Routing Mac audio without SoundPipe

BlackHole is the definitive open-source replacement for those of us tired of paying for Rogue Amoeba products or dealing with the instability of older virtual drivers. If you've ever tried to route your browser audio into an AI transcription tool, a DAW, or a streaming app on macOS, you know the system is intentionally restrictive. BlackHole solves this by creating a virtual audio device that acts as a bridge: whatever goes into the "output" of the virtual driver is immediately available as an "input" for another app.

Unlike some bloated alternatives, this is a lightweight driver. It doesn't have a fancy GUI because it doesn't need one; it lives in your system settings. The real power comes when you pair it with the built-in "Audio MIDI Setup" app on your Mac.

To get this running, I recommend using Homebrew to avoid hunting for .pkg files:

brew install blackhole-2ch

Once installed, you'll see "BlackHole" as an option in your Sound settings. But here is the part where most people get stuck: if you route your system output to BlackHole, you stop hearing your own audio because the sound is being sent to the virtual bridge, not your speakers.

The fix is creating a Multi-Output Device. Open "Audio MIDI Setup," click the + icon at the bottom left, and select "Create Multi-Output Device." Check both your actual headphones/speakers and BlackHole. Now, set your system output to this new Multi-Output Device. Your audio now flows to your ears and the virtual driver simultaneously.

Is it actually worth the setup hassle?

Absolutely, especially for AI workflows. If you are running local LLMs with voice capabilities or using tools like Whisper for real-time analysis of a Zoom call or a YouTube video, this is the only way to feed the audio stream directly into the software without using a physical loopback cable or a noisy microphone.

A few caveats to keep in mind:

• Latency: It is nearly zero, but if you're doing professional music production, you might notice a tiny drift over several hours.
• Configuration: You have to manually set the "Input" of your recording app to "BlackHole" and the "Output" of your source app to the Multi-Output device. It's a one-time setup, but it's not "plug and play."
• Channel Counts: The 2ch version is plenty for 99% of users. Don't bother with the 16ch or 64ch versions unless you're routing complex MIDI arrays.

If you're tired of the "paywall" nature of Mac audio routing, this is the most stable, transparent way to handle it. It transforms the Mac from a closed ecosystem into a flexible audio hub.