I've had the aural pleasure of hearing an Audi R8 V10 at full noise zoom past me on the M1 motorway, as well as part of the local Audi roadshow. It has to be heard.
As for a V8 note, I'm partial to the Mercedes benz, C63 AMG. Deep and crackly, it's 6.3l of DOHC V8 goodness.

