Neck And Truss Rod - Peavey Spectrum Bass Owner's Manual

Neck and Truss Rod

Every Peavey bass guitar features an adjustable truss rod inside the neck. Truss rods
allow for adjustments in the neck to accommodate changes in string tension caused
by humidity, changing string gauges or tuning. As the backbone of your instrument,
the truss rod should always be adjusted first during instrument setup. (Peavey rec-
ommends that you enlist the services of a qualified technician to make the required
truss rod adjustments on your instrument. Improper adjustment may damage your
neck and void your Peavey warranty.) To gain access to the truss rod, look for a 
mm or  mm allen wrench adjustment screw either at the end of the neck near the
body or at the opposite end near the headstock. Note that some bass guitars may
require neck removal to gain access to the neck pocket truss rod. The goal of truss
rod adjustment is to create the correct amount of bow in your bass guitar's neck to
facilitate optimal playability.
To check the neck's bow, hold the guitar in normal playing position and follow
this procedure for both outside strings (highest and lowest strings). Fret and
hold the string at the first fret, while fretting and holding the same string with
your picking-hand thumb (where the neck and body meet, typically around the
16th fret). Then, stretch your picking hand index finger as far as you can to fret
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