Gieseman, your settings seem off to me.

The sub should be on by-pass/highest cross over setting on its amp, otherwise you are missing the low frequencies from the center and surrounds which you have crossed over well above 80.

Or are you refering to the LFE channel in the receiver for the sub and it is set at 80, which many suggest should be set to 120 or the highest possible in the receiver.

Jason
M80 v2
VP160 v3
QS8 v2
PB13 Ultra
Denon 3808
Samsung 85" Q70