One of the reasons the bank shootout in Heat sounds so incredible is that much of the gunfire you hear was actually recorded on location.
Michael Mann wanted to keep the natural sound of the blanks echoing through the streets of Downtown LA. The buildings created this canyon-like effect where every shot just exploded through the city and kept bouncing around.
They tried replacing some of it with cleaner gunshot effects afterwards, but it just didn’t have the same impact.
That raw sound is a huge part of what makes the scene feel so intense. You don’t just hear the gunfire, you feel how loud and chaotic it would be to actually be standing there.
Still one of the greatest shootouts ever put to film.