Controlling level of active racks only

I’m using embedded racks in C4 Solo. Thus far I have only needed one active rack at a time, with a CC mapped to master output level.

I am now wondering about using layers, in which case I need control over the levels of each active rack.

Short of assigning a different CC to the level in each rack (e.g. I have 14 racks with various instances of VSTs, so would need 14 controllers), is there a smart way to do this.

If I will only ever need 2 active racks (likely at this stage) I would only want to assign 2 CCs, but these CCs need to know to adjust only the values of whichever 2 racks are active (rather than any of the inactive racks).

e.g. CC 16 and CC 17 can control volume as follows:

CC16 controls active rack 1 = Grand piano / CC17 controls active rack 2 = B3


CC16 controls active rack 1 = Rhodes / CC17 controls active rack 2 = Strings pad

I imagine there might be an obvious solution I’m missing.


A number of ways to do this. Here’s my approach.

For a simple solution, I would have a different CC for each rack volume, but then re-map the incoming CCs to point them at the racks I need to control. You can change this mapping on a State-by-State basis.


Way back I created an MCU-compatible ‘mixer’ rack, and I route my instrument racks there, such that I can have any instrument(s) on any input of my ‘mixer’ and control the mixer faders. I could have my pad instruments on Ch1, and my leads on Ch2, for example. Faders use MCU standards, which are channelised pitchbend messages, but mapping a CC to channel/pitchbend is simple.

If you want to try it, the latest version is at the bottom of this thread: Mixer Rack

Ignore the MDP part - if you want that I’m keeping an updated version in MDPs Q&A pages.

Does Solo have states?

Thanks. No, Solo doesn’t have states, so looks as though I’ll have to get busy with Elf’s mixer (unless there’s a reason this wouldn’t work on Solo?)

My mixer rack has meter on/off States, but I doubt that will prevent you from using it. See what happens.