Exhaust Mod Help

Hi, so I have a Mercedes c300, I took out the stock exhaust and put in straight pipes with a small pipe in between connecting them and it doesn't sound as good as I would like it to. The engines a V6 what would you guys recommend I change to get a deep low growl kinda sound and if possible only loud during high revs and quieter when just at 1000-3000rpm. A friend suggested put back the stock exhaust and do a secondary cat delete. Opinions?

See if the boys at Borla have anything for you. They usually try to engineer in the "right" sound.