Originally Posted by Pianist718
I thought that when a receiver has 7.2 (2 sub capability), when you do the room correction run with Audessey or the like, it actually sets separate specs for each sub and thus the sound is WAY better. Am I off here?
yes, you are off... not your fault though, it's easy to be confused by marketing specs.
the truth is that the VAST majority of receivers that call themselves "7.2" are really just 7.1 units with an internal y-splitter feeding two identical sub outputs. The "point 2" part just designates that there are two outputs, but they receive the same signal.
among Audyssey equipped units ONLY those with MultEQ XT32 will have a "true" dual sub calibration, this is branded as "SubEQ HT" in the marketing specs. Note however that even these waters have been muddied by the introduction of the Onk 818, which has XT32 but does NOT have SubEQ HT.
all that being said, if you have the wherewithal to optimize your dual subs prior to running Audyssey, you can still achieve excellent results without this "dual sub calibration" software. The SubEQ HT just makes the job easier by level matching and time aligning them for you.