I have a Yamaha dsp z9 with kef Q5 Front speakers And Yamaha Yst sw-300 subwoofer,my rear effect speakers are kef q3 floorstanders, i was wondering what your recomendations would be for the crossover settings on the subwoofer and amplifier should be ,according to Kef the speakers are 39KHZ ,the amp settings are from 40 khz up to 200 khz and the crossover dial on the subwoofer is 40khz - 140khz , i want my main speakers to do as much work as possible - i.e low frequency before the subwoofer cuts in so i think i should be setting both crossover settings to 40khz, would you say i was correct regarding this Andrew?