The Empire Strikes Back’s Battle Of Hoth Had The Help Of The US Army

Burtt went on an extended excursion to various military bases where he knew weapons were being tested and carried along his recorder. According to this interview, he was able to capture plenty of explosions and firearms that would eventually be remixed into the weapons fire for his sci-fi picture. He was essentially allowed to build his own sound effects library that was unique to “The Empire Strikes Back.” In Burtt’s words: 

“We spent two weeks going out with the US Army to record all of their weapons. It was like being in basic training, except I didn’t have to take orders. The Pentagon Department of Defense arranged for us to travel around and go to different army bases where we did lots of weapons — artillery, small arms, shoulder-launched missiles. And all of that munition — the ricochets, the bullet fly-bys, explosions — became the core material for the snow battle.”

Of course, it wasn’t just a matter of recording explosives and firearms, but distorting the audio in a way that would make them sound distinctly “Star Wars”-like. In one instance, he slowed down the sound of a bullet bouncing off of a metal plate and morphed it into a fantasy laser blast. Yes, he had to get close. No, it wasn’t safe. He knew that. Burtt said: 

“You could take a ricochet of a bullet that we recorded and you could slow it down to become a really interesting laser, or an ion cannon or something like that. […] But looking back at it, you’d be hard-pressed to get that kind of open access today to military activity because of the liability. […] We had some close calls, where bullets were hitting the ground near us and passing overhead. But we got some good sounds!”

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