Home Automation, part 3 - Multi room music and sound system with Mopidy and Snapcast

Context

In the previous [[][home automation blog post]], I explained how I installed the central pieces of my [[][home automation]] system ([[][NodeRed]], [[][Mosquitto]] and [[][Domoticz]]). Before starting explaining some of the flows, routine and automation, I need to finish explaining the global setup. This post is about my setup for my music server ([[][Mopidy]]) and the multi room sound system ([[][Snapcast]]).

You can find the full architecture defined in this [[][post]], but the TLDR; is this image (updated from previous post):

Figure 1: My Home Automation architecture

As shown in the diagram above, my setup is composed of:

• A raspberry pi (brook¹) in the kitchen, running snapcast server (snapserver), Mopidy and Snapcast client (snapclient) with a cheap USB speaker (as I just need basic sound while I’m cooking).
• A raspberry pi (ryo saeba²) running snapcast client (snapclient) with the same cheap USB speaker (mainly used in the morning for my alarm routine)
• My laptop (in the office), running snapcast client (off by default), connected to a bluetooth speaker (off by default too)

I’m using cheap USB speakers mainly because I bought them as a proof of concept (12€ each) to validate the possibility. I’m thinking of changing the one in my bedroom (I don’t care about sound quality in the kitchen). Aside from the sound quality, this system has been working smoothly with almost no issues for at least a year :).

I also need to add a snapclient in my living room plugged to my soundbar as well. But I still need to work on it. The good news is that adding a snapcast client is damn easy :).

Installation and Configuration of Snapcast and Mopidy

Mopidy

Installation

Simply follow the official raspberry pi install documentation (Use a dedicated mopidy user!).

For the installation itself:

    wget -q -O - https://apt.mopidy.com/mopidy.gpg | sudo apt-key add -
    sudo wget -q -O /etc/apt/sources.list.d/mopidy.list https://apt.mopidy.com/buster.list
    sudo apt update
    sudo apt install mopidy mopidy-mpd mopidy-spotify

Configuration

See the official documentation for options and configuration! In the meantime, this is my /etc/mopidy/mopidy.conf:

    [core]
    #cache_dir = $XDG_CACHE_DIR/mopidy
    #config_dir = $XDG_CONFIG_DIR/mopidy
    #data_dir = $XDG_DATA_DIR/mopidy
    #max_tracklist_length = 10000
    #restore_state = false

    [logging]
    color = true
    console_format = %(levelname)-8s %(message)s
    debug_format = %(levelname)-8s %(asctime)s [%(process)d:%(threadName)s] %(name)s\n  %(message)s
    debug_file = mopidy.log
    config_file = logging.conf

    [audio]
    # We will understand that later. Leave commented for now!
    # output = audioresample ! audioconvert ! audio/x-raw,rate=48000,channels=2,format=S16LE ! wavenc ! filesink location=/tmp/snapfifo

    [mpd]
    enabled = true
    hostname = 0.0.0.0
    port = <port>
    #password =
    max_connections = 5
    connection_timeout = 60
    #zeroconf = Mopidy MPD server on $hostname
    #command_blacklist =
    #  listall
    #  listallinfo
    default_playlist_scheme = m3u

    [http]
    #enabled = true
    #hostname = 127.0.0.1
    #port = 6680
    #static_dir =
    #zeroconf = Mopidy HTTP server on $hostname

    [m3u]
    enabled = true
    #base_dir =
    #default_encoding = latin-1
    #default_extension = .m3u8
    #playlists_dir =

    [softwaremixer]
    #enabled = true

    [file]
    # I don't have local music files.
    enabled = false

    [local]
    # I don't have local music files.
    enabled = false

    [spotify]
    enabled = true
    username = <username> # Changeme
    #password = <password> # Changeme
    client_id = <spotify-client-id> # Changeme
    client_secret = <spotify-client-secret> # Changeme
    bitrate = 320
    volume_normalization = true
    private_session = false
    timeout = 20
    allow_cache = true
    allow_network = true
    allow_playlists = true
    search_album_count = 20
    search_artist_count = 10
    search_track_count = 50
    toplist_countries =

    [spotify_web]
    client_id = <spotify-client-id> # Changeme
    client_secret = <spotify-client-secret> # Changeme

    [tunein]
    enabled = false

    [http]
    enabled = true
    hostname = ::
    port = <port> # Changeme
    static_dir =
    zeroconf = brook

    [mopify]
    enabled = true
    debug = false

    [musicbox_webclient]
    enabled = true
    musicbox = false
    websocket_host =
    websocket_port =
    on_track_click = PLAY_ALL

The important piece for me are the activation of the [[][MPD]] deamon (the [mpd] section) so mopidy can be used with any MPD client (for my laptop) and is connected to spotify for my music library (see [spotify] section).

Control

• Web UI

  I enabled 2 Web UI: [[][musicbox]] and [[][mopify]]. If you want to have web UI, you need to enable http extension (see above my config file or the official documentation).

  If you want to use them, you’ll have to install them.

  For Mopify:

      sudo pip3 install Mopidy-Mopify
  

  For MusicBox Webclient:

      sudo pip3 install Mopidy-MusicBox-Webclient
  

  Then go to http://<MopidyServerIpAddress>:<port>/mopidy (<port> is the one defined in the [http] section), and you’ll be asked to choose between mopify and music box.

