[quote name='jensenmann' post='522065' date='Jun 23 2009, 09:19 PM']As long as you´re in a room with your cabs the room will add loads of modes and combfilter low frequencies anyway, no matter if you have one cab, two or twentyseven. As it´s mainly a function of the placement which is depending where you are standing on stage there´s not much choice and you will have the trouble in a kind of unpredictable way. No way to avoid that.
Oper air is different. One cab is perfect (besides first reflection from floor and - probably neglectable - from roof. Two cabs will give frequency depending combfiltering and frequency depending dispersion.
All the theory besides 2x 8x10"SVT rock. Your guitarplayer shall live in fear :brow:[/quote]
From my understanding, even one cab ins't perfect, since the speakers are next to eachother, just close enough that the null will not be the same for each of your ears. Two cabs directly side by side might also produce an acceptible pattern, so you can get away with it. But one each side of the drummer and from experience, the filtering is silly.
Of course, you can get bone cruching sound out of multiple 8x10s: