I had a '01 5.9 Dodge/Cummins. Damz thing was loud enough to kill normal brain cells.
Girl in the hut in front of Zion National Park refused to open her window till I killed the racket. I never liked the racket from the 5.9. However it was handy when some rude dude turned on his boom box/stereo while sitting in a parking lot/drive in/etc. Just fire the 5.9 up and usually the dude got the message.
I jumped on the 1st new gen much quieter '03 HPCR 5.9 my Dodge dealer got in. Much better.
Having over 1.2 million miles total (850k in a 11 years period) behind the wheel of 460/450 one ton DRW trucks pulling for a living has left me deaf in my left ear and require a hearing aid in the right ear. Back then I was young and dumb and thought my trucks had to beller and roar with burned out glass packs or straight pipes.
No more engine racket or exhaust drone in the cab for me. I love to drive the wifes new '16 1500 chevy....such a quiet ride.