I have connected my sub using RCA inputs to the sub out of my Harman Kardon 320 with a low pass filter of 60hz in the setup menu of the receiver. Now, for movies, my questions are: - should I turn the LFE switch on the sub to ON or OFF? - and how would turning the LFE Switch to On or Off affect how to adjust the crossover switch on the Sub (can be from 50-200hz)? For music: - would the above settings be different if I were to use the sub for music I guess I just don't understand what the LFE switch is for. I also read somewhere that if my sub didn't have the LFE switch then at some frequency point the output of my sub out would interfere with the sub's crossover setting. I hope I have the terminology correct.