Sceptres deffinitely have deep deep rumble. They are the best sounding pipes I've heard, but as stated before they are loud. Team Triumph of WI (the guys that make the sceptres) is currently working on some inserts for the sceptres that will keep the deep rumble, but quiet them down a bit if you decide they are too loud. I spoke to the shop early last month and they were working on the inserts and said they would be ready this month.
