Using old Bluetooth speakers in multi-room/multi-channel speaker setup

October 27, 2020 4:59 AM

Does an open-source or cheap DIY multi-room speaker software or hardware thing exist that will let me use my old speakers like a Sonos multi-room setup? The more I read, the more confused I am.

I was recently gifted a new UE Wonderboom 2. It was a surprise when I learned you could pair 2 of the same model together to create stereo, a further surprise when I realized my new phone (Samsung Galaxy S20 Ultra) has a feature to do this on 2 (but only 2) different speakers of any brand, and a disappointment when it had a 1 second or so delay that sounds echo-ey and very unpleasant, and that I couldn't adjust on the phone. So I dived down the rabbit hole...??? CONFUSED. Sonos, Google, Bluetooth versions, brand and model incompatibility... I've had wired bookshelf speakers, off-brand Bluetooth receivers, a portable Bose thing from 2015, and I recently moved, and now it's time to redo my audio setup. Is there an app, software solution, or hardware that will let me link them together in a real multi-room and multi-channel setup, with adjustable EQ and delay for each Bluetooth output? A DIY Sonos thing? An app for Android TV sticks maybe? Hubs/adapters I can plug into headphone jacks?

I have/can obtain older phones or laptops to act as controllers, and I'm willing to invest a little cash and time in the project. I'm also perfectly happy with a stereo sound signal, all this fancy 5.1/9.1/DSEE HX/all these numbers and letters I'm an idiot play my podcast. Going down the wireless audio rabbit hole, I haven't found a "go-to" open source solution like, say, WDDRT/Tomato for routers, but it seems like with all the old audio hardware kicking around, there ought to be? Am I missing something? Is my only option to drop $2,000 and junk my old perfectly-acceptable speakers because they lack a software update?

posted by saysthis to Technology (10 answers total)

There are a few software projects that will run on a Raspberry Pi to accept your music (over Bluetooth) and relay it to speakers and/or amplifiers. Most are free, a couple are not.

I confess that I have had mixed luck with these, because my amp crapper out partway through and I never finished the project.

That said, many of them are quite polished! The may include integration with audio streaming services, and play your own MP3 (etc.) music files, and also work with a movie set-up.

Using BT will always introduce some delay (and often clipping), compared to cabled connections, but I expect people who actually know about music will comment after me with factually-correct answers. So just see this as a suggestion to temper your expectations -- especially if you are cobbling together something from a pile of parts, because at least some of them will run older versions of the BT protocol.
posted by wenestvedt at 5:37 AM on October 27, 2020 [1 favorite]

If you want plug and play and no open source, a few Alexa dots will do this for you. Google home probably will too. They have 3.5mm outs.
posted by bbqturtle at 5:39 AM on October 27, 2020

Bluetooth is meant to be a cable-replacement technology; at heart, it just sends two channels of audio across short distances.

Main thing to do will be to decide whether AirPlay or Google Cast is better for your mix of controller devices. They have a lot of additional capabilities you’re looking for, like applying an EQ and synchronizing the audio across network/device delay.

Airfoil is commercial MacOS software, but it supports AirPlay and Google Cast to broadcast to a wide variety of devices, including iOS, Android and Windows if they have the (free-as-in-beer) companion “Satellite” apps installed.

I am not a Windows user, but IIRC something like TuneBlade might play a similar role on that platform.

I do not know if AirPlay or Google Cast can assemble arbitrary devices into stereo pairs. Applying an EQ and syncing audio across the speakers/network should be doable via either protocol though.
posted by FallibleHuman at 6:04 AM on October 27, 2020

If you want plug and play and no open source, a few Alexa dots will do this for you.

I was coming to say this, too. I have used Airfoil, and in the olden days a couple of Airports Express, and in the oldener days wires through the ceiling, and and and. In each instance it was cobbled together and you needed to do a little dance to make it all work.

Now we have Echos in most rooms, including a few Dots that are outputted to nicer speakers. We have the microphones muted on each one, and we have collections of speakers grouped together through the Alexa app. You can slice and dice, so if you are having a dinner party (remember those?) you can play music on the main level, or if you are cleaning you can play music room-by-room, or if you want to jam out everywhere you can do that.

I think this will just let you stream (as opposed to playing your own stuff), so that's definitely a limitation. But the trade off is that the sync/controls are pretty seamless.
posted by AgentRocket at 7:27 AM on October 27, 2020 [1 favorite]

If you want multi-room sound that Just Works, run wires and use per-room faders.

If you like endless fartarsing about with beautifully polished digital turds that always over-promise and under-deliver and cost a lot and have endless crazily bizarre failure modes, go wireless. Maybe this time they won't jerk the ball away.
posted by flabdablet at 7:43 AM on October 27, 2020 [5 favorites]

As others have said, Bluetooth isn't really capable of this.

I use (discontinued, selling for a premium on eBay) Google Chromecast Audio devices for whole house audio. It is USB powered and has a 3.5mm audio out jack, no microphone or speaker of its own. You can cast Spotify or Plex to a group of them and they manage the latency to all play at the same time.

They also can interact with the microphoned Google Home devices so you can say "OK Google, play blah blah on Living Room" (assuming you've named your Chromcast Audo "Living Room").

I haven't found an open source project that can play Spotify on multiple devices, the closest I've found is Volumio but I've never had any luck getting Spotify to work on it.
posted by revgeorge at 8:07 AM on October 27, 2020 [2 favorites]

Unless you're really excited about the idea as a project or feel strongly about staying outside of the Amazon/Google/etc. ecosystems, trying to home brew something will probably be more expensive and headache inducing than buying a commercial product. But here's some starting points.

https://www.balena.io/blog/diy-raspberry-pi-multi-room-audio-system/
https://www.technicallywizardry.com/speaker-multi-room-wireless-receiver/
https://www.instructables.com/DIY-Multi-Room-Audio/
https://www.instructables.com/Sonos-like-Wireless-Multiroom-Sound-System/
https://medium.com/the-monolith/how-to-build-your-open-source-multi-provider-and-multi-room-sound-system-4015e761ce7c
https://www.hackster.io/mcmchris/diy-multi-room-wifi-bluetooth-audio-system-hi-fi-2f6eae

Personally I use the (discontinued but findable on eBay) Chromecast Audio devices for the purpose. They pretty much Just Work (tm) and after battling computer issues all day at work it's nice to be able to just hit play rather than worry about whether I need to restart Docker in order to listen to music. YMMV.
posted by Candleman at 8:12 AM on October 27, 2020 [1 favorite]

Sonos makes a device that can do this, but it's obscenely, inexplicably expensive.
posted by mekily at 8:13 AM on October 27, 2020

As per the comments above, we use Echo dots for this purpose (or other Echo devices, but why invest in a more expensive device if you're just plugging them into another speaker?) . You can pair your speakers to them via Bluetooth, or, better yet, use a 3.5mm connector to hardwire them. You can use legacy dots for this purpose, you can usually pick them up for relative peanuts. The system mostly Just Works, my only issue is the crappy user interface on the Alexa app.

Note that current generation google units do not have audio out, which makes them more complicated to use for this purpose.
posted by sid at 11:55 AM on October 27, 2020

If you don't mind tinkering, here's a recent article about using the Mopidy music server software and a Raspberry Pi to do multi-room audio:

https://magpi.raspberrypi.org/articles/build-a-multi-room-audio-system-with-raspberry-pi
posted by wenestvedt at 5:33 AM on October 28, 2020