What is 'VBus' and how do you use it?

Apogee’s VBus creates virtual hardware buses to allow expanded routing of audio within one application or between different audio applications. For example, it’s possible in Logic Pro to record a submix of multiple audio tracks onto a new audio track as described below. It’s also possible to route between two audio applications by selecting a VBus output in the source application and a VBus input in the destination application.

VBus is only available in the Symphony system. You must have either a Symphony 64 PCIe or Thunderbridge and at least one Symphony I/O, AD16x, DA16x, Rosetta 800, or Rosetta 200 to use it.

To use VBus: If you have a Symphony system and everything is connected and configured properly, launch 'Apogee Maestro 2' from your Applications folder and go to the 'System Setup' tab.  Go to the right side of the window and click the drop-down menu under 'VBus' to select how many channels of VBus i/o you would like to use.  As soon as you engage VBus, quit all open applications and restart your Mac.

In order for VBus I/O to appear in your audio application’s I/O list as VBus In 1-2, 3-4, etc, it’s necessary to specify the use of the Symphony driver’s names in the application’s I/O list. For example in Logic Pro X, open MixI/O Labels and option-click on all the I/O found under the Driver’s I/O Label column.

As an example of how to use VBus, let’s record a submix of drums onto a new stereo audio track in Logic.  In Logic’s Track Mixer, set the outputs of the individual drum audio tracks to VBout 1/2.  Create two audio tracks (or one stereo track) and set their inputs to VBin 1 and VBin 2. Record-enable the new track and commence recording. The new track will record the mix of the individual drum tracks.