Part of the problem is that the advice given to consumers for sub setup is just plain wrong!
Everyone is told to balance all channels to 75dB using white noise and a SPL meter - this is a flawed method.

The professionals use the following method:
1. Balance the main channels at 75dB with white noise.
2. Create a test tone CD (this is easy to do now with modern PCs and the internet) with alternating tones straddling the crossover point. So for a THX 80Hz Xover, you need 60Hz,70Hz,90Hz,100Hz.
3. Using the sub volume only, try to balance the volume of these tones so that the alternate pairs, 60+100, 70+90 are at roughly the same SPL.

With all speakers set to small it is generally unnecessary to play with the phase control, even more so since the distance measurement to the seating position in the processor also acts as a phase control.

Mark
G68, baby Genelecs, Humax Foxsat, Oppo+Vanity93, Toshiba HD-A35, Pioneer CLD-925 + Meridian 519, various other random bits and bobs
Got a black G08.2 you want to sell?