Powered sub into Power Conditioner?

A lot of people including myself even keep their power amps off their confitioning units because they sometimes restrict dynamics. I'd think a subwoofer amp would benefit from going directly into the wall as well.

Best thing to do is try it to see if there are any noticeable effects in your system.

Since your sub doesn't usually deal with frequencies much (if) above 40hz ,I'd go for unrestricted current delivery.

My sub is straight into the wall. The MOV's in conditioners or suppressor can clamp current if the sub ask for a lot of it at one time.