With my NAD pre/pro, I have my mains set to 50Hz, center to 60Hz, and surrounds set to 80Hz. I would think NAD's AVRs of the same generation would have the same capabilities. The NADs have a great feature right on the remote to boost/lower surrounds, center, and subwoofer. Also tone controls can be engaged(bass & treble boost/lower) for the mains and center channel dialog boost/lower. You can even disengage Audyssey and apply tone controls where needed or not use them at all.
Bill
Bill