I attended an F1 race in the V10 era. And my god, the noise! It's like the sky was being torn to shreds. The sensory experience is/was definitely a huge part of being a live spectator. I've been to a few other kinds of races, and nothing ever really came close to that. Just the raw power/pure violence of those cars coming out of a turn with that ear splitting shriek is just phenomenal.
That being said, the booz fueled americana tailgate party weekend that is the indy 500 is pretty high up there in great times. But the actual racing was waaaaaay super less entertaining.
I once walked the footbridge over the hillclimb at Goodwood during the Festival of Speed as a V10 F1 car went underneath. Was something else entirely.
Seeing the musical demos the Renault team used to do was always interesting too - if you haven't heard an F1 car play God Save The Queen [0] it's a great watch (and a reminder about how controllable they are).
That being said, the booz fueled americana tailgate party weekend that is the indy 500 is pretty high up there in great times. But the actual racing was waaaaaay super less entertaining.