Continuity mistake: In the start of the scene when Kramer tells Elaine that the armoire got stolen. When Elaine walks in from the right side she walks right past the armoire, and it still has the two blue straps on it so it's the same one. The gaffe seems to have been edited out in some versions. (00:09:50)
Continuity mistake: When Jerry finds The Soup Nazi's recipes in the armoire he hands Elaine at most 4 pieces of paper, but when the shot changes to Elaine the number of recipes in her hands has increased dramatically.
Answer: Composer Jonathan Wolff used a synthesizer, although in seasons 7-9, a real bass is used in addition. Wolff also recorded himself making hundreds of mouth noises, pops, and slaps to add to the synthesized bass licks so that each episode has a different theme. The only real "back-story" is Jerry Seinfeld was having trouble coming up with a theme song and talked to a friend who happened to know Wolff. They wanted to avoid that cheesy late 80's sit-com theme song and Wolff came up with what we enjoy now. Jonathan Wolff has also talked about this further in interviews, recently Reed Dunela interviewed him, so for a fuller account of his story; check out "The Wolff of 116th street".
Bishop73