Step 1: Open up your Application Folder and then open up the Utilities Folder
Step 2: Once in the Utilities folder, run the "Audio MIDI Setup" Utility (icon looks like a single octave keyboard).
Step 3: Output Routing
PLEASE NOTE: If you want to listen to Headphones or the Main Out on your AudioBox VSL interface you'll need to set your outputs as follows:
Main Output Routing
Headphone Output Routing
|AudioBox 1818 VSL||Outputs 1 and 2||Outputs 7 and 8|
|AudioBox 44 VSL||Outputs 1 and 2||Outputs 1 and 2|
|AudioBox 22 VSL||Outputs 1 and 2||Outputs 1 and 2|
The AudioBox 44VSL and 22VSL, your default settings for Output will be Output 1 on Left and Output 2 on Right, so there is no need for any changes.
The AudioBox 1818VSL headphone outputs are hard wired to Ch 7 and 8 outputs.
This way you can use the Main Mix and Headphone Knobs on the front of the 1818VSL to control Main Output and Headphone volume levels independently.
To change the Outputs on the AudioBox 1818VSL to 7 and 8, click "Output", then click on "Configure Speakers". See below:
Step 4: Per the chart below select A 7 as the Left Front Output.
Step 5: Per the chart below select A 8 as the Right Front Output.
Step 6: Your final Audio Device Output will look like this.
Click "Apply", then Click "Done"
Then close Audio MIDI Setup.
For standard computer use such as iTunes, YouTube, Movie Watching, etc, may choose need to toggle your output based on your needs.
Now you can adjust your headphone mix using the headphone volume knob on the front of your AudioBox.
However if you want to then route the main output of the computer back to the main speakers, you'll need to come back to this menu and set outputs to be 1 for Left Front and 2 for Right Front.
Another option would be to connect your studio monitors to outputs 7 and 8 on the back of the 1818 VSL. This will render the "Main" knob ineffective for adjusting your monitors volume, but the volume fader in OSX will work correctly. This will allow simultaneous output from the headphone jack and your studio monitors.
If you're using a DAW such as Studio One, you can use the Mixer to route your headphone mix using a Cue Mix which can be assigned to Outputs 7 and 8, this you can setup in your Mix Routing in your song.
To Learn more about how to do this, click here.
Please contact PreSonus Technical Support by creating a Support Ticket at My.PreSonus.com for further assistance.