To start, I did try to check the instruction post stickies, but couldn't find what I was looking for. I'm pretty new to the bass and trying to distinguish between a Bb7 and a Bb6. I'm playing R-3-5-7 through a simple jazz measure and I think i'm doing it wrong. I'm pretty sure a B7, for example, would be a mixolydian form, and the Bb7 would just be a major flat, but Bb6 has me stumped. So, all of that for a simple question, but any help is appreciated.

Well,you need to know about chord symbols in order to play jazz. I'm sure you can find some links and infos here. It might be confusing at first because nothing is perfect and chord symbols are not perfect but there are some rules you'll need to learn and apply. I suggest that you start with the Major scale and learn how to build chords from it.

Good luck,

SB

Bb6 = Bb D F G
The "6" is the 6th degree of the scale.
If you put the G in the bass, you'll have a Gm7 chord.

Bb7 = Bb D F Ab
The "7" is the 7th degree of the scale.

I hope this helps out a little bit.
Joe

Yes, that was very helpful. Thanks for the fast reply, Joe. Take care.