Early on in Star Wars: The Last Jedi, R2-D2 tries to get his disillusioned former master Luke Skywalker to join the fight against the First Order with what Luke calls a "cheap trick" - replaying the hologram that started Luke's journey in the first place. But it turns out, a lot of work went into making that hologram sound like it had been accumulating dust since A New Hope.
Speaking to The Hollywood Reporter, Lucasfilm's supervising sound editor Matthew Wood - nominated at this year's Oscars for The Last Jedi - revealed that while the clip of Carrie Fisher herself was from the original tape recording Lucasfilm's archives, the team took a decidedly analogue approach to making it look dated and worn down.
In order to make Leia's speech feel like it's decayed a bit from sitting around in R2's memory for over 30 years, the team re-recorded a new copy of the message on an actual tape... and then beat the crap out of it:
Then, rather than doing a digital process on it, we recorded it to an analogue piece of tape - people might not know what that is anymore - but we recorded it on that piece of tape a bunch of times then dragged it through the dirt at Skywalker Ranch. We crumpled it, crushed it, threw it in a lake, rubbed rocks on it, distressed it and tied it to a car and drove it around.
A few crumplings later, and you have one authentically old-sounding piece of dialogue ready to be fitted into a similarly-old-looking hologram. Sometimes the easiest moviemaking tricks work best!