I replaced my mufflers on a 2008 Audi A8L with these. WOW! Deep, low growl between 1.5-2,000 rpm. Silence after 2k. The acceleration sound is perfect, you can't ask for more. There is no high pitch at all. Just drove from Los Angeles to Eureka and back. Took 1 up and 101/5 south. a deep rumble all the way up, but not too overwhelming. Quiet downhill. PERFECT!