Hardware mixing desks sometimes contain separate channels designed specifically to enable the engineer to submix—in other words, to route and control the signal flow of multiple channels at once using a single channel strip. Analog mixing desks often utilize Voltage Controlled Amplifiers (VCAs) in their circuitry for these submix channels, hence the name “VCA groups” for this kind of channel strip. You can use VCA channel strips to control the volume, or automate a submix, of tracks that are assigned to the VCA group.
While much of the functionality of VCA groups can also be accomplished with aux (auxillary) channel strips, VCA groups have some unique advantages:
VCA groups can contain channel strips that are routed to different outputs.
VCA channel strips use less processing power than an aux channel strip utilized as a group master.
Adjusting the volume of a VCA channel strip changes the volume of each individual channel. This can be important when mixing. For example, if you use post-fader send effects, the amount of signal sent to an effect by a channel assigned to a VCA group follows the VCA group volume changes.
Do one of the following:
Choose Options > Create New VCA Fader from the Mixer menu bar.
Select one or more channel strips, then choose Options > Create New VCA for Selected Channel Strips from the Mixer menu bar.
You can delete channel strips as described in the Channel strip types overview.
Click the channel strip’s VCA slot, then choose a VCA fader from the pop-up menu.
Click the channel strip’s VCA slot, then choose No VCA from the pop-up menu.