Via StarWars.com:

On May 21, 1980, Star Wars: The Empire Strikes Back made its theatrical debut. To celebrate the classic film’s landmark 40th anniversary, StarWars.com presents “Empire at 40,” a special series of interviews, editorial features, and listicles.

Inside Ben Burtt’s home office, he’s flipping through a notebook from his time working on Star Wars: The Empire Strikes Back in search of the name of the farm where he recorded the sea otter behind the bleating vocals of Hoth’s tauntauns and a bathtub full of raccoons for Dagobah’s unseen wildlife. Among the copious notes and audio tapes from his more than four-decade career is a detailed record of the nine months Burtt, the sound designer on the film, and his team spent on road trips across the United States where they recorded everything from a squeaky dumpster lid in Burtt’s yard to a lion feasting on an animal skull. More than a quest to create the soundscape to convey the otherworldly ambiance of Dagobah and so many other locations, vehicles, creatures, and sounds in the Star Wars sequel, it was also the chance to capture more than 1,000 individual audio elements to create the basis for what would become Lucasfilm and Skywalker Sound’s audio effects library.

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