I would love to hear the differences also.. Good question. My Vortech V2 SQ is not exactly quiet.. I couldint imagine anything louder. It would be just completly anoying after a while.
i dunno where u can listen but I know someone with a vortech and a paxton novi 2000 and a series 2. The paxton is the loudest, followed by the vortech, than the series 2. I don't like the sound of superchargers....i dunno why.
Look for a shop with a dyno in your area. You can usually find Mustangs with superchargers there. Local dragstrips are another great bet. Also look for car shows (particularly ones that feature Mustangs)...
BTW...the Novi 2000 has a slight whistle at idle/light loads, but is drowned out by the exhaust at WOT.
I've got a Vortech SQ, You can hear it fairly well at idle and up to about 1.8k RPM. Then it's drowned out by exhaust.
It's funny, when I leave my car running at a gas station to go in for a drink, ppl look at me like "What's wrong with your car?" I'm just waiting for somebody to tell me I have a belt loose...