I've not tired this (I have lots of external compressors/FX/mixers, Sonar X3 and most of the other usual SW suspects. In other words, I have multiple ways to skin that cat in real time or post production) and would have to ponder a while on the best "how to" with this Rube Goldberg approach BUT

Audacity is free

http://audacity.sourceforge.net/

it has a built in "Audio Duck" app already (I've used it for "over dubbing/inserting" of narrative audio onto already recorded live operational test audio; nothing to do with music). Besides what Audacity makes available for free there numerous other free compressor plug-ins out there (with SSB/ducking, etc.).

Just bring all audio in into Audacity and select tracks to duck and the control track (I assume a vocal track but could be anything) do the "ducking and then bring whole thing back into RB if needed - may not even be necessary. Is this a "final" track mix? Technically you could "master" in Audacity - it can use all your PC's existing VST plugins?

In any case, I hope you can get some variation of RB, your other existing commercial apps, and the plethora of free apps out there to do what you want without shelling out 'mo mony.

Good Luck
Larry

Last edited by Larry Kehl; 10/27/14 03:53 PM.
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