Doors Opening from The Original Series, by Lee
In Star Trek: TOS, when a door opens, you can’t help but to notice it. Although it starts with a subtle sliding sound, it ends with an obnoxious and unmistakable SQUEAK.
(This is a pretty bizarre clip; I recommend watching the whole thing after reading the rest of this post)
Why such a loud door sound on a starship? I can’t imagine that sliding doors back in the 60’s were actually that loud. But such a sound does fit with the “starship as a submarine” metaphor proposed by Belinkie. In an environment where hull breech means certain death, the ship needs to be sealed nice and tight. Think about doors on a submarine. Each one has a spinny handle which is used for, you guessed it, sealing off a compartment in the event of a hull breach to keep the water out. On the Enterprise, imagine if any given part of the ship experiences some sort of air leakage. How do you keep the air inside a given room? By sealing it…with the doors. So every time the door opens a little seal is being broken. Hence the squeaky sound.
But the sound of the door is more than just a sign of its utility. It’s also a story telling device. Think about it. EVERY TIME someone comes into a room, you hear this substantial sound effect. It’s an announcement, a heralding, of someone new arriving into a scene, typically the bridge. You know how, when you’re reading Shakespeare, and you come across the stage directions that announce that someone has entered the scene?
Enter ROSENCRANTZ and GUILDENSTERN
Enter RICHARD III
Enter THE DRAGON
Etc. Just like when you see the word “Enter,” when you hear the SQUEAK of the door, your brain prepares for a shift. Someone new is here. Things are about to get interesting.