your Engineers.

Hopefully if enough people report such an issue a solution will be found.

Thanks,

Oliver

Same issue with my sub and the just bought Sonos amp. Reading this thread makes me wonder if it works with any sub apart from their own brand one.