I'm looking into decoding some old SQ Quad Matrix recordings that were broadcast in the 1970's. Decoding involves changing the phase of the channels by 90 degrees, among other things. Is this something that Vegas can do? What about Sound Forge?
Try the freeware 'PhaseBug' VST plug-in from [url=http://www.betabugsaudio.com/plugs.php] - it provides independant L/R variable 0 to -/+180 degree phase shift controls, works nicely in Vegas.