Per-app audio for podcasters and editors on a Mac, without a mixing desk

You don't need a hardware mixing desk to balance and route audio while you podcast or edit on a Mac. macOS has no built-in per-app volume, but software adds it: a per-app mixer gives every app its own level and its own output, so a remote guest stays loud, editor playback sits where you want it, and Slack can't blast a ping into your monitor mix. The one distinction that trips people up is recording versus riding levels — those are separate tools, and most creators want one of each.

The problem is specific to this work. A podcaster on a Mac is usually juggling a call app for the guest, a browser tab or reference clip, a recorder, and a pile of notification apps that never shut up. An editor is flipping between a timeline in Final Cut, Premiere, or DaVinci, playback in a browser, music while they cut, and the same notification chatter. macOS routes all of it through a single master output. Turn the system down and everything ducks together; there's no native panel that says "guest at 100%, music at 25%, Slack muted." A hardware desk solves that with faders, but it's money, desk space, and cable spaghetti for a job that's entirely happening inside your Mac.

First, separate the two jobs: recording vs. balancing

This is the fork that decides which tools you need, so it's worth being blunt about it.

Recording app audio means capturing what an app plays into a file — a guest's voice from Zoom, a clip's audio, a full session mix. That's a capture job. On the Mac it's what Audio Hijack ($64 one-time, from Rogue Amoeba) is built for, and it's why virtual audio devices like BlackHole (free, open source) exist — they create a "cable" you can route an app into and record from.

Balancing app audio means setting how loud each app is while you work, and sending apps to different outputs — none of which touches a recording. That's a live per-app mixer. If you're recording a podcast, you likely want both: a capture tool for the file, and a mixer so the levels in your headphones are sane while you talk. Don't reach for a $64 recorder to solve a "Slack is too loud" problem, and don't expect a live mixer to write a WAV. Match the tool to the job.

The free way: each app's own slider, by hand

Every media and call app carries some internal volume — Zoom, browsers, VLC, music apps, most DAWs and editors. You can mix by hand: drop a call app's playback, mute a browser tab, nudge reference music down. It costs nothing and for a quiet session it's fine.

It falls apart under real production load. The sliders are scattered across a dozen windows, some sources (system alerts, notification sounds, apps with no slider) can't be touched at all, and the one moment you need to yank music down is mid-sentence with a guest — exactly when you can't go hunting through menus. It's the manual friction this whole category exists to remove.

The real fix: a per-app mixer that sits at the OS audio layer

A dedicated per-app mixer works below the apps, so it can set a level for anything that makes sound — even apps with no slider of their own — and put every app's control in one place. For a podcaster or editor that's the whole game: guest loud, playback moderate, music low, notifications capped, all recallable. The tools in this space are honest and worth knowing by name.

SoundSource ($49 one-time) is the deep option — per-app volume, per-app output, and real-time EQ and effects per app. If you want to sculpt a plosive out of a guest in real time or run a channel EQ, that's its lane, and it's very good at it. Background Music covers basic per-app levels for free. Where Fader differs isn't whether it controls per-app volume — it's how fast you reach the control while your hands are already busy cutting or talking.

Why the keyboard matters when your hands are on the work

Every mixer above can set a level. The difference you feel during a session is the number of steps to make a change. A menu-bar panel means: leave the timeline or the call, move to the menu bar, click the icon, find the row, drag, dismiss. That's five actions for a volume move you make constantly — and every one of them pulls your eyes and hands off the actual work.

Fader's bet is that the fastest controller you own is the keyboard already under your hands. You hit a toggle hotkey and the keyboard becomes a mixer — one column of keys is the guest's app, the next is your music, the next is playback — and you ride levels with letter keys without leaving your editor or your sentence. For a podcaster ducking music the instant a guest starts, or an editor riding reference-track volume against timeline playback, that's the gap between "I have a mixer installed" and "I actually use it, mid-take."

Keep notifications out of your mix

The single most common ruined take is a Slack or Mail ping landing in the monitor mix — or worse, in a capture. In a per-app mixer you give the noisy apps their own low level, or bind a mute key per app. In Fader you assign a mute hotkey per channel, so "silence Slack" and "kill notifications" are one keystroke from inside your editor, no window-hunting. If you want the reverse — alerts audible but never loud — see how to keep system alerts loud while music stays quiet on a Mac.

Routing: send apps to different outputs, no cables

The other half of a deskless setup is output routing — sending one app to a different device. Monitor a session on your headphones while a reference plays through desk speakers; keep a call in your headset while music stays on the room. macOS sets one output for everything, so per-app routing also needs software. BlackHole gives you the virtual cables to build routing by hand; Fader and SoundSource let you pick an app's output from a list. If routing is your actual need, start with how to send an app's audio to a different output on Mac.

A deskless setup that holds up under production

Put together, the software-only rig looks like this. For balancing while you work: a per-app mixer with your guest or call app, music, and playback each on their own key, and notification apps muted or capped. For capture, if you're recording: Audio Hijack or a BlackHole route into your recorder. No hardware desk, no audio interface required, and every level is recallable next session instead of re-dialed by ear. The mixer is the piece you touch every few seconds; the recorder is the piece you set once and let run.

Bottom line

You can run a clean podcast or editing session on a Mac with zero hardware — the trick is matching tools to jobs. Use a capture app (Audio Hijack, or BlackHole plus a recorder) for the file, and a live per-app mixer for the balance in your ears. SoundSource is the deep, EQ-heavy pick; Background Music is the free floor. If what you care about is moving levels the instant the session demands it — ducking music mid-sentence, muting a ping without looking — a keyboard-driven mixer is the fix, and that's exactly what Fader is built for.