Synapse NoDrone Exhaust Resonators are designed to reduce the drone that is common with aftermarket exhaust systems. NoDrone works by bouncing sound waves out of phase with the exhaust system and noise cancelling resonant frequencies to reduce the drone in the system. NoDrone is most effective at cruising speeds and RPMs that correspond within that range. NoDrone allows you to reduce your exhaust drone without having to completely take apart your exhaust system. You simply find a location in the exhaust where you can fit a resonator, cut a hole ~2” diameter and weld the NoDrone resonator in place. It doesn’t have a negative effect on power output, since it does not affect the exhaust flow in the system or present any sort of exhaust restriction.