hello, this may sound unorthodox, but we usually play those model t's on
15" speakers, like old kustom 2x15 or 3x15 cabs (aren't these altec lansing?), jbl d130f (like in the old fender dual showman 2x15 cab $$$$) sounds extra loud as these speakers are extremely efficient (more db, less heat conversion) and have great tone too! also very efficient and great tone, but cheaper: celestion kt-200 speaker. with those 15" speakers the amp has a deeper bottom end, but especially a deeper 'growl' so to speak (more low-mid, around 250 hz), without losing the high definition and mid bite (somewhere between 500 and 1000 hz), those jbl's were originally used by surf guitarists (dick dale modeled it!) who wanted sharp high for their staccatos and deep low for their twanging reverberation. sunn sounds great too on those big speakers, randy holden from population II was using
those 2x15 cabs as well and you can hear it on the cd. cheers!