Loopback

Loopback is an essential audio routing application for macOS developed by Rogue Amoeba. It's often described as a "virtual audio patch bay" because it allows you to create custom, cable-free ways for audio to flow between different applications and physical audio devices on your Mac.

Here is a breakdown of its features, use cases, and technical details:

Core Functionality: Virtual Audio Devices

Loopback's primary function is to let you combine multiple audio sources—like a microphone, an audio interface, and the sound from multiple running applications—into a single, unified Virtual Audio Device.

1. Creation: You use Loopback's interface to select your sources (e.g., Spotify, Chrome, your USB Mic).

2. Combination: Loopback mixes these sources together in real-time.

3. Routing: The resulting Virtual Audio Device then appears as a normal input or output device in your Mac's system settings and in any audio application (Zoom, OBS, GarageBand, etc.).

This solves a common Mac issue where applications only allow you to select one audio input at a time.

Key Use Cases

Loopback is indispensable for content creators, streamers, and remote workers:

• Podcasting & Video Calls: Send your mic audio and background music or sound effects (from another app like Farrago or QuickTime) as a single, perfectly mixed source to your co-hosts or guests on Zoom, Discord, or Skype.

• Live Streaming: Route game audio or screen-capture audio along with your voice commentary to streaming software like OBS, ensuring your audience hears everything cleanly.

• DAW/Recording: Record audio from an application (like a web browser or a non-ASIO/Core Audio app) directly into a Digital Audio Workstation (DAW) like Logic Pro or Ableton Live.

• Monitoring & Pass-Thru: Create simple pass-thru devices to send audio directly from the output of one application (e.g., Logic Pro) straight into the input of another (e.g., an audio analysis tool) for monitoring or testing.