What is audio routing on a Mac, in plain English

Audio routing on a Mac means deciding where each sound goes — which app plays out of your speakers, which plays into your headset, which feeds another app for recording. It is about the path the audio takes, not how loud it is. By default macOS sends every app to one output device, so sending individual apps to different places takes extra software. This guide explains what routing actually is, the handful of pieces involved, and the plain ways to do it in 2026.

"Routing" sounds like network jargon, but the idea is simple. Picture a small mixing desk backstage: sound comes in from a few sources, and someone patches each source to wherever it needs to go — the main speakers, the monitor wedge, the recording rig. Audio routing on a Mac is that patching job, done in software. You are choosing which app's sound lands on which device.

Routing vs. volume: two different questions

People often mix these up, so it is worth pinning down. Volume is how loud something is. Routing is where it goes. They are separate controls that solve separate problems:

• A volume problem: "Spotify is drowning out my Zoom call." You want the music quieter than the call — both still on the same speakers. That is per-app volume.
• A routing problem: "I want the call in my headset but music on my desk speakers." Now you are sending two apps to two different devices. That is routing.

Some Mac tools do one, some do the other, some do both. Knowing which problem you actually have saves you from installing the wrong thing.

Why macOS makes routing hard by default

Open System Settings → Sound and you get exactly one output device selected at a time. Pick your speakers and everything plays through the speakers. Switch to AirPods and everything moves to AirPods. There is no column of apps, no "send Chrome here, send Discord there." macOS treats output as a single system-wide choice.

That is fine until you want two destinations at once — game on headphones, voice chat on speakers; a video call in a headset while a shared video plays out loud for the room. The moment you need per-app output, the built-in Sound settings run out of road, and you reach for the building blocks below.

The pieces involved (and what each one is)

Routing on a Mac is built from a few parts. You do not need all of them for every task, but these are the words that come up:

All of these live in a built-in utility called Audio MIDI Setup (in Applications → Utilities). It is where the free approach happens — and where it gets fiddly.

The free DIY way: virtual device + Audio MIDI Setup

The classic no-cost route is BlackHole, a free, open-source virtual audio driver from Existential Audio, combined with a Multi-Output Device you build yourself in Audio MIDI Setup. In broad strokes: you install BlackHole, create a Multi-Output Device that includes both BlackHole and your real speakers, point an app or the system at it, and then the receiving app (OBS, a recorder, a streaming tool) listens to BlackHole as an input.

It works, it is genuinely free, and for a fixed studio or streaming setup it is a reasonable answer. The cost is your time and patience: it is manual, the menus are cryptic, sample-rate mismatches cause silence, and there is no per-app picker — BlackHole moves whatever you send into it, not "just Discord." If your need is a one-time recording rig, fine. If it is everyday, changes-by-the-hour routing, the plumbing gets old fast.

The app way: pick an app, pick an output

Dedicated tools hide all of that. Instead of wiring virtual devices, you see your running apps and choose a destination for each. They create and manage the virtual plumbing behind the scenes. What they cost and how far they go varies:

Loopback is the powerhouse if you build genuinely complex signal graphs for a podcast or a live show — and it is priced for that. For the everyday version of routing — "send this app to my headset, keep everything else on the speakers" — you do not need a node editor. You need to point an app at a device quickly and move on.

Where Fader fits

Fader treats routing as a per-app choice you reach fast. Each app gets its own output device and its own level, and because Fader is keyboard-driven, you flip an app to your headset or nudge its volume without hunting through menus. It is not trying to be a studio routing matrix like Loopback; it is built for the common case, done in a keystroke, at $19.99 one-time rather than a subscription. If your routing is "everyday, and I want it instant," that is the trade it makes.

For the step-by-step version of the most common task, see how to send an app's audio to a different output on Mac.

Do you actually need routing, or just volume?

A quick gut check before you install anything. If every app can share the same speakers and you only wish they were at different levels, you have a volume problem, and a per-app volume tool is enough. If you need sound in two places at once — different devices for different apps — that is real routing, and you want a tool that lists outputs per app. Plenty of people think they need routing when a volume slider would do; sorting that out first is the fastest path to the setup you want.

Bottom line

Audio routing on a Mac is just deciding which app plays where. macOS gives you one system output and stops there, so anything per-app needs help. The free path — BlackHole plus a Multi-Output Device in Audio MIDI Setup — is real but manual and best for fixed setups. A dedicated app trades a few dollars for skipping all that plumbing. If your routing changes through the day and you want it in a keystroke, that is exactly the case Fader is built for.