Yes, same topic. Does anyone produce a definite guide to doing this. Having downloaded snap bug and worksheets and aquired an SPL meter. Basically the response curve is all over the place, theres as many sharp troughs as there are peaks. Certainly there is a very strong peak around 30-40Hz, but its way over 12 Hz attenuation using PEQ on the SVS. Then I noticed a comment, mentioning that you should be using pure stereo and not 5.1 doh.......then you should use warble tones...double doh TBH Ive got the freqency set to around 35Hz, Q at around half way and level at the top of its range. Ive moved the sub around, set it on blocks etc. Then I just sat down and watched the Matrix. Is the sub calibrated correctly ? who knows the Helicopter crash scene sounded amazing, something was vibrating (might have been the sub itself, difficult to tell at those volumes). I noticed that one of the bell mouths on one of the port tubes was vibrating against the heat sink on the bash amp, turned it through 90 degrees, which seemed to solve the problem, but maybe it starts to move at higher volumes. I tried the test tones on my hifi through the full range speakers and was amazed to find that they managed 20Hz without a problem and had a flatter frequency range from 25Hz to around 55Hz well into 90dB. But that might be because its pure stereo. Is it really necessary to do all this equalisation stuff ? I really dont see how you can rid the room of resonance, standing waves and peak frequencies, but maybe Im wrong? Any thoughts, a nice open discussion would be good.