LOL, My stock exhaust was really quiet on my GTU.
My SE had a holy right muffler and was still pretty quiet.

My GTU now has the Corksport Single. Hehehehe
Let's just say I put it in neutral going past parked cars and still set off alarms.

I am waiting for CS to come out with a silencer.
My room is in the back of a Stucco exterior house and I can hear it idling in front of my house.

 

i have original exhaust on my 89 vert still...its quiet except at idle with the ac on..the cats make o shitload of rattling!!..will be kicking in some straight pies to replace the cats soon...fla no inspection for smog!!

 

Stock system on my '90 GX. Quiet to 5500, then it growls like an elephant... or something.

Edit: Wow, my 100th post. W00t!