http://www.woodreview.com.au 51
PROJECT
How to Make
a Tongue Drum
Native species are combined, tweaked and tuned to create a musical
instrument you can vary in countless ways. Story by Raf Nathan.
T
ongue drums are a relatively simple instrument that
acts by way of ‘tongues’ or keys which vibrate with a
box that acts as a resonator.
Many designs for these can be seen on the internet.
The simplest and most common way to make them is to
cut the keys with a jigsaw, although some people now use
CNC routers to cut the key outlines. The keys can be
cut straight as rectangles or you may add a flourish by
shaping the keys in a more organic way.
Most of the tongue drums you see around the lower price
end are not tuned. Some will have a random tuning as they
have been made without planning the lengths of the keys,
and they can sound good. However higher quality drums
will be tuned, and this makes a huge difference to the
sound and playability.
The tongue drums you see in music stores are tuned to a
pentatonic scale, and these have a clear, bright sound. Those
made by Schlagwerk are particularly good and use padauk
for the keys and what looks to me to be maple for the box.
I used blackwood for my first tongue drums and the
sound isn’t bad but better are my current favourites which
are made from Tasmanian celery top pine and myrtle.
The myrtle drum is pitched higher whilst the celery pine
has a lower tone.
Two things are critical to sound production: rubber feet
on the base and using quality sticks. Store bought sticks
can come with balls of various hardnesses and these affect
volume and brightness.
You can make your own sticks with dowel and toy shop
rubber balls glued to the ends but these are rather soft and
the sound produced is somewhat muted. Professional grade
marimba sticks are a better choice. Naturally shop made
sticks are preferable and I am still trying to source suitable
rubber for this purpose.
Making the drums
The key size I have settled on is 32–35mm wide and
18mm thickness. You will need to do the math on the
actual cut dimensions and there are no fixed sizes as
far as the overall dimensions go. The drums shown
here are around 420mm long and 140mm wide and
130mm high.
My research uncovered very little about how to build
a tuned tongue drum. I did discover that apparently
a key length difference of 6% raises or lowers the
sound by a full tone. However different woods will
have different sound characteristics and the 6% factor
is not reliable. My own experimentation says 10mm
difference in key length is sufficient to approximate
a full tone between keys.
Left: Evolving designs, the
first drums were made from
blackwood with following
ones made from celery top
pine and myrtle.