Go ahead, and look at the chords I put down for this jazz line. Please, don't be afraid and run off. These are all chords you are going to have deal with if you want to be a jazz bassist, someday I hope to be one too. But I do know a few things.

First off, don't be intimidated. Chords like AminorMajor7 may look intimidating, but it's only Aminor with a G# added to to it. And G#'s aren't scary.

Second, there is no need to try be a jazz bass god or godess from the start. Take it slow, and play a lot of root notes (in case you are really a beginner in chords, a root note is the lowest note in the chord, for example, the root note in Aminormajor7 is 'A'. Quick pop quiz what is the root note in, Gmaj7(-5)(9)(#11)(b13)? Yeah, it's G. Doesn't matter what you add on to it, it's still the same). Root notes are something that will always be alright to play, hardly anyone is going to notice that you are just root noting chords.

Third, and finally, just keep playing. If you hit some "bad notes" keep playing, what the hell try make it seem you were trying to sound dissonant. Now, take a listen to the line, and I will explain my note choice on the next page... I know that is why you are here. Don't Be Afraid To Root Note