Complex sentence: In contrast to the guitar or bass, the Stick is set up with very little relief in the fretboard: "i.e.," it is very flat, compared to a guitar, which has a slight bow.
Split into simpler sentences: In contrast to the guitar or bass, the Stick is set up with very little relief in the fretboard. In other words, it is very flat compared to a guitar, which has a slight bow.