Audio Midi Setup: Audio Devices window

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Audio Devices window

Use the Audio Devices window of Audio MIDI Setup to set up audio input and output devices you use with your computer, such as microphones and multichannel audio interfaces.

Option Description

Audio device list

Any audio devices that are built in or connected to your computer or display appear in the audio device list on the left side of the Audio Devices window.

To use a device for sound input or sound output, or to play system sounds, select it, and then choose an option from the Action pop-up menu (looks like a gear).

Add button (+)

To create an aggregate device or a multi-output device, click the button.

If you have several audio devices, you can use them as a single device known as an “aggregate device.” By combining or “aggregating” devices, you can increase audio capacity without purchasing more expensive multichanneled audio equipment.

If you have several stereo output devices, you can have audio play through all of them by creating a multi-output device.

Audio device options

On the right side of the Audio Devices window, choose the options available for the device you’re setting up.

Clock source

Leave the “Clock source” pop-up menu set to Default unless you’re using an audio device that sends its own timing (clock) messages.


Your Mac automatically chooses the appropriate option from the Source pop-up menu.


You can choose the sample rate and bit depth from the Format pop-up menus. Make sure they match the appropriate settings for your audio device.

Hardware Rate Converter

If your computer contains support for the hardware sample rate converter, the Hardware Rate Converter pop-up menu is available in the Input menu. When you choose Automatic from the pop-up menu, the hardware sample rate converter is turned on if the audio samples coming in are PCM and formatted according to the international standard IEC 60958-3. The hardware sample rate converter is turned off if the input stream is encoded. You can also choose Enable or Disable from the menu to keep the hardware sample rate converter turned on or off.

Volume sliders

If software volume control is available for your device, the Volume sliders are blue to indicate they are active. Drag the sliders to set the volume for each channel.

Configure Speakers

To set up surround (multichannel) speaker configurations, click Configure Speakers, and then choose the type of configuration you want to use.

If an audio device doesn’t appear in the list in the Audio Devices window or doesn’t work, make sure it’s connected correctly to your computer and that you installed any software included with the device.

Published Date: Sep 3, 2015
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