and stability problems, and need to
be recalibrated before every use.
In my case, I turn the
theremin's power on, let it stabilize
for about an hour at room
temperature, and then run through
a process of tuning to bring the
theremin into stable operation. As
long as power remains on, the
theremin is quasi-stable. However, if
power is removed, the tuning
process would need to be
performed again. This is quite a
pain and limits the usefulness of my
theremin. The Zeppelin Design
Labs Altura Theremin MIDI
Controller (shown in Photo 2 and
described in this review) takes a
different approach altogether.
First, instead of using a quasi-stable oscillator whose pitch is
modified by the player’s hand
capacitance, it uses sonar range
finder modules to ascertain the
position of the player’s hands.
Secondly -- and equally important --
the Altura theremin doesn't
produce any sound of its own.
Instead, it creates MIDI events that are passed onto
externally connected MIDI devices like a synthesizer or
MIDI sound module. The synthesizer interprets the MIDI
events and produces the actual sound.
For this review, I connected the Altura theremin to a
Roland GAIA synthesizer and to an Alesis QS- 8
keyboard/synthesizer. Both worked
well. It could also be connected to
the MIDI Buddy project I described
in the February 2015 issue of Nuts
The advantage of Zeppelin
Design Labs approach, of course, is
the analog circuitry of a traditional
theremin is replaced with digital
circuitry in the form of a
microcontroller, resulting in an
instrument that is stable every time
it’s powered up, and doesn't need
calibration before being played.
Some might say a disadvantage
of this device is that it doesn't make
any sounds on its own. I would
counter that argument with the fact
that the Altura theremin can be
made to sound like any instrument
the attached synthesizer can
produce: from a piano to a trumpet
to bag pipes to a nylon string guitar,
to even sounding like a flying
saucer — making this instrument
much more flexible in what you can
use it for.
Plus, with the proper use of
Portamento (the ability to glide smoothly between notes),
the Altura theremin can emulate the classic sound of an
analog theremin as well.
Building the Kit
The Altura theremin kit I used for this review arrived
well packaged and
damage free. The
kit itself was fully
contained in a
plastic sack as
shown in Photo 3.
Photo 4 shows the
bags of parts and
Photo 5 shows the
parts laid out for
for putting the kit
together are online
instead of being
delivered on paper
with the kit, and for
the most part are
very well written
42 March 2018
Figure 5. Parts laid out for assembly.
Photo 4. Bags of parts (the bag at the top
holds the parts for the acrylic case).
Photo 3. The theremin kit package.