Polyphonic, Ondes Martenot inspired instrument
“Les Ondes Martenot” is along with the better known Theremin, amongst the first electronic instruments with the invention dating from 1928 (same year the theremin was patented). This is a quite rare instrument today and only a small number are still in working order.
Interestingly, it shares a lot of things with the theremin: it produces monophonic sounds (one note at a time), it is a continuous pitch instrument (it can naturally produces portamento between two notes, for instance like the trombone) and it also has a continous “expression” (the volume and the tone can be dynamically changed like breath or bowed instruments). Differences lie in the way the musician interact with the instrument. Pitch and expression on the theremin are controlled by the proximity of the player’s hands with two antennae. On the ondes Martenot, expression is controlled by a key on the player’s left hand and the pitch is either controlled by a sliding ring or by a piano style keyboard (it worth noting that this keyboard, is not fixed but can moved left and right, allowing for vibrato effect and bends). The Ondes Martenot was also special by the different types of loudspeakers that were connected to the instrument giving different tones.
Bølgene takes inspiration on the original Ondes Martenot with similar controls (soft key and ring) but brings some changes in terms of synthesis and by adding a polyphonic capability. Bølgene is fitted with four pressure sensitive keys, permitting to independently control the expression of four voices. Similarly to the Ondes Martenot, the pitches of the voices is controlled by the ring position with the three additional voices playing at a fixed interval with respect to the fundamental (for instance the fifth, and the thirds). This allows to produce chords where the expression of each notes can be controlled in an independant way, opening the way to very evolving sounds…