Critical subwoofer tip


I assume that everyone already knows the importance of phase matching a sub to the main speakers but it’s a little more complicated than simple 90 degrees or 180. The B&W sub that I have has four choices. In every case there has been a definite correct position that can be non standard. My current setup shined at 270 degrees vs the std positions. It’s completely obvious and the other choices would not have been satisfying. 
From my lengthy experience I would want a subwoofer with several phase choices. I personally don’t see how one could seamlessly integrate the mains and the sub without this flexibility. No one asked but i thought this info might be useful to anyone purchasing a subwoofer. YMMV
4425

Showing 3 responses by mitch2

Is there another way to figure out the optimum phase except to listen?  Maybe use an SPL meter at the overlap frequency, play the same program material at the same volume setting, and then set the phase at whichever setting achieves the highest SPLs?
Setting the correct phase is much more important with a single sub, and less important to not important at all as you add additional subs.
Does it also become less important the lower you set your sub's roll-off point?  For example, I have two subs set to roll off at a pretty low 40Hz because of the low frequency extension of my main speakers.
Thanks @golfnutz I get it and their reason to listen for minimum bass makes sense.  I suppose with two subs, the method would be to measure and adjust each sub separately, one at a time.