Nitrous: i usually only get to hear the car from the inside, because i'm the one driving it. When i picked it up at the mechanic's last week, he backed it out, and at idle/low speed, it's a little raspy but not too loud. (I'm running the stock exhaust). The car makes alot of torque way down low in the rev range, and it's awd to boot, so it's pretty mild mannered unless you get on it. At about 4k rpms, it starts to go from a hummm, buzzz sound to a deeper growl inside the cockpit, keep in mind that you are doing over 120 in 3 gear and still have not redlined- at 140 in 4th, you still have easily 70% pedal left. You also begin to feel a stronger buzz in your ass, because you are basically sitting right on top of, in front of a 6 litre 12 cyl. engine that conservatively makes 550hp in stock form. The car is extremely fast, not quick if you get the distinction, and at go to jail speeds the car will not be working very hard if you are in the correct gear. I have not done any top speed runs with it yet, i will when i take it out west. I don't know what the sound bites make it sound like, usually, the ones i hear on the Internet can't capture what any car or bike really sounds like in person. The absolute nastiest exhaust i've heard in person is on a 512 BB/LM, a late 70's flat 12 Ferrari racing car: when the car is revving in the pits, it shrieks, at aircraft take-off decibels, and will make you flinch, even standing some distance away from the car.
The last car I had before the Diablo was a GT2 set up as a club sport with a Fabspeed exhaust- it was superloud. People loved it, but after a while, it droned, and gave me a slight headache.
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