Introduction to the Wave Theremin:
If you are looking for an easy way to get acquainted with this new Theremin, we
recommend the Video Tutorial to get you started.
If you already own this Theremin, here is How to Kickstart the Wave Theremin
If you want to unlock the secrets of
this exiting new musical instrument, then read on ...
The Instrument and Mode Selector in more detail:
The Instrument Selector:
Each of the instrument settings of the Instrument Selector (natural, flute, … square) has
3 oscillators associated with. They are capable of producing the waveform of the selected
Instrument (i.e. Sine etc…) and each oscillator can be individually adjusted in pitch,
volume, pan, tone (low-pass) and fade (MIX).
Setting the instrument selector to 'SETUP' allows you to customize your Theremin, tune the
Theremin again, adjust playing range, save and recall user-settings etc…
The Mode Selector:
The mode selector works in conjunction with the instrument selector. If for example we have
the instrument 'sine' selected and we set the mode selector to 'volume' we are then able to
change the volume of each of the 3 internal oscillators individually. Parameter knob P1 will
change 'oscillator-1' volume, P2 changes 'oscillator-2' volume and P3 for 'oscillator-3'
volume. Likewise for 'pitch' , 'pan' , 'tone' etc…
If we set the mode selector to position 'main', the parameter knobs P1, P2 and P3 control
the 'main-volume' , 'main-tone' (low-pass) and the 'octave' for all instruments (GLOBAL).
The 'octave' feature allows you to transpose the whole Theremin pitch in octaves up and down.
Turning the octave up to the extreme settings will allow you to create aliasing effects and
other strange and more or less random textures and sounds. Using the 'pitch-range' adjust,
allows you to zoom into a particular aliasing sound and 'stretch it' over the Theremin
playing range … this will become clear once you gain a deeper understanding of the Theremin.
The A/B Switch:
With the 'A/B switch' , we can toggle between 2 different settings of a particular instrument
(a set of 3 oscillators). If for example we select position A and we turn only the volume
of the main oscillator up (oscillator-2 and oscillator-3 volume to zero) then we would have
created a simple sine wave Theremin sound at instrument 'Sine A'.
If we then switch to 'Sine B' with the A/B switch, we may decide to have oscillator-1 at
full volume and add a small amount of oscillator-2 and oscillator-3 volume as well. We now
hear 3 sine-waves when we play the Theremin. Each of the oscillators can be individually
panned in the stereo field (left to right) to create a broader sound image (panorama sound).
The frequencies of oscillator-2 and -3 are 'ratios' of the frequency of the main oscillator-1.
This means whenever we change the frequency of oscillator-1, the frequency of oscillator 2
and 3 will follow according to their frequency-ratio setting.
If we set the frequency-ratio of oscillator-2 to be 'two times oscillator-1 frequency' then
oscillator 2 acts like the first harmonic of oscillator 1. If you would choose a random ratio,
you are likely to get a more dis-harmonic effect.
If we set the frequency-ratio of oscillator-3 to be 'half of the
oscillator-1 frequency' then oscillator-3 acts like the first sub-harmonic of oscillator-1.
This would allow you to create a fuller Theremin sound. Toggeling between A and B would then
be like a 'Tone Switch' adding or removing the harmonics (!). You may decide to set the pitch
ratios to resemble a cord or a more bell like harmonic structure etc....
This is an experimental feature only. It allows you to fade out a particular oscillator with
increasing 'frequency' similar to a low-pass filter but instead of filtering, this is done
by controlling the volume of the oscillator. Try it … for some interesting sonic textures
Pointing the mode selector to the 'tremolo' position allows you to turn on the build in
tremolo / auto-trigger (midi) feature. The tremolo is a global effect, it is not associated
with any individual instrument directly, but is saved / recalled with all the other settings.
Parameter P1 adjusts the 'intensity' (zero = OFF), P2 selects the tremolo 'wave form' from
sine (left), triangle, rect. sine and saw to square (right) and with P3 we select the tremolo
'speed' from slow to very fast.
The tremolo is also linked to the midi Theremin and acts as a auto trigger, with trigger
velocity controlled via the main-volume.
Pointing the mode selector to the 'gate' position allows you to enable the build in gate
(external volume control). The gate is also a global effect and is not associated with any
individual instrument directly, but is saved / recalled with all the other settings.
The gate responds to a trigger pulse on the audio-input. This pulse can be from a microphone,
a drum trigger, a audio track or just a hum from touching the other end of the lead (!)
This enables you to create a beat for the Theremin from external trigger sources or adjust
the volume externally i.e. just touching the end of the trigger lead intelligently, allows
you to perfectly control the Volume of the Theremin . The gate is in effect an envelope
follower (!) Pushing the trigger button will open the gate fully for as long as the button
Parameter P1 allows you to adjust the trigger input 'gain' (zero = OFF), P2 is
'trigger-threshold' (midi only) and P3 is 'decay'.
The starting pitch of the Theremin is primarily controlled by the 'octave' setting and the
'pitch' setting of the main oscillator-1.
With the 'pitch-range' setting we can control the overall playing range of the Theremin
from 'no range' (pitch does not change) to a fraction of a semitone (useful only for
extreme aliasing settings) to multiple octaves (the more octaves, the more difficult it
will be to play a melody).
