Audio Monitoring - 5.1 Mix Room

The iMac has built-in speakers, a built-in microphone and a MOTU16A audio interface.

Most applications are configured to use the MOTU 16A audio interface.

Grace m906 Monitor Controller

The m906 Grace monitor controller is used to select audio sources and to adjust the volume.

• The big silver knob on the lower right is used to set the volume.
  • Double click the main level knob
    • This will set the volume to 65dB
    • adjust as needed
• Source Select button:
  • A = MOTU 828 audio interface
  • B = Mixer
• Mono: press down to monitor in mono.
• Mute: turns the volume all the way off.
• Dim: pressing the button lowers the volume by 20dB
• Monitor Select: Leave set to A. The up position.

Speaker Levels

There is a Mackie Big Knob volume control box to the left of the iMac

1. Start with the output level down
   • The silver knob is turned all the way to the left
2. Set the Source Select button to A to select the MOTU 828 output.
3. Start playing sound in an application.
4. Slowly turn the silver knob to the right to increase the volume.

Headphone Levels

Headphones can be connected to the front of the MOTU 828

There is a small headphone volume knob above the headphone jack on the MOTU 828

1. Turn the silver output level down on the Mackie Big Knob volume control box  
   • The knob is turned all the way to the left
2. Turn the headphone volume down
   • The is knob turned all the way to the left
3. Connect headphones to the headphone jack on the MOTU 828
4. Slowly turn the headphone volume knob to the right to increase the volume