I deleted the rear cats and "H" pipe and inserted a "X" pipe. No drone. I have the resonator intact and deleted the lead-weight muffler also. Sounds very civilized until WOT then sounds like an uncorked Ferrari! But no drone at all in the cabin. All sound is distinct out the rear. Got mine here: 2.25 in. SS version

http://mandrelbendingsolutions.com/x-pipes/