This is typical of most avrs, that the ".2" sub pre-out is merely an internal splitter. Some avrs have the ability to separately handle two subs in terms of level/delay, usually these are at the high end of the avr model range. Denon avrs with AudysseyXT32/SubEQ can do this. I thought I'd read some versions of MCACC can do this, but it should be evident in your manual, not familiar with newer Pioneers (since my last Pioneer died an early death plus Onkyo buying them they're kind of off my list).