• Tech Tips

    Using OBS and Blackhole as an Audio Router

    I’ve been having a difficult timing capturing aggregate audio from my Shure MV7 microphone and my system audio. After trying the BlackHole + Audio Midi Setup unsuccessfully I found some information about how to use OBS Studio + BlackHole to configure, monitor, and send audio from many sources into a single output.

    Using this configuration I’m able to record, transcribe, etc. all of this audio as if it were a single input source. An added bonus is that I can monitor the input, adjust levels, etc. from the OBS Studio user interface.

    For what it’s worth, this entire process seems to work exactly the same with the VB-CABLE Virtual Audio Device. Just use VB-CABLE instead of BlackHole 16ch in steps 3 and 5 below.

    Step 1: Install Blackhole ( brew install blackhole-16ch )

    Step 2: Install OBS Studio

    Step 3: Open OBS Studio’s Settings. Set Audio ➙ Advanced ➙ Monitoring Device to BlackHole 16ch

    Step 4: Add macOS Audio Capture sources to OBS Studio and configure each to use Monitor and Output (monitor is the important piece). In the example below I’m getting audio from my mic and two specific applications (Chrome and Zoom).

    Step 5: Use BlackHole 16ch as the “microphone” or “input” in the app of your choosing (audio recorder, transcription tool, etc.)

    OBS Studio settings

    Bonus Tip

    What if you want to control your microphone output to Zoom (or whatever) from within OBS Studio? You can use a second virtual audio device! Using the OBS Audio Monitor plugin you can route the actual audio “Output” from OBS Studio to whatever device you choose. The “Audio Mixer” dock controls the output to BlackHole (via the “Monitor Only” setting and corresponding Monitor -> BlackHole 16ch application setting), and the Audio Monitor dock controls output to VB-CABLE (via the “Monitor and Output” setting).

    OBS Studio Audio Monitoring

    Advanced audio properties

    1. Install the VB-CABLE virtual audio device
    2. Install the OBS Audio Monitor plugin
    3. Enable the Audio Monitor dock
    4. Configure the output to go to VB-CABLE
    5. In whichever apps you’d like, use VB-CABLE as the “Microphone” (input) instead of your actual microphone.
    6. Make sure only your microphone is set to “Monitor and Output”
    7. If desired, you can set a hotkey to mute/unmute your microphone via Settings ➙ Hotkeys ➙ Shure MV7 in (for example)
      1. You can set the same hotkey to both mute and unmute, and it’s a universal hotkey that is available even if OBS isn’t the front window.

    Bonus Bonus Tip

    One more for ya! Enabling the Waveform plugin in the preview area is a great way to have a visual reminder when your microphone is “hot.”

    After disabling all of the unneeded docks here’s what I’m left with:

    Waveform

    You can even add additional waveforms for your other input sources:

    Additional input sources