Picked this up today, a 2001 TRB-5II. Seems like a nice bass. Still getting the feel for it, and I don't have an owner's manual. Can anyone please explain what functions the knobs are? I have them labeled 1 thru 5. Number 1 is volume, figured that one out all by myself. All four of the others have detents and are EQ? Also, I'm a little confused that there seems to be only one volume for two pickups. Thank you.