Continuity mistake: When Elaine and her new boyfriend are eating in the restaurant, her bangs are to the side. The shot goes to a close-up of her boyfriend, in the next shot her bangs are across her forehead. Then in the next close-up of her face, her bangs are back to the side.
Continuity mistake: When Elaine is sitting with Puddy in the restaurant when they get back together, the amount of wine in Elaine's wine glass keeps changing.
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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