User Manual

5
2) Truss rod cover / Truss rod adjustment
Truss rod cover:
The truss rod cover of an Alien acoustic bass gives you - when needed - quick access to the truss rod. You’ll need a flat
screwdriver to unlock the integrated latch mechanism.
Truss rod adjustment:
A neck is set up correctly if it has a slight forward bow. You can easily verify this by pressing the lowest string at the 1st and last
fret and measuring t
he distance between the fret and the string at the 7th fret: it should read between 0.06 and 0.02“. This value
is independent from the action (height) setup of each individual string.
Turning the truss rod key clockwise (direction A) will tighten the truss rod and give the neck a back bow. Turning the truss rod key
counterclockwise (direction B) will loosen the truss rod and give the neck a forw
ard bow. These adjustments should be done in
small steps because the neck’s reaction is not instantaneous. You should check the results after approximately one hour and
probably check again the following day. Readjust the truss rod if needed.
A change in humidity, particularly during the changing of seasons or during strong weather fluctuations, is when one should pay
attention to the neck’s setup and the corresponding truss rod adjustment
direction A = neck with a back bow
direction B = neck with an up bow
B
A