Intonation Adjustment - Yamaha BB2005 Owner's Manual

When the string gauge and/or bridge height is changed, or the
truss rod is adjusted, it is usually necessary to reintonate the
bridge saddles. If the bass plays out of tune in the higher reg-
isters, this adjustment is needed. Check each string in the fol-
lowing way:
To check intonation, compare the harmonic tone (12th fret) to
the fretted tone (12th fret). Because the 12th fret is the midway
point between the nut and the bridge, a harmonic tone one
octave higher than the fretted tone can be generated. This is
done by barely touching the string directly above the 12th fret
(left hand) and simultaneously plucking the same string (right
hand). If the fretted tone is exactly the same pitch as the har-
monic tone, no adjustments to the bridge saddles are neces-
sary. However, if the fretted tone is higher in pitch (sharp) or
lower in pitch (flat) than the harmonic tone, apply the appropri-
ate adjustment as shown below. Repeat the same procedure
for each string.

INTONATION ADJUSTMENT

If the fretted note is pitched higher than the harmonic, turn the
corresponding saddle adjustment screw clockwise, increasing
the active string length.
Conversely, if the fretted note is pitched lower than the har-
monic, turn the corresponding saddle adjustment screw coun-
ter-clockwise, reducing the active string length.
When lower
than harmonic
5
When higher
than harmonic