unsure of loud exhaust

I recently bought a 95' 325i, only 80,000 miles. I noticed when I first test drove this car that the exhaust sound was a little different than most cars. I thought maybe this was normal for a BMW (I've never owned one before). Several weeks have gone by and other people notice the sound. I finally found someone that was familiar with BMW's and they said it wasn't normal. I looked under the car following all the exhaust pipes, and I don't see where anything has been altered. and I don't see any rust or pin holes in the exhaust. everything looks like factory. So does anyone have any knowledge on this? should a BMW exhaust sound louder than most cars? could this be a serious problem that I should have checked out by a specialist?

thanks for any help.