I built a per-app audio mixer for macOS as a solo dev

Ian — Sun, 01 Mar 2026 14:11:50 +0000

macOS doesn't have per-app volume control. It's had one volume slider since forever. Windows has had per-app audio since Vista. I finally got annoyed enough to build my own.

What I built

SoundPrism is a menu bar app that gives you individual volume, EQ, compression, and output routing for each app running on your Mac. It also allows you to record audio per app, either dry, wet or both at once!

There are two ways to use it. A quick popover from the menu bar handles volume, mute, and basic EQ.

Hit ⌘⇧C and you get a full mixing console with channel strips, VU meters, EQ curves, and compressor metering for every app.

Some engineering details

The whole thing is Swift, built on native Apple audio frameworks. No kernel extensions, no third-party audio drivers.

Each app runs through a real-time DSP chain:

10-band biquad IIR equalizer
3-band multiband compressor (Linkwitz-Riley crossovers)
Brick-wall peak limiter
Stereo widener and crossfeed processor
Everything on the audio thread is lock-free. Zero allocations, zero locks.

Pricing and launch

7-day free trial, $24.99 one-time. No subscriptions.

I launched it yesterday on Product Hunt and I'm posting it here to see what other devs think.

https://castorlogic.com/soundprism

I'm happy to answer questions about the implementation, the DSP chain, or the experience of launching a paid macOS app as a solo developer.

DEV Community: Ian

I built a per-app audio mixer for macOS as a solo dev