Если бывал на ультимэйтметалл, то может видел что вроде не очень они там котируется. В смысле пивеевские кабы...
Вот кусочек некоего интервью со Снипом:
" I am not keen on Peavy 5150 cabs for recording purposes, and tend to use Marshall or boogie cabs with the 5150 head. For the sounds you are after, mic with a shure SM57 on axis very close to the cone (maybe an inch from the cloth, slightly off centre to the middle of the cone. Experiment to find the sweet spot. I often also use a sennheisser MD421 off axis about the same distance away - but beware of phasing if you use more than 1 mic."
Source:
http://www.davechang.co.uk/ "Those speakers [in a 5150 cab] are actually a rip off (according to Peavey) of the Celestion Green back, so the centre of the cone is pretty small, which is good. Get a mag light, and point the 57 directly at the centre of the cone, straight on, about an inch back from the grill cloth. I usually move it about half to 3/4" off centre so the edge of the 57 is aiming at the edge of the centre of the cone. Again, trust your ears a bit, if you think the mid range is more to your liking a bit (and I mean a fraction) more off centre then go with it. Listen to the fizz in the highs, and also the cloudiness in the lows, but to me the mids are where a good tone is."
1 cm makes a big difference on 25 or 30 wt cones because the centre is so small. You can find a nasty phasey sound pretty close to the centre so ,...after all why eq it if you dont need to, all you are doing is messing with the phase.
You really shouldn't overlook it, 1cm back and forth from the grill gloth makes a difference as well, especially with the tightness of the low end
Left and right can sound different, depending on how cab is wired.
I always check every speaker as they all sound different, and if one is on its way out, it will alter the impedence.
one thing I have found though is the 75wt celestions work better at concert pitch and the 30's better with the lower tuning.