On my receiver, I set my subwoofer crossover at 120 Hz due to my very small main speakers. My current subwoofer has no internal crossover, so the setting is easy. In the next month or two, I'm going to be upgrading to a passive subwoofer for which I'll need an external subwoofer amp. I've narrowed it down to 2 amps, and they both have built-in crossover settings. One of the amplifiers allows you to disable the built-in crossover as to not interfere with the receiver's crossover. The other one ($50 cheaper) has a crossover setting, but you can't disable the crossover. You can just turn it up to 160 Hz. I was looking at the frequency response graphs of crossovers, and the receiver's 120Hz crossover would overlap the sub amp's 160 Hz crossover in a major way. My thinking is that the 160 Hz sub crossover will reduce output in the higher frequencies (100-120 Hz) that I DO want to hear. Is this the case? Should I pay the $50 extra for the ability to disable the extra crossover setting? There are many posts on the topic, and most people just turn their sub XO to max (150 or 160). For a typical 80 Hz receiver crossover, the resulting overlap is much less than it will be in my case, though. Thanks for the help!