Scotty Greene asks about tuning a xylophone.  I've had really
great results with the xylophones I've made by double tuning them.
Most people don't realize that you can tune not only the fundamental
tone but also the overtones.  This is one area that separates
xylophones from marimbas.

The first overtone of a marimba is tuned an octave above the
fundamental while the same overtone on a xylophone is tuned an octave
and a third above the fundamental.  This is why xylophones sound bright
and marimbas sound mellow.

First I rough tune the fundamental by removing material from the back
center of the bar.  I remove only enough to tune the bar about 10 cents
or so sharp.  Removing material from the center of the bar lowers the
pitch while removing material from the ends raises it.  To properly
hear the fundamental tone of the bar, it should be grasped at its nodal
point which is a point 2/9ths of the length of the bar from either end.

Next I tune the first overtone which can be accomplished by removing
material from the back of the bar roughly half way between the center
of the bar and the nodal points.  This has the effect of lowering the
first overtone.  If you remove too much you can raise the overtone by
removing material at the nodal points.  To make the bar speak the 
first overtone, grasp it firmly with two fingers in the very center
and strike the bar at its end.

Once the overtone is tuned, I then go back and fine tune the
fundamental by removing a little more material from the center of
the bar to bring it down to proper pitch.  You'll find that removing
material from the center of the bar has a big effect on the fundamental
but almost no effect at all on the first overtone so the overtone will
remain in tune even after you've tuned the fundamental.

It may seem like a lot of extra work but tuning bars this way just
makes them sing!

Bruce Newman - From the Oregon Coast where winter has finally hit
with a vengeance!