  Check the documentation for more Web UI or extension!

• MPD client

  As I have enabled Mopidy to act as a MPD deamon, I can use any MPD client to control it. For example, I’m using ncmpcpp on my laptop (because TUI FTW! :)), but you could use any mpd client!

• Mobile App

  There is a great Mopidy android application :-).

Playing sound.

At this point, you should be able to play music with Mopidy through any of the client, eg by going to the web UI. Be careful, for now the sound will only play on the machine where mopidy is installed and not on the client machine! Once the music works, let’s move on the snapcast configuration to send the sound to the right places!

Snapcast

[[][Snapcast]] is a Synchronous multiroom audio player. It means it can manage multiple clients that will play music in a synchronous manner (= no lag on the different clients). It is really simple yet powerful as you can manage the different client volume level and you can even have multiple stream if you want to play different music in the different rooms. This is planned on my todolist, but for now I’m using only 1 stream so all rooms will play the same thing (if they are not muted of course).

Installation

First, we need to install the snapcast server (snapserver), so on the server you want to run snapserver:

Go to the latest release page, and copy the link to the armhf deb:

    wget "https://github.com/badaix/snapcast/releases/download/v0.19.0/snapserver_0.19.0-1_armhf.deb"  # May change in case of new release.
    sudo dpkg -i snapserver_0.19.0-1_armhf.deb
    sudo apt -f install # To fix dependencies

Then, on each machine where you want to install snapclient³:

On my Raspberry Pi (brook and nickylarson):

    wget "https://github.com/badaix/snapcast/releases/download/v0.19.0/snapclient_0.19.0-1_armhf.deb" # May change in case of new release
    sudo dpkg -i snapclient_0.19.0-1_armhf.deb
    sudo apt -f install

And then on my laptop (running ubuntu for work related reasons):

    wget "https://github.com/badaix/snapcast/releases/download/v0.19.0/snapclient_0.19.0-1_amd64.deb" # May change in case of new release
    sudo dpkg -i snapclient_0.19.0-1_amd64.deb
    sudo apt -f install
    sudo systemctl disable snapclient # To not start it automatically.

Look at the official documentation if you don’t use a raspberry pi or want more information.

Configuration

• Snapserver

  Edit the configuration file /etc/default/snapserver (defines snapserver command arguments):

      START_SNAPSERVER=true
      SNAPSERVER_OPTS=""
  

  The configuration is very simple because I only use one stream, so I don’t need to declare anything specific here. I just set snapserver to start by default

  Then edit the server configuration /etc/snapserver.conf. I’m going to only highlight here the changed values:

      [http]
      #enable HTTP Json RPC (HTTP POST and websockets)
      enabled = true
  
      # use "0.0.0.0" to bind to any IPv4 address or :: to bind to any IPv6 address
      bind_to_address = 0.0.0.0
  
      # which port the server should listen to
      port = <port> # changeme
  
      [tcp]
      # enable TCP Json RPC
      enabled = true
  
      # use "0.0.0.0" to bind to any IPv4 address or :: to bind to any IPv6 address
      bind_to_address = 0.0.0.0
  
      # which port the server shgould listen to
      port = <port2>
  
      stream = pipe:///tmp/snapfifo?name=default
  

  The stream = pipe:///tmp/snapfifo?name=default line is very important, it should remind you of a commented line in our mopidy.conf file that you need to uncomment now:

      output = audioresample ! audioconvert ! audio/x-raw,rate=48000,channels=2,format=S16LE ! wavenc ! filesink location=/tmp/snapfifo
  

  The location=/tmp/snapfifo is the way to tell Mopidy to use snapcast as audio output. See the documentation for more information.

  I also enabled the [http] section to be able to send JSON-RPC request via http from NodeRed, but more on that later :).

• Snapclient

  Edit the configuration file /etc/default/snapclient on each snapclient⁴:

      START_SNAPCLIENT=true
      SNAPCLIENT_OPTS="-s 15"
  

  The -s 15 is to indicate snapclient to use the 15 soundcard. To find the right soundcard you can run snapclient -l to get the list with their id.

Control

• Mobile App

  Snapcast provides a very minimalist android application to control snapcast client volume level. The android app can also be downloaded on the release page. The app is called snapdroid and can be found on the play store or on the [[][snapdroid release page]].

• JSON-RPC API

  Snapcast provides a full [[][JSON-RPC API]] that can be leverage to control it. I’m mainly using through my home automation brain [[][NodeRed]], but we will see this in another post :).

And now what?

Now, you should have a working Mopidy server, connected to your spotify account that you can control through any device and client. When playing music via a mopidy client (web, mpd, mobile app), sound will be played through snapcast on the different enabled clients (check on the android app the volume level of each and the mute status ;)).

Conclusion

We’ll see in later post how to manipulate and integrate this sound system in the more global home automation by configuring some NodeRed flows (via MPD for Mopidy and Json-RPC for snapcast) :)

Just to whet your appetite, this is part of my dashboard to control (part of) the sound system:

Figure 2: Sound and Music dashboard