P3 is 'coarse' adjust and P2 is 'fine' adjust. P1 has a special feature (experimental),
it adjusts the 'granularity' of the Theremin pitch-control (from smooth to grainy to odd
semitones) … again … try it to find out.
The Pitch range is adjustable for each instrument (not global) !!
Resonant Filter Operation (Resonance, Noise):
The 24 dB resonant filter is implemented as a ladder style filter. It is self oscillating (when the resonance parameter is turned up high) and with increasing drive, it exhibits (by design) a certain amount of tube style distortion (even harmonics) which makes it a very musical filter.
The ‘RESONANCE’ position of the instrument selector has 3 raw generators available: saw-tooth, square and needle. Each raw generator can be independently adjusted in pitch and volume.
The ‘NOISE’ position of the instrument selector has 3 noise generators available: white noise, noise and crackle. Each noise generator can be independently adjusted in volume. Noise and crackle can be independently adjusted in pitch (kind of) as well.
The stereo inputs of the theremin are combined and added to the internal audio generators and then send to the filter input. When not using the internal audio generators (only external signal), both filter positions (‘RESONANCE’ and ‘NOISE’) are essencially identical. The resonant filter has 3 outputs: High-Pass, Band Pass and Low-Pass. Each output can be panned left/right and adjusted in volume.
Ring Modulator Operation:
The ‘MODULATE’ position of the instrument selector has 3 carrier-frequency generators available: sine, triangle and square. The carrier frequency is controlled via the theremin antenna and the octave-skip parameter. The ‘MODULATE’ position also has 3 raw oscillators available: triangle, square and needle. Each raw oscillators can be independently adjusted in pitch and volume. The stereo inputs of the theremin are combined and added to the internal raw oscillators and the mix is then send to the ring modulator input.
Ring modulation is performed by multiplying each of the 3 carrier wave forms (sine, triangle, square) with the incoming audio signal (external signal + raw oscillators). The resulting 3 output signals can be individually panned and mixed.
When not using the internal raw oscillators (only external signal), the ring modulator modulates the external signal by multiplying each of the 3 carrier frequencies (sine, triangle, square) with the external signal.
Wave Theremin - MIDI operation:
The Theremin can be set up in various ways to generate midi events, from pitch-bend
to note ON/OFF to control messages and program change messages. Each instrument can be
set up individually to perform in a particular way. Selection of midi channel and pitch
bend mode is done globally via SETUP.
Theremin Piano mode:
The Theremin is able to send note-on/off messages when triggered with the trigger-switch,
the internal auto-trigger or via external trigger input. Pitch is controlled via the
Theremin and the 'octave' parameter (Theremin-frequency * Octave + note-offset).
When triggered externally, trigger velocity is derived from the trigger signal.
Internal triggers derive the velocity from the main-volume.
Setting the note-offset allows you to align the pitch of the midi instrument with the
pitch of the build in audio oscillators.
The Theremin piano mode (Note) is disabled when in Pitch-bend mode.
Theremin Pitch-Bend mode:
The Theremin is able to send Pitch-bend messages and also note-on/off messages
(when triggered with the trigger-switch, the internal auto-trigger or via external
trigger input). Note on/off message pitch is controlled via the 'octave' parameter
and the Pitch-Bend offset (Octave * note-offset). When triggered externally, trigger
velocity is derived from the trigger signal. Internal triggers derive the velocity
from the main-volume. The Theremin Pitch-bend mode
has higher priority over piano-mode and control-message mode.
Theremin control message:
The Theremin is also able to send 14 bit midi-control messages.
The closer to the antenna we go, the higher the control value will be.
This can be used to control external filters with the Theremin. The Theremin
control messages are disabled when in piano mode (Note) or in Pitch-bend mode.
Whenever a new instrument is selected and 'instrument select' has been enabled for this
particular instrument, a program-change message is send out. To setup the program change
message, set the mode- selector to 'Instrument' (MIDI) and adjust 'instrument select / OFF'
with parameter P3. To disable the message again, just turn P3 to zero again.
Parameter Knob control message:
Each parameter knob is able to send 14 bit midi-control messages.
To setup the midi-control messages for a parameter knob, set the
mode-selector to 'Knobs' (MIDI). Adjust 'control-message / OFF'
with the parameter knob (P1, P2, P3) to select the desired message ID.
To disable the message, just turn corresponding parameter knob to zero again.
Using parameter knobs to send midi messages is in conflict with the non-midi
operation of the Theremin. Be warned…
A midi monitor program like 'MIDIMON' or 'midioxse' (free) could come in handy.
Alternative Pitch-Bend note trigger:
When not using the pitch-bend mode in conjunction with any internal or external triggers,
it is possible to automatically trigger a midi-note-on message whenever the active
Theremin region has been entered. In turn, a note-off message will be send when exiting
the active Theremin region (or antenna mute). Additional note-on messages can be triggered
via other sources as well, if required.
Using Pitch-Bend without trigger:
It is not necessary to trigger any note via the Theremin at all. Just use the pitch-bend
mode in conjunction with a keyboard and play chords, scales, etc on the keyboard and use
the Theremin as a high resolution pitch-bend 'lever' . This opens up an amazing new way
of playing the keyboard as a Theremin.
A number of different pitch-bend modes are possible:
- Theremin mode: rest at the lowest position and go all the way up
- Down only: rest in middle (neutral) position and go down only
- Full bend: rest in middle (neutral) position and go down / up
- Up only: rest in middle (neutral) position and go up only