I may have misinterpreted what the OP wrote:
"Good deal. So set xover in my Denon to 80hz for center just like the L/R 170s. Leave the LV12R xover on 120hz and run Audessey? "
I took it as saying that he had set the xover of the pre/pro or AVR at 80Hz for LCR and 120Hz for the woofer. Re-reading it I guess he meant the xover knob on the sub!
Is there an emoticon for an embarrassed red face????