Bass set up

TheOtherDennis

I bought a second hand Ibanez GSR180, and not only is the action a bit high, especially at the bottom end, it rattles  on a lot of notes unless I fret them absolutely perfectly. Slides are a waste of time, they sound like a pissed off snake.

I tried adjusting the saddles but that makes it worse.

If I look down the neck from the head to the body, which way would I adjust the truss rod to try to improve the set up, clockwise or anti-clockwise?

Advice appreciated, otherwise I'll flip it.

Thanks.

paul_c2

Anticlockwise.....(lefty loosy)....

Reason: it sounds like the neck has none or negative relief, ie it curves with the hump at the front. And that the corresponding bridge/saddle height needs to be set very high to get it to play the first few frets, even then loads of buzzing. So....since the truss rod counteracts the string tension, you want less truss rod effect, so the string tension pulls the neck into a more straight/curves hump at back shape.

The correct way to do it is to fret each string at fret 1 (a capo really helps) and at the top fret, then look closely or take a measurement of the action at fret 8 (which is approx. the middle). If there's no gap between the 8th fret and the stings, then the neck is straight or bent backwards (ie the wrong way). I can't remember the exact dimension you want but its approx "business card thickness", which makes an ideal stand-in measuring tool if you don't have a gauge.

There's plenty of useful info on Youtube, on setting up the bass guitar.

Remember....

1. Truss rod
2. Tune guitar properly
3. Bridge height
4. Tune guitar properly
5. Intonation
6. Tune guitar properly
7. Pickup height

Then since the bridge height and (to a lesser extent) the intonation has an effect on it all, you may have to go back and tweak the truss rod again and repeat a few times until you're happy.

TheOtherDennis

Ok, fair enough, ta muchly for the info.

However, having put my capo on at the first fret, and then fretted the strings at the top fret (which is the 22nd fret on this neck), there's a gap at the 8th fret of more than a business card's width. :-S

EDIT: But that's presumably because I'm not paying attention properly, and I should adjust the truss rod, then the bridge height etc until I'm happy.

Durr.

Apologies.

TheOtherDennis

Apologies, I've just noticed this is in the Classified guitar section - can a mod please move it to the Bass section? Really sorry, not having a good day.

paul_c2

Doesn't sound right...is it consistent across all strings? Which frets buzz the most?

In any case, you can't damage a guitar by adjusting the truss rod, so you could try it, then reset the rest of the stuff, then try it again and if it gets worse, try it the other way. But if it won't stop buzzing at certain frets, or can only be stopped buzzing if the action is really high, then it suggests something else such as too much, or inconsistent fret wear, or a warped neck. I'm assuming the neck doesn't have a tilt adjustment (like, a little hole in the back of the neck plate)?

Its worth giving it a fair go to see if you can improve it, if you still have issues after a bunch of adjustment then probably the next step is to take it to a proper technician. Some of them have a rig which can check the alignment of everything using lasers, apparently.

TheOtherDennis

The bottom string buzzes the most. The buzzing kicks in around the 7th fret on that and on every fret thereafter; not till the 14th fret on the A string, but every fret after; on the 9th fret on the D string, but I can lose it with correct technique until the 14th fret; and from the 13th fret up on the G.

I've turned the truss rod roughly half a turn to the left and retuned to get it to do that. I've lowered the bridge, too, and unfretted, the height of the E string at the 12th fret is 3.5mm. With a capo on the first fret and holding down the E string at the 22nd fret, the height at the 8th fret is roughly 1.5mm.

I have an 18inch steel ruler, and if I place one end on the first fret, it touches down again on the 15th fret. I can get a business card underneath the ruler from fret 2 to fret 13.

mart

That sounds to me as if you should tighten the truss rod a bit, and raise the saddles.

Raising the saddles will raise the action, but tightening the rod should counteract that.

TheOtherDennis

I see your point, but the saddles were almost off the screws before I did anything to them.

Confused now. Don't want this to turn into another ghostwhistler thread. :-S

ICBM

If the saddles have run out of adjustment range and it's still buzzing or choking at the top of the neck, you're going to have to take the neck off to fix it. Don't worry, it's not as scary as it sounds.

Take the strings off.

Lay the bass face down on a soft towel or something on a table.

Take the screws out - it's good practice to note which hole each one comes out of, sometimes they're different lengths or the threads are subtly different due to manufacturing tolerances, and it's best to make sure each goes back in the same hole.

Carefully turn it back over while holding the neck in place, then lift the neck out of the pocket.

Check for any shims or any loose material that shouldn't be there at the inner end. Check the underside of the neck heel too in case something is stuck there.

If there is a shim etc, remove it.

If there isn't, make one for the *outer* end of the pocket from a piece of business card. About half an inch wide and nearly the full width of the pocket is about right. (Not overhanging the curved bit.)

Position it so it's directly over the two screw holes, put the neck back in place, turn the bass over while holding it, and refit the screws - turn each one gently backwards so it drops into the existing thread and doesn't try to cut a new one. You'll need to punch two of them through the card first.

Tighten everything up and restring…

If any/all of that is already familiar, I hope you don't mind .

TheOtherDennis

Not at all, @ICBM, none of that was familiar in the slightest. Thank you, I shall try that.

TheOtherDennis

So by putting a shim under the neck, raising the saddles a bit and giving the truss rod a clockwise tweak, I've stopped the rattling on all but the bottom E, and even that is much less than it was. I think the truss rod may be close to its limit, though (based on my limited knowledge - I could be wrong).

The action seems a bit high to me, though. Unfretted, it's just under 3mm at the 12th fret on the E. Is this about right? Obviously I won't get it as low as a six-string electric, but is this about right or still a bit high?

ICBM

That's about right for a bass usually.

TheOtherDennis

In which case, I shall leave it as is and say thanks very much for your help.

ICBM

If there's enough saddle height now you've shimmed it, it might even be worth trying a little higher - you don't tend to feel it as much on the low E.

Getting rid of rattle entirely on a bass can be hard sometimes - one of the problems on more lightly-built ones with thinner necks is that the string is heavy enough that it's not just the string that vibrates back and forth, the whole neck does too. (It does on any instrument really, but with a guitar it's negligible.) So as the string is moving down towards the neck, the neck is also moving up towards the string, and that can drastically reduce the clearance to the frets. It's difficult to see without a strobe light, but the movement can be quite dramatic if you do.