Steve, it's not that hard.
Tune your bass to pitch.
Hold it by the body (DON'T be a dork and set the butt on the floor and put one finger under the headstock and sight down the fingerboard, wrong way to do this) in a playing (horizontal) position.
Look from the tailpiece end down the fingerboard. The strings, natch, will form a laser-straight line. If you look, they will cast shadows on the fingerboard. You should see a slight dip around the middle length of the fingerboard, with the shadows closer to the fingerboard at both ends. In other words, the strings' shadows should form just the slightest curve along the length of fingerboard and frets.
Take that image in your mind and put it together with what your hands are feeling.
Basically, if it's buzzing in the middle, there is not enough relief in the neck, it's too straight. If it's buzzing at either end, there's too much relief, or the nut or bridge are too low. If it's one side or the other the bridge and/or nut is low that side.
That's a VERY basic primer, but may be enough.
I know a six-sting may seem to be more daunting, but set-up is the same regardless of how many strings.
The strings basically vibrate in 'jump-rope' patterns, not just side-to-side in a flat plane. What we're after is to find that 'compromise' between enough relief/string height and what feels best to YOU. There is no empirically correct, rosetta-stone set of values that work for all basses and all players: No two axes adjust identically (wood, after all) and no two players have the identical feel they're after.
It takes a little while (well, half a forever in my case) to learn the interplay of relief, string height, and feel. But Alembics are almost singularly perfect vehicles to learn set up practice: An adjustable nut, a one piece bridge, and the twin-truss rods are a great lab to teach this to yourself. Understand that on a basic PBass or most anything else, you have to fill or replace the nut to change height there. The bridge would have individual height adjustment on each saddle. The truss rods could even require pulling the neck bolts to get at the truss rod on old-school Fenders. We get to skip ALL of that.
If all else fails, WRITE DOWN how many turns you moved this or that: That way you can always put it back !
And remember to deal in small increments: Any axe that is already playable is rarely more than half a turn away or a fraction of an inch away from being spot-on, NEVER two or three whole turns on this or that adjustment.
As always, I'll cop to stealing all of this from Dan Erlewine's EXCELLENT book, 'The Guitar Player's Repair Guide', available like most good things from Stewart McDonald (
www.stewmac.com). No home should be without it !
I learnt this as I got real tired of trying to explain to really good guitar techs WHY I wanted my bass to play like a Les Paul or a Strat, 'who would ever want a bass with low action?'. Sheeeesh . . . . . who wouldn't ?
Believe me, if I can do this, ANYBODY can.
J o e y
