>>I had heard null-ness (I'm prone to making up words as I go, so bear with me gang) can be made less null by playing around with the polarity switch on one of the two subs.
Yes and no. The phase switch helps in two specific cases :
1. You have two subs and the signals from them are cancelling out in a part of the room where you like to sit. Flipping the phase means the signals will add at that point rather than cancel, although remember that this is very frequency specific.
2. You are running your mains in "large" so they are producing bass alongside your subwoofer, with the same cancellation issues as in (1). Here you are flipping phase relative to the mains, but the effect (and frequency dependence) is the same.
With a single sub running your mains in "small" the phase switch can affect how smooth your response is in the crossover region between mains and sub but that's it.
M60ti, VP180, QS8, M2ti, EP500, PC-Plus 20-39
M5HP, M40ti, Sierra-1
LFR1100 active, ADA1500-4 and -8
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