So, to the business of setting up a Bass Guitar. Tuning aside – do start with that first! – string height is the number one adjustment on a bass. There are all sorts of reasons that string height adjustment is needed, from changing string type and fret wear to changing weather conditions and playing style.
Before we start, there’s no point adjusting the string height if the neck relief (the bow in the neck adjusted by the truss rod) is out. For now we’ll assume it is good, check out the upcoming post on neck relief for more on that. The neck pitch also needs to be right too, but I’ve yet to come across a bass where the neck pitch (angle of the neck to the body) is adjustable, so we don’t need to go there.
The two signs of incorrect string height are:
- Fret buzz when playing – deeply unpleasant rattling that generally doesn’t go along with more playing styles!
- Having to press the strings ‘too far’ – the strings end up a long way from the neck and the bass becomes harder to play.
The string height, or action, is set by the bridge saddles that hold the strings. Older basses have flat head (slot) screws that enable you to adjust the setting, newer basses tend to use allen (hex) keys. Turning the screws further in raises the action, unscrewing them (anti-clockwise) lowers the action, letting the strings get closer to the frets and the pickup(s) – something to watch, you don’t want the strings too close to them!
The shape of the bass fretboard has a slight curve to it, drawn along and imaginary radius. The bridge saddles will generally follow the same arc. Severe changes to the bridge height can affect the intonation (the internal tuning if you like), but little tweaks shouldn’t be a problem. You can check the intonation later.
The super bright out there will have realised that the string height is also affected by the nut at the other end of the string. Generally the setting at the nut is fine out of the factory. Over the years the nut can wear down, which usually means time for a new one. In a few decades of bass playing I’ve never needed one, but I’ve never owned a bass older than me, so it isn’t out of the questions. The nut is not generally a do-it-yourself change. Likewise if the nut does happen to be too high, it is time to call in an expert. Some basses dispense with nut and have a so called “zero fret” where it would have been. This is personally my preferred set up, but generally only seen on higher-end basses (although it doesn’t mean that a bass is higher end).
Fret a string at the highest fret. Obviously there’s never going to be any fret buzz here (there aren’t any more frets!), but it is the point on the neck where the action is highest. Slide down and play at the 12th fret. If there’s fret buzz here, you’ll want to raise the string, just a little. Try fretting at different frets until you are reasonably buzz free. For a lower action, there will be some buzz, so don’t fret (as it were). If you get buzz in one place but not others, this is a sign of uneven fret wear. Again, time to head to an expert to have the frets refinished.
Adjust the height of each string, and don’t forget to check the open strings too. That’s it. You’re done.