The Straightness of the Bass Neck
The straightness of the bass guitar's neck is commonly called relief. The neck bends upwards (called up-bow), or it can be straight, or it can bend backwards (called back-bow).
Two things cause the neck to bend:
- the tension of the strings pulling the neck upward
- the truss rod pulling the neck backward
The bass strings put many pounds of tension on the neck of your bass guitar. Think of it like a bow as in bow and arrow.
The truss rod is a metal rod inside the neck of your bass. The rod can be tightened or loosened. As it is tightened, it exerts more pressure on the neck forcing it to bend backward in the opposite direction of the string tension. When loosened, the truss rod relieves the pressure adding relief (up-bow).
Always be careful making truss rod adjustments. If you over-tighten it, you can make it snap and ruin your bass neck!
You can sight your neck by holding the body of your bass and looking from the bridge toward the nut. (See picture.) Sighting your neck will give you a quick idea of how much relief is in your neck.
Your neck needs at least a slight amount of relief so that the strings don’t buzz against the frets.
Strings vibrate in an elliptical pattern. That is, they vibrate more widely in the center of their length. So, a little relief is needed for them to not hit the frets. If your neck is straight or back-bowed, the strings may rattle against the frets causing unpleasant fret buzz.
Next: Bass String Height
Back to the Bass Setup Guide