No Duc here but you can listen to different exhaust sounds in these two videos:
Hope this helps
For me, I'm always a fan of Akrapovic as I had one on my old bike
. Their exhaust releases a more refine deep melody. Plus the quality and the look it self is clean and professional. I get a lot of compliments on the look and sound of the thing.
Unfortunately, they haven't develop one for the 696 as I'm waiting for one to come out (cross my fingers)
For comparison between Termignoni and Akrapovic on an 848: