Why use an Aggregate Device?
Certain DAW's allow the use of only 1 audio interface or driver. When using AIRA products via USB in conjunction with another audio interface, it's advisable to create an "Aggregate Device." By creating an aggregate device, you can utilize any combination of audio interfaces and their I/O's.
Keep in mind, in order for aggregate devices to work correctly, the interfaces used must have matching sample rates.
Let's Aggregate!
In Audio MIDI Setup, the list of available audio devices will be visible on the left side of the window. Notice how there is a TR-8 and a STUDIO-CAPTURE audio interface available for use. Click + on the bottom left, and click Create Aggregate Device.
In this case, our speakers are hooked up to the STUDIO-CAPTURE, but we want the USB audio from the TR-8. Click the the output interface first (STUDIO-CAPTURE), then the additional input interface second (TR-8).
Double check the sample rates. The TR-8 uses 96kHz, so change the STUDIO-CAPTURE's sample rate accordingly. For our session, we will want the TR-8 clocking the DAW, so change the Clock Source to TR-8.
Enable the Aggregated.
For this demonstration we will be using Reason 7. Open DAW. Open Preferences. Select "Aggregate Device" under your DAW's Audio Device setting.
Now we are ready to go! Keep in mind the track inputs are dependent on the amount of I/O's of each interface. In this case, a TB-3 is plugged into channels 1-2 of the STUDIO-CAPTURE, but the TR-8's inputs start on 19-20.