Ok, I made a statement few years ago and they all thought I was crazy. Now that at least one person shares my experiece with sub-phase problem I will repeat what I said then:
My main speakers are full range, VA Mahlers which are porter, and my subs are two rels, a stentor III and a stadium III. For months i tried to figur it out but i dont think i have any doubts now. By setting the speakers as large and augument them with the subs at 22hz and below, When I did that with the subs' phase set to 0 cancelled the speakers below 25hz while increasethe output above that frequency. For istance, when the phase is set to 180, there is a normal boost below 25hz and a decrease of output above that. I alway thought it was a phase interaction between the mains and the subs. Note that if you ask Sumiko which sub to add to the VA they will strongly suggest the stentor. Go figure...
My main speakers are full range, VA Mahlers which are porter, and my subs are two rels, a stentor III and a stadium III. For months i tried to figur it out but i dont think i have any doubts now. By setting the speakers as large and augument them with the subs at 22hz and below, When I did that with the subs' phase set to 0 cancelled the speakers below 25hz while increasethe output above that frequency. For istance, when the phase is set to 180, there is a normal boost below 25hz and a decrease of output above that. I alway thought it was a phase interaction between the mains and the subs. Note that if you ask Sumiko which sub to add to the VA they will strongly suggest the stentor. Go figure...