Chris Kyriakakis March 24, 2012 09:45
Hi Jens,
First let's be sure we are talking about the same thing. There is an LPF filter in the Denon that is applied to the LFE track only. This must always be set to 120 Hz because the LFE track is authored with content up to 120 Hz. But, this filter has nothing to do with crossovers.
There is also a filter on the back of the sub that is applied to the incoming signal. That filter may interfere with the lowpass filter applied in the Denon to the bass managed bass signal and so we recommend setting it as high as possible.
But, again, the LPF for LFE filter is not at all related to the crossover filters set for the speakers. It only applies to the LFE track found in 5.1 content. You can easily test this by playing 2-ch stereo that has no LFE track. Changing the LFE filter will have no effect on the sound.