Spikeh said:
I don't really wanna play about with my truss rod in case I snap it :*(
so loosen it first instead of tightening it... carefully
Wait, OK, right, you're worried. what bass do you have?
My recommendation is to give it to an expert, but then you'll never become an expert without that first step.
The truss rod is there, in essence, to add the stiffness the neck needs to counteract the string tension, right?
so, logically, slackening it (anti-clock) will let the strings win the game, so you'll get concave bow in the neck. tighten it too much (clock), and you get the opposite, which means the middle of the fretboard is touching the strings and the height at neck-end and nut is huge.
so there's the deal, right. tighten it if you need the headstock backwards (towards your body), loosen it if you need the headstock forwards (away). think of the fight between strings and truss.
Many people say to take your strings off first and use a straight-edge. I don't usually bother, as long as the thing is well in tune, then you can use the strings as straight edge.
fret the #1 fret, and fret your highest (20, 22, 24, whatever) . look in the middle of the neck. what's the gap at the 7th or 8th fret?
if it's high, tighten the trussrod (very, very slightly, a 1/4 turn is a long way). if it's touching, slacken it off, then give it some time to rest (the wood doesn't immediately spring back). with each adjustment, give it time to rest. it's wood, not elastic.
after each adjustment, play the thing all the way up the neck on every string, then look down the neck like you're sighting a rifle. Buzz could be a too-low action or it could be a bowed neck. The trick is to get the neck straight(er), and adjust the bridge up and down to get the best height you can. it takes some experience. most players have some bow in the neck, but it's very, very slight. that's where the experience thing comes in, knowing how much bow is good and so on. the good guys are ninjas at this, I'm just a roadie who knows the mechanics of it.
Anyway, some (cheap) basses have a short trussrod and are slightly doomed if a bow comes in where you can't adjust it. Good ones are trussed all the way
my personal bass runs with a very, very slight bow in the neck. I slap it, so I don't want it to be too sensitive. A jazz player may be flatter than me, so consider your style and don't forget to consult other sources. I'm not a setup ninja by any means, but I still do my own setups and setups for my mates, and they're OK-ish. ultimately, you're the player, so you're the judge.
all the same though, paying someone else means you have someone else to blame. think about that.
