Combining (aggregating) audio devices in OS X
How to get more inputs and outputs out of your Mac.
I discovered a feature in Mac OS X Snow Leopard that I have a feeling has been there for a while but I just never new about. It’s called aggregate audio.
Your Mac’s built-in audio hardware lets you record a single stereo track or two mono tracks at the same time. But the problem is that if you want to record from two separate audio devices (two USB mics, or two separate sound cards )there is no easy way to do this.
Well while poking around the Utilities \ Audio Midi Setup application on OS X Snow Leopard I found out that yes you can combine audio sources and create an “Aggregate” device. In the example below I took two USB mics (Samson CO1U and a Blue Snow Flake), and I created one aggregate input device out of the two discrete devices.
To get the rest of the story let me send you to the experts at Apple. There is an article called “How to Maximize Your Inputs with Aggregate Audio” by Joe Gore, and a follow up “Recording Your Aggregate Audio Device in GarageBand or Logic Pro”. (from the looks of this article this is not new to Snow Leopard).
Now this is NOT as easy as using software like WireTap Anywhere from Ambrosia (no this is not an ad), but it’s also not $129.00. Give it a try yourself and let me know how it works for you. I will be playing more with this for sure, and maybe we can get Don McAllister from Screencasts On Line to do a screencast for us.
Example
