Levels vs Background Music: free per-app volume apps for Mac
Background Music and Levels are both free, open source menu bar apps that add per-app volume to macOS. They solve the problem in different ways, and that difference mostly decides which one suits your Mac.
How each one works
Background Music installs a virtual audio device. While it runs, that device becomes the system output: every app plays into it, and Background Music passes the sound on to your speakers with each app’s volume applied. The driver is installed with a package and stays in the system until you remove it.
Levels uses process taps, a Core Audio feature Apple added in macOS 14.2. It takes over the sound of the apps you adjust and plays it back at the volume you set. Your output device stays selected, apps you never touch play directly as usual, and nothing is installed into the system.
Side by side
| Levels | Background Music | |
|---|---|---|
| Price | Free | Free |
| License | MIT | GPL-2.0 |
| macOS | 11 or later, per-app volume on 14.2 or later | Also runs on versions before 14.2 |
| Per-app volume | Yes | Yes |
| Stereo balance per app | No | Yes |
| Pauses music when another app plays | No | Yes |
| Play on several outputs at once | Yes, from 1.4, with delays lined up | No, one output device |
| Installs an audio driver | No | Yes, a virtual audio device |
| System output while running | Stays on your device | Switches to the Background Music device |
Which one to pick
Background Music makes sense on a Mac older than macOS 14.2, where process taps do not exist. It also has two features Levels lacks: stereo balance per app and pausing your music player automatically when another app starts playing.
On macOS 14.2 or later, Levels gives you per-app volume and mute without an audio driver and without changing your output device. Since version 1.4 it can also play on several outputs in sync, for example the Mac’s speakers and a TV. Removing it is just deleting the app.
Sources
Details about Background Music come from its GitHub repository and release notes. For the paid option, see Levels vs SoundSource.