Trivia: When Kramer is hosting the show and starts getting a little nervous about Jerry's "questionable material" he tells Newman to put on a tape and it starts playing some music while he talks to Jerry. The music that he puts on is the same music they used in the episode "The Pilot (2)" for the "Jerry" pilot.
Trivia: In the Seinfeld Finale, Jerry and George have a conversation in the jail cell about the positioning of a button on George's shirt. For those viewers who don't know or don't remember, that is why George asks, 'Haven't we had this conversation before?', because this is the same conversation that started off the series in the very first episode.
Trivia: In Jerry's dream of Leo doing pull-ups. Leo has a tattoo on his back that says "Brentano's", the name of The Bookstore Leo got caught stealing from.
Trivia: The grandson, Bobby, that ends up calling Elaine is voiced by Thomas Dekker in an uncredited role. Dekker played Bobby in s07e04, "The Wink", the sick boy in the hospital that had the Yankees signed birthday card. Dekker also appeared in s05e16, "The Stand-In", as "Son" that Mickey stands in for.
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".
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