I'm not familiar with B&K's set up. The processors I've used, keeping to basic set up, nothing customized, the high & low pass generally only kick in if your rears, mains or center is set to "small", the filters control what frequencies go to the sub and what goes to the speakers. From what I understand you keep your sub crossover set either to "bypass" to take it out of the circuit or turn it all the way up, the LFE is controlled automatically by what's encoded on the movie soundtrack. So if your Infinity center was rated to play down to 90Hz, and, if set to "small" as it should if it was really rated at 90Hz, you'd begin with your preamp crossover about 90Hz to see how it sounds and maybe go up or down depending on how it sounds to you. What I said is strictly for movies, I don't use my HT processor for music. Sometimes I do use the HD radio for background and found I had to choose a setting "both" in order for the sub to work for stereo.