How to Separate Audio Sources in OBS on Mac — Mic, Desktop, and Game Audio

If you've ever recorded a gaming session or tutorial in OBS and realized your mic, game audio, and desktop notifications are all fused into a single indistinguishable blob of sound — welcome to the most fixable rookie mistake in video production. Everything baked together into one track feels fine until you sit down to edit and realize you can't remove that Slack ding without cutting out your voice too.

The fix is straightforward: route each audio source to its own track before you hit record. On Windows this is relatively painless. On Mac it takes one extra step because macOS deliberately blocks apps from capturing system audio without a workaround. This guide walks through both the Mac-specific audio routing setup and the OBS configuration to make multi-track recording work. By the end, your mic, desktop audio, and game audio will each live on their own lane — and your editor will thank you.

Why Separate Audio Sources Matter

When you record with a single mixed track, every edit decision becomes destructive. You want to pull down the background music during a quiet moment — you're also pulling down your voice. You want to strip out the notification sound at 4:23 — good luck surgical-cutting that out of a stereo mix where it overlaps your commentary. The audio is baked, and baked audio is uneditable audio.

Separate tracks solve this completely. With mic on Track 1 and desktop audio on Track 2, you can mute music without touching narration. You can apply noise removal to just your mic without altering game audio. You can conform the levels of each source independently in post without fighting bleed. For YouTube creators especially, this matters doubly: a copyright claim on background music in a single-track recording can demonetize the whole video. With separate tracks, you can silence or swap the offending audio before upload without re-recording a thing.

The editorial flexibility you gain from this setup is the difference between footage you can actually work with and footage you're stuck hoping sounds okay enough to ship as-is.

The Mac Audio Problem

On Windows, OBS can grab desktop audio directly via a system hook — apps like Voicemeeter and Win Capture Audio extend this with per-application routing. It just works. Mac is different by design: macOS does not expose a system-level audio tap to third-party apps. There's no "Desktop Audio" source in OBS on Mac the same way there is on Windows. If you add a standard Audio Input Capture in OBS on a Mac and browse the source list, you'll see your microphone and any connected USB/Bluetooth devices — but no system output.

This isn't an OBS bug. It's a macOS privacy decision. To get internal audio into OBS on Mac, you need a virtual audio device that sits between macOS's output and OBS's input — a software cable that reroutes the signal. There are a few options: BlackHole (free, open-source), Loopback by Rogue Amoeba (paid, more GUI-friendly), and the now-discontinued SoundFlower. BlackHole is the most reliable free option and the one this guide uses.

Installing BlackHole on Mac

BlackHole is a free, open-source virtual audio driver from Existential Audio. It installs a virtual audio device that macOS treats like a real output — but anything routed to it also appears as an input, which is exactly what OBS needs. Installation takes about five minutes.

1. Download BlackHole from existential.audio/blackhole. The 2ch version is sufficient for OBS audio capture.
2. Run the installer and follow the prompts. You may need to allow the kernel extension in System Preferences → Security & Privacy → General.
3. Open Audio MIDI Setup (find it via Spotlight or in /Applications/Utilities/).
4. Create a Multi-Output Device: click the + button at the bottom left, choose "Create Multi-Output Device." Check both "BlackHole 2ch" and your normal output (Built-in Output or your headphones/speakers). This lets audio play through your speakers while simultaneously routing a copy to BlackHole.
5. Set the Multi-Output Device as your system output: go to System Preferences → Sound → Output and select the Multi-Output Device you just created.

Now your Mac's audio plays normally through your speakers, but a copy of everything is simultaneously flowing into BlackHole — which OBS can read as an audio input source.

OBS Audio Mixer Setup

With BlackHole installed and the Multi-Output Device active, open OBS and head to your Sources panel. You need two audio sources: your microphone and BlackHole (as desktop audio). Add an Audio Input Capture source for your mic — name it "Mic" so it's easy to find in the mixer. Add a second Audio Input Capture source and select "BlackHole 2ch" — name it "Desktop Audio."

Confirm both appear in the Audio Mixer at the bottom of OBS and that the level meters move when you speak and when audio plays on your Mac. If Desktop Audio isn't moving, double-check that the Multi-Output Device is set as your system output and that BlackHole 2ch is included in it.

Now assign each source to a separate track. Right-click your Mic source in the mixer and choose "Advanced Audio Properties" (or access it via Edit → Advanced Audio Properties). In that dialog, you'll see track checkboxes (Track 1 through Track 6) for each source. Assign Mic to Track 1 only. Assign Desktop Audio to Track 2 only. This is the critical step — without it, both sources are mixed down to Track 1 and you're back to the single-track problem.

If you're recording game audio from a specific game window rather than all desktop audio, you can add a third source for that and route it to Track 3. The same principle applies: one source, one track, maximum editing flexibility.

Recording with Multiple Tracks

Assigning sources to tracks in Advanced Audio Properties is only half the job. OBS also needs to be told to actually record those tracks to the output file — by default it may only write Track 1.

Go to Settings → Output and make sure you're in "Advanced" output mode (not Simple). Under the Recording tab, look for the "Audio Track" checkboxes. Enable Track 1, Track 2, and any additional tracks you've set up. The recording format matters here too: MP4 merges tracks into a single interleaved file, while MKV preserves them as discrete streams. For multi-track editing, MKV is more reliable — you can always remux to MP4 after the fact with no quality loss using OBS's built-in remux tool (File → Remux Recordings).

Do a short test recording before a real session. Play some audio on your Mac, speak into your mic, then check the output file in your editor. You should see at least two audio tracks in the timeline — if you only see one, revisit the Advanced Audio Properties assignments and the Output track checkboxes.

Editing Multi-Track Audio

Once you have a recording with separate audio tracks, your editing options open up significantly. The three most common editors handle it slightly differently.

DaVinci Resolve natively reads multi-track MKV and MP4 files. When you drop the clip into the timeline, it expands into separate audio tracks per stream. You can apply effects, EQ, and noise removal to each independently. The Fairlight audio page gives you full per-track mixing control — this is the professional path if you're doing serious audio post.

Final Cut Pro also handles multi-track recordings well. Import the clip and choose "Expand Audio to Separate Lanes" from the right-click menu or the Clip menu. Each OBS track becomes its own lane in the timeline. You can apply roles, adjust levels independently, and export with custom audio channel assignments.

Descript is worth mentioning for creators who want a faster workflow. It reads multi-track recordings and lets you edit by transcript — useful for tutorials and talking-head content where you want to cut based on what was said, not waveform shapes. The separate tracks mean you can apply Studio Sound (AI noise removal) to just the mic track without processing game audio through it.

Windows Alternative: Voicemeeter

If you're on Windows, the BlackHole approach doesn't apply — but the multi-track goal is the same. The Windows equivalent is Voicemeeter (free) by VB-Audio, which acts as a virtual audio mixer. You route your applications' outputs through Voicemeeter's virtual inputs, assign them to separate output buses, and then bring those buses into OBS as separate audio sources. Win Capture Audio (a community OBS plugin) extends this further by letting you capture audio from specific Windows applications without routing everything through a system-level virtual device.

The OBS configuration steps after that — Advanced Audio Properties, track assignments, enabling multi-track output in Settings — are identical to Mac. The platform difference is only in how you get the audio into OBS in the first place. For a deeper look at the full Windows setup with Voicemeeter, the video above covers both platforms side by side.

Related reading: OBS on Mac: Full Screen Recording Setup Guide · AI Video Editing for Short-Form Content