I had a similar question to yours in that I wanted to find a balance between the various "loud" and "soft" patches of the VCS and the Roland sound modules I use, so I began an experiment which I still haven't quite finished yet because of the complexity involved. I experimented by turning single VSC instruments playing the same midi sequence into a wave file which I then imported into an audio editor and noted the RMS output of the wave file. In turn I varied the different possible parameters and recorded the RMS in each experiment. The experiment is far from complete in that I've only compared the acoustic Piano, the guitars, and the acoustic bass guitar. I haven't messed with the project in a while, but these look like the average of the calculations I had when I stopped. Perhaps they can be useful to you, but keep in mind, if they work for your synth, they are only averages that may get you close.

VSC Dry Calculation:
CalcRMS = .000 000 06x² + .003x - 55.1
x = (VelVal*CC7*CC11)/127

VSC Wet Calculation:
CalcRMS = .000 000 06x² + .003x - 55.1 + (.7/127) * RvbVal + (5.2/127) * ChorusVal

J Blatz

JBlatz