I have a Onkyo 3009 featuring XT32 hooked up to PSB Image T45 mains, C40 center and B15 surrounds. After running Audyssey the AVR has set my crossovers to 40hz for the mains, 60hz for the center and 50hz for the surrounds, with the LFE set at 120hz. All crossover settings are within the speakers +-3db rating specs. My question is should I manually adjust my crossovers up to 80hz? If that is the case what is the point of having tower speakers or speakers in general that go below 80hz?