i have ref 9se amps, by getting info here on the gon i cut the cap between the speaker terminals, while i had the cover off i added a piece of rf emf mat on the inside of the cover, it was kind of a pain as the ref 9s has a brace that runs front to back, the width of the mat is to thick, in the end i got it on, both of these made positive improvements to my ref 9ses, IMHO good luck