An Aggregate Device is a virtual audio interface within your computer system which utilizes the inputs and outputs of one or more physical audio interfaces connected to your computer. This setup allows you to use more than one audio interface with your audio application.
For instance, you could use a guitar interface with a single input and the headphone output of your computer at the same time to monitor the audio, or use the internal audio input of your computer to record a mix in TRAKTOR when all inputs of your TRAKTOR audio interface are being used for Timecode control. Follow the steps below to learn how to set up an Aggregate Device:
- Launch the Audio MIDI Setup, which is located here: Macintosh HD > Applications > Utilities.
- Click on Window in the menu bar and choose Show Audio Devices.
- In the Audio Devices window of the Audio MIDI Setup, click the Add (+) button. A drop-down window will appear. Select Create Aggregate Device from the menu.
- A new aggregate device will appear in the list on the left side of the window. To rename the device, double-click it.
- A list of all the physical audio interfaces currently connected to your computer will appear in the selection section on the right-hand side. Check the boxes to enable the physical interfaces you require for your aggregate device.
Note: In addition to displaying the currently connected audio devices, the number of inputs ("In") and outputs ("Out") available for each device is also listed.
- Close the Audio MIDI Setup.
- Open an audio application of your choice and select the newly created Aggregate Device as your input and output device. Note that the inputs and outputs have generic names. They follow the order of the devices in the Aggregate Device selection window as shown above.
You can now use the inputs and outputs from multiple audio interfaces within your audio application.