I'm considering buying a Mystere CA21 preamp that invert's the output signal. The common practice is to change the polarity at the speaker terminals. I'm not too wild about that idea, however because my speakers are self tri-amplified (ATC SCM50 ASL Pro, with built in active crossovers and amps). Seeing as how the preamp has an unbalanced RCA output and the speakers (amp) have a balanced XLR input, would reversing the two signal wires work? (On the XLR end I would swap the hot and neutral, pins 2 and 3,and connect the screen to pin one and the case. The screen would float with no connection at the RCA end. The amp/speaker has a three wire AC plug. Assuming the ATC's are truly balanced, I can't see where this would cause any harm. Both manufacturers haven't, so far, been of any help.
Any thoughts on this are appreciated.