That is such a tough question. Sound is hard to describe. What sounds throaty to one may sound loud to another. How would you describe a "smooth" sounding exhaust? I would suggest you hook up with guys in Chi-town and listen to their exhausts. Everyone has their tastes so unless you hear it in person you'll be relying on someone's preferences, likes and dislikes. You can measure decibels, but pitch and tone are harder to quantify.

 

yeah i hear you, kind of hard to describe, and a youtube clip is only so accurate. put it this way, here are the exhausts i've had and liked:

BMW E46 - Active Autowerk (AA)
Honda Accord - Greddy/TRust
Acura Integra - Apex

all were quiet, deep, and only opened up at WOT

PS - the hondas were owned over 10 years ago in high school, cant believe its been a decade!