It’s known that those 2.5-liter N/A V6 engines used in DTM/ITC championship by Alfa Romeo, Mercedes and Opel had an epic sound, especially the intake noise was something unmistakable.
But I’ve always found them quite muffled on the exhaust side (maybe due to regulations, don’t know). During the 2018 AvD Oldtimer GP at Nürburgring they recorded this 1996 Alfa Romeo 155 V6 Ti with a fully straight piped exhaust racing around the GP-Strecke. Listen to that V6 singing at 12,000 rpm!!