Bass Guitar Glossary Terms
Intonation: For a bass guitar intonation refers to the length of the strings relative to the position of the frets. Bad intonation refers to the detuning that occurs when the string is stretched as it is fretted.
Piezo pickup: Certain crystals, ceramics, and polymers exhibit the phenomenon of piezoelectricity. Piezo means pressure in Greek, and piezo materials directly transform mechanical vibrations into electrical signals. Most under-saddle pickups are based on the piezoelectric effect.
Truss rod: The truss rod is a metal rod located inside of the neck. It is anchored at both ends and has an adjustment screw that tightens or loosens the tension it puts on the neck. More tension pulls the neck downward to counter bowing. Loosening the truss rod has the opposite effect. There are a variety of designs, many of which require removal of pickguard to access the adjustment screw. A few designs allow adjustment without unstringing or removing parts of the bass. Sometimes the adjustment screw is located at the top of the neck just beyond the end of the fretboard, sometimes at the headstock just beyond the nut.