BabelPod

A modern audio routing system that connects various inputs (Line-in, Bluetooth, PCM) to different outputs (AirPlay speakers including HomePod, Bluetooth devices, PCM outputs). Built with cross-platform support and a modern React frontend.

Features

Audio Routing

• Multiple Input Types:
  • Line-in audio sources
  • Bluetooth devices
  • PCM audio devices
  • Virtual/void devices
• Multiple Output Types:
  • AirPlay speakers (including HomePod)
  • Bluetooth audio devices
  • PCM audio outputs
  • Multiple simultaneous outputs

Modern Interface

• Real-time device discovery and connection
• Individual volume controls per device
• Device grouping support
• Audio preset support
• Dark mode interface optimized for touch screens
• Responsive design
• Real-time status updates

Technical Features

• Cross-platform support (Linux and macOS)
• Native audio integration
• Low latency audio routing
• Automatic device discovery
• Graceful fallbacks for unsupported features
• TypeScript throughout
• Modern React patterns
• Socket.IO for real-time updates

Prerequisites

For Raspberry Pi (Raspbian):

1. Install required packages:

# Audio and Bluetooth dependencies
sudo apt-get update
sudo apt-get install -y bluez pulseaudio-module-bluetooth
sudo apt-get install -y libasound2-dev avahi-daemon

2. Configure Bluetooth service permissions:

# Create a new policy file
sudo nano /etc/polkit-1/localauthority/50-local.d/46-allow-bluetooth-service.pkla

Add this content:

[Allow users to manage bluetooth service]
Identity=unix-group:bluetooth
Action=org.freedesktop.systemd1.manage-units;org.freedesktop.systemd1.manage-unit-files
ResultAny=yes
ResultInactive=yes
ResultActive=yes

3. Set up user permissions:

# Create bluetooth group and add your user
sudo usermod -aG bluetooth $USER

# Add user to audio group
sudo usermod -aG audio $USER

4. Configure Bluetooth settings:

sudo nano /etc/bluetooth/main.conf

Add these lines:

[Policy]
AutoEnable=true

[General]
ControllerMode = bredr

5. Apply changes:

# Restart Bluetooth service
sudo systemctl restart bluetooth

# Reboot to apply all changes
sudo reboot

For Other Linux Distributions:

1. Install required packages:

# Audio and Bluetooth dependencies
sudo apt-get install bluez pulseaudio-module-bluetooth
sudo apt-get install libasound2-dev avahi-daemon

2. Configure Bluetooth permissions:

# Create a new polkit rule file
sudo nano /etc/polkit-1/rules.d/51-bluetooth.rules

Add this content:

polkit.addRule(function(action, subject) {
    if ((action.id == "org.bluez.device.pair" ||
         action.id == "org.bluez.device.connect" ||
         action.id == "org.bluez.device.disconnect" ||
         action.id == "org.bluez.adapter.discoverable" ||
         action.id == "org.bluez.adapter.bondable" ||
         action.id == "org.bluez.adapter.blocked") &&
        subject.local && subject.active && subject.isInGroup("bluetooth")) {
            return polkit.Result.YES;
    }
});

3. Set up user permissions:

# Create bluetooth group and add your user
sudo groupadd -f bluetooth
sudo usermod -aG bluetooth $USER

# Add user to audio group
sudo usermod -aG audio $USER

4. Configure Bluetooth settings:

sudo nano /etc/bluetooth/main.conf

Add these lines:

[Policy]
AutoEnable=true

[General]
ControllerMode = bredr

5. Apply changes:

# Restart Bluetooth service
sudo systemctl restart bluetooth

# Log out and log back in for group changes to take effect

For macOS:

# Install required utilities
brew install blueutil switchaudio-osx sox

Installation

1. Clone the repository:

git clone https://github.com/gsperry/babelpod.git
cd babelpod

2. Install Node.js dependencies:

npm install

3. Build the application:

npm run build

4. Start the server:

npm start

The web interface will be available at http://localhost:3000

Development

To run in development mode with hot reloading:

npm run dev

This will start both the backend server and frontend development server.

Architecture

Frontend

• React with TypeScript
• Tailwind CSS for styling
• Socket.IO for real-time communication
• shadcn/ui for component library

Backend

• Node.js with Express
• Socket.IO for real-time communication
• Platform-specific audio integrations:
  • Linux: ALSA, PulseAudio, BlueZ
  • macOS: CoreAudio, BlueUtil

Audio Routing

• AirPlay: node_airtunes2
• PCM: Platform-specific implementations
• Bluetooth: Platform-specific implementations with fallbacks

Platform Support

Linux

• Full support for all features
• Uses native ALSA and PulseAudio
• D-Bus for Bluetooth (with command-line fallback)
• AirPlay support via node_airtunes2

macOS

• AirPlay support
• Native Bluetooth support
• CoreAudio integration
• Some features may require additional permissions

Contributing

Contributions are welcome! Please read CONTRIBUTING.md for details on our code of conduct and the process for submitting pull requests.

Authors

• Guy Sperry - Modern rewrite, Bluetooth support, cross-platform compatibility
• Andrew Faden - Original creator

License

This project is licensed under the MIT License - see the LICENSE.md file for details.

Acknowledgments

• Original BabelPod project by Andrew Faden
• node_airtunes2 for AirPlay functionality
• shadcn/ui for React components
• Tailwind CSS for styling
• Socket.IO for real-time communication

Screenshots