from Hacker News

Snapcast – Synchronous multi-room audio player

by geekuillaume on 12/29/19, 10:07 AM with 131 comments

  • by ProfessorLayton on 12/30/19, 8:44 PM

    This looks interesting!

    A bit of a rant, but I long for a digital version of an FM transmitter. Multi-speaker playback with basically no setup and perfect sync that also fails gracefully can already be done with an FM transmitter. I would love it if there was a solution for the digital era.

    I have been forced into the bluetooth era kicking and screaming with my iPhone 11 and I constantly feel like I've taken a step back by being forced to use bluetooth. The constant pairing issues, even with Apple's AirPods (which are the most reliable by far) has been a constant pain point for me. Pairing, unpairing, and multiple device management is a UX nightmare for something as simple as audio payback.

  • by matthew-wegner on 12/30/19, 9:02 PM

    I've been running whole-home Snapcast for over a year now, controlled by Home Assistant. Some quick info:

    - Previously, I would use Raspotify/etc and automatically change sources as I moved between rooms. This is much cleaner

    - My automation server is a Linux VM, which is now my audio source for Snapcast. This means I just use the native, 100% unmodified Spotify client (or really, anything). Previously the various librespot/etc stuff would sometimes break or require updates

    - I run two streams: Music + text to speech, and just TTS. Some rooms switch to TTS-only when the room turns off. Other rooms mute completely. Really it just depends how peripheral the room is. i.e. my garage mutes completely when it's off, but more interior rooms still play TTS.

    - Pulseaudio junk is what manages the above routing. Linux audio really is gross once you try to do anything past-minimum with it. You can do complicated things, though--I duck music volume down a bit when house TTS is happening. I still have to regularly and automatically restart pulseaudio completely when nothing is playing, to avoid both horrid clock drift and/or crackle

    - Any audio you can play/handle on Linux, you can make into a stream. I could easily add a third stream for an aux-in line dangling off the machine, for people to plug in to for parties/hardware players/etc

    - Most clients are Raspberry Pis with USB audio DACs. My macOS machines also run snapclient. I only have one Windows machine (my TV box) I wanted to include, and ended up just running a Ubuntu VM with snapclient to make that happen. (The other option is to use pulseaudio in a VM, and then also an ancient Windows port of pulseaudio to actually take the pa data out to the speakers, but ugh)

    - Including all computers, I have 8 clients, I think? You can enable "send audio to muted clients" to avoid a re-buffer delay when rooms turn on and off

    - You can push latency quite low if you want, especially if everything in your house is hardwired. My desktop audio is almost always Spotify now, out of laziness, and really when I'm using the desktop client I'm actually controlling the remotely-playing VM. The latency doesn't bother me, and I'm pretty sensitive to that kind of thing

    - I use cheap 10-button RF remotes as "light switches" in all rooms. It's nice to have that many buttons to standardize some things. For music, two buttons are play/stop spotify, with some overloaded functions (pressing play while music is already playing skips to next track)

  • by jrobn on 12/30/19, 8:11 PM

    I have an extensive sonos setup for my business. I’ve experienced a lot of trouble with the system just cutting out, skipping tracks over and over, and connecting to Apple Music. Every couple of weeks it just totally shits the bed.

    Would love speakers that could serve music off my Synology NAS reliably and without microphones in my speakers to spy on me.

    With the whole google/nest fiasco I don’t want to actively try to thwart a speaker from collecting data on me and my family. It’s exhausting.

    Someone needs to start a company, like, Elgato Eve, where their primary feature product is privacy focused products. They would have my money every time.

  • by geekuillaume on 12/29/19, 10:10 AM

    Not my project but I've been using it for a year on 3 Raspberry Pi and it has been rock solid. I highly recommend it. The synchronization is perfect and it only adds a small delay (500ms max) to the music. I've configured Librespot to use this as a Spotify Play speaker and control it from the desktop or mobile Spotify app.

