Jakeman,
Prior to last night, I did have the 350's up front spread out near my 80's per your original thoughts. This is when I had a terrible HUMP around 35-40 or so HZ, much worse than the null your seeing.
Which picture are you looking at, because the graph with all subs running from the primary seat looks pretty good me, the problem is you can't satisfy all seats in the room.
I tried moving the 600 around to various positions, with the 350's upfront in phase, but the graphs didn't seem to change much either.
I may try the 350's on the back wall spread out if I can figure out how to route the coax around the walk out door, see other thread.
