Here's what BB King thinks:
BB King Interview
Guitar.com: What do you look for in a bass player?
King:
One that will play what I want. That's what I look for. I'm a blues player. I like one-three, I mean I, IV and V. Them blues chords. And I want the guy to spell them out, play 'em for me where I can hear em. Of course I'd like him to have a little more knowledge, so we could, you know, everything we play is not 12-bars.
Guitar.com:
Right, you do so much more than I, IV and V, he's got to know a little more than that.
King:
But if he's good with I, IV, and V, I still can live with him because I can teach him the other. If he's good with that I, IV, and V, he's my guy. And I want him to drive. I want him to be like the drums: I want him to drive. And that's what I like in a bass player.
Guitar.com:
When you say you can teach him the rest what if the guy comes to you just playing I, IV, and V? Where do you take him from there?
King:
I'd teach him how to play eight bars. Eight bar blues has many changes. I'll teach him, that ain't no big problem. If he want to learn, I'll teach him.
Guitar.com:
Some of the jazzy turnarounds and things?
King:
I don't think of it as jazzy turnarounds, it's just different from 12-bar blues. It always kinda gets my nerve when a guy says, "I'm a jazz musician." I don't like that. Or "I'm a blues musician." I don't like that either.
Guitar.com:
You prefer to just say you're a musician.
King: Yeah. If it's something I want. For example, if I came to town, and I was looking for somebody to play, I want em to play what I want. I ain't looking for no jazz musician, I ain't lookin for no blues musician. I want the guy to play what I want. Now if he studied jazz, fine, cause most jazz musicians are better with blues than actually the blues musicians, cause they're more familiar with chords.
Guitar.com: Right.
King:
So that's fine with me. But I don't want a guy to say, "Yeah, I'm a jazz musician. I don't play them old blues." I put a X on his name. (laughs) Or "I'm a blues musician. I don't play no jazz." I put a X on his name too.