Raspberry Pi Audio Receiver
A simple, light weight audio receiver with Bluetooth (A2DP), AirPlay, Spotify Connect and UPnP.
Features
Devices like phones, tablets and computers can play audio via this receiver.
Requirements
- Raspberry Pi with Bluetooth support (tested wth Raspberry Pi 3 and Zero W) or USB dongle
- Raspbian Buster Lite (tested with June 2019 version)
- USB or I2S Audio adapter (tested with Adafruit USB Audio Adapter, pHAT DAC, and HifiBerry DAC+)
Installation
The installation script asks whether to install each component.
sudo apt update -y
sudo apt upgrade -y
sudo apt install -y --no-install-recommends git
git clone https://github.com/nicokaiser/rpi-audio-receiver.git
cd rpi-audio-receiver
./install.sh
Basic setup
Sets hostname to e.g. airpi
, the visible device name ("pretty hostname") to AirPi
.
Bluetooth
Sets up Bluetooth, adds a simple agent that accepts every connection, and enables audio playback through BlueALSA. A udev script is installed that disables discoverability while connected.
AirPlay
Installs Shairport Sync AirPlay Audio Receiver.
You may override some of the default settings in the script using environment variables.
You could pass them directly to the script,
for instance if you want a different version:
sudo SHAIRPORT_VERSION=3.3.5 ./install.sh
Here is another example, exporting them before running the individual script to also compile using a different audio back-end:
export SHAIRPORT_VERSION=3.3.5
export SHAIRPORT_CONFIGURE="--with-stdout --with-metadata --with-avahi --with-ssl=openssl --with-soxr"
sudo ./install-shairport.sh
Spotify Connect
Installs Spotifyd, an open source Spotify client).
UPnP
Installs gmrender-resurrect UPnP Renderer.
Snapcast
Installs snapclient, the client component of the Snapcast Synchronous multi-room audio player.
/dev/zero playback
Some DACs tend to produce popping/clicking noises when switching from or to stand-by (i.e. when no sound is played). An optional aplay
service can be installed which always streams an empty bytestream to the DAC. This consumes some CPU but avoids clicks.
Read-only mode
To avoid SD card corruption when powering off, you can boot Raspbian in read-only mode. This is described by Adafruit in this tutorial and cannot be undone.
Limitations
- Only one Bluetooth device can be connected at a time, otherwise interruptions may occur.
- The device is always open, new clients can connect at any time without authentication.
- To permanently save paired devices, the Raspberry has to be switched to read-write mode (
mount -o remount,rw /
) until all devices have been paired once. - You might want to use a Bluetooth USB dongle or have the script disable Wi-Fi while connected (see
bluetooth-udev.sh
), as the BCM43438 (Raspberry Pi 3, Zero W) has severe problems with both switched on, see raspberrypi/linux/#1402.
Disclaimer
These scripts are tested and work on a current (as of the current date) Raspbian setup on Raspberry Pi. Depending on your setup (board, configuration, sound module, Bluetooth adapter) and your preferences, you might need to adjust the scripts. They are held as simple as possible and can be used as a starting point for additional adjustments.
References
- BlueALSA: Bluetooth Audio ALSA Backend
- Shairport Sync: AirPlay Audio Receiver
- Spotifyd: open source Spotify client
- gmrender-resurrect: Headless UPnP Renderer
- Snapcast: Synchronous audio player
- pivumeter: ALSA plugin for displaying VU meters on various Raspberry Pi add-ons
- Adafruit: Read-Only Raspberry Pi