My statement comes from what Ian, Alan, and Chris (Audyssey), and I believe Dr Toole, say you should do in most situations. I've played around with phase until I'm blue in the face, graphs up the ying yang, etc. Phase, is only one component of how a speakers works within a room. Placement, room size/dimensions, etc. also affect FR. In all the testing I've done with 3 subs and many many placements, I always get better results using 0 phase.

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