  • by reggieband on 12/30/19, 8:54 PM

    > The encoded chunk is sent via a TCP connection to the Snapclients.

    I wonder why TCP? For streaming media I would expect UDP, RTP or even RTMP to be better. Maybe even something newer like QUIC.

    edit: in fact, isn't RTP/RTCP made for exactly this purpose? The streaming/synchronization of media?

  • by thomas536 on 12/30/19, 8:58 PM

    There has also been some work on low latency audio this year via https://gavv.github.io/articles/roc-tutorial/

  • by milesward on 12/30/19, 8:23 PM

    Now what we need is a method to hijack the phone-home process new Sonos devices use, and have them controlled via this. It's amazing to me how glitchy and fragile the native Sonos network is. I have lots of zones, but wow.

  • by genericacct on 12/31/19, 4:13 AM

  • by federico3 on 12/30/19, 8:31 PM

    I always wondered why there aren't synchronous "audio conferencing" tools to allow play music and even improvise over the Internet.

    Of course they would have to introduce a fixed delay of a phrase (or multiple) and people would have to play accordingly.

  • by mr_sturd on 12/30/19, 8:24 PM

    Got two Raspberry Pi with HiFi Berry HATs, and have been trying to use RTP over Pulseaudio, from my home server, but have never managed to get the synchronisation right.

    I'll be starring this project and giving it a go as soon as possible. Can't wait!

  • by toomim on 12/30/19, 11:05 PM

    This looks cool! Has anyone used it with Airplay? Can you report on how well it works?

    I'd love to be able to stream from laptops and phones -- without installing additional software on them.

  • by hippich on 12/31/19, 4:25 AM

    Any1 aware of any solutions to stream (let's say through pulseaudio) realtime audio? I.e. matching what happens on the screen. Is it even possible?

  • by jakobegger on 12/31/19, 10:47 AM

    Can someone explain why I would use this over Shairport Sync [1]? Setting up shairport is so easy, and it works great with iPhones and Macs as audio sources (which happens to be what I use).

    Is Snapcast just more compatible with Linux clients, or are there any other advantages?

    [1]: https://github.com/mikebrady/shairport-sync

  • by amflare on 12/30/19, 10:19 PM

    I've just started getting into Sonos because I want the full house audio, but I'm not sold yet. The worry I have with Snapcast is that sometimes it's worth the money for things to JustWork(tm). I know Sonos is super janky sometimes, but at least I don't have to build it from the ground up with a patchwork of technologies across my various computers and phone

  • by mongol on 12/30/19, 9:58 PM

    I use this in three ways: To stream from MPD, to stream from a DLNA renderer (gmrender-resurrect) and to stream from Pulseaudio. It is generally great, but the audio from Pulseaudio is not working well, quality-wise. The one remaining problem is sometimes that podcasts that I stream via DLNA plays much too fast. Seems to depend on circumstances in the podcast stream.

  • by fizixer on 12/30/19, 6:50 PM

    I can't see any info of what clients are supported. I'm interested in serving audio to both "speaker clients" as well as mobile-app clients.

    For mobile setup, I currently use soundwire (it has an android app as a client, and I serve audio from a linux server) but the sync is not very good.

  • by paul7986 on 12/31/19, 12:00 AM

    Out of the box Does this support syncing audio from web streams like YouTube?

    Also, is this trivial to set up and is there a web app I can use to test it out?

  • by ww520 on 12/31/19, 7:56 AM

    The project looks good. Would multicast be good for this kind of applications? How much support do routers have for multicast these days?

  • by Ice_cream_suit on 12/30/19, 10:39 PM

    How long before Snapchat's lawyers send a letter, insisting that the name be changed to something less misleading?

  • by brayhite on 12/30/19, 7:23 PM

    How does this compare to something like Airfoil?

  • by RosanaAnaDana on 12/30/19, 7:13 PM

    I'm so excited to try this.