The Seinfeld theme music is one of the most fundamental aspects of the show that you probably never really noticed.
As Wolff describes it, Jerry Seinfeld tends to deliver his jokes in a certain cadence and rhythm, and the theme of the series was designed to work at that pace.
By doing this, Wolff could make the music hold for laughs, accentuate a punch line, or punctuate a scene.
While it may sound the same during the opening and closing of a given episode, Jonathan Wolff composed different music for each installment of the series to correspond with whatever stand-up routine bookended the episode.