Airfoil

Airfoil" primarily refers to a popular, professional-grade audio streaming application for macOS (and formerly Windows), developed by Rogue Amoeba.

It solves a common limitation in many operating systems by allowing you to stream any audio playing on your computer to multiple, heterogeneous wireless outputs simultaneously, with perfect synchronization.

Core Functionality

Airfoil's main purpose is to act as a universal transmitter for audio on your network:

1. Any Audio Source: You can select a specific application (like Spotify, YouTube in a browser, VLC, or a game) or even your entire system audio as the source.

2. Multiple Protocols: It streams this audio simultaneously to devices using different wireless protocols:

   • AirPlay: Apple TV, HomePod, AirPort Express, and third-party AirPlay speakers (Bose, Sonos, etc.).

   • Google Cast: Google Chromecast, Google Home speakers, and Cast-enabled smart TVs.

   • Bluetooth: Standard Bluetooth speakers and headphones.

3. Perfect Sync: Airfoil handles all necessary buffering and latency correction to ensure that the audio plays on all connected devices at the exact same moment.

4. Airfoil Satellite: This is a free companion app (available for Mac, Windows, iOS, and Android) that turns that specific device into an Airfoil receiver, expanding your network to include other computers, phones, and tablets.

Key Features

• Source Selection: Stream only the audio from a single application, leaving system alerts and other sounds on your Mac's internal speakers.

• Speaker Groups: Create saved groups of outputs (e.g., "Living Room Zone" or "Whole House") to connect with a single click.

• Metadata & Remote Control: For compatible sources (like Apple Music or Spotify), Airfoil sends track titles and album art, and allows you to remotely control playback (play/pause, skip) from an Airfoil Satellite device.

• Built-in Equalizer: Tweak the sound quality before it is transmitted