A lot of what we remember is also dependent on the acoustics of the theater we saw it in, and what the gear was set at too. Not every theater cranked it up to eleven like they do these days. But, this was also the era of Sensurround, which was legendary for causing plaster to fall from the cieling!

I saw Logan's Run in 1976 at a theatre that was probably converted into a twinplex. It was nearly drowned out by Midway's Sensurround soundtrack playing next door. Also the last time I ever got into a theater while the previous showing was just ending. Something Star Wars put an end to, as theaters didn't want people sitting in there watching the movie five times and only paying once!

My main memory of seeing Empire in 70mm was being amazed that noises on Dagobah were coming from behind me! But I recall feeling things like the first snowspeeder flyover as much as hearing them.

Front row in the balcony seemed to be the sweet spot too. Something I remembered three years later when seeing Jedi in a honest to goodness movie palace. The Speeder Bike scene was an IMAX like experience in that place. I've never been able to find out if that was 70mm though. I regret selling all my local newspaper SW clippings to a collector in the 90's now, as it would probably settle it.