Micro-Tonal Midi Synthesizer

Occidental music is based in the equal temperament scale, a 12 note scale made by equal frequency relations between consecutive notes and restrained to double the frequency every 12 notes. However there is an amazing amount of scales equaly important which were used (some of them) before we settled in this equal temperament scale. They are still in use though more for experimentation than for commercial use.

A lot of investigation has been done about microtonal music, ie: music dealing with different tones to the actual scale. Among the more known "well temperamented" scales stand out:

• Werckmeister temperament (invented by Andreas Werckmeister)
• French Temperament Ordinaire
• Neidhardt
• Kirnberger
• Vallotti (invented by Francesco Antonio Vallotti)
• Young
• Pythagorean tuning
• Just intonation
• Meantone temperament
• Regular temperament
• Equal temperament (this is the one used today)

All these scales are based in dividing such scale in 12 notes relating the frequencies of thirds or fifths in order to achieve (through frequency relationships) a different sound effect to the listener.

Then the idea come up of using the synthetizer to deal with these scales taking advantage in the "easy tuning" of the actual synth's oscilators. This has resulted that such scales can be realized easily, allowing the creation of original performances.

However a scale is of special importance. This scale, though invented some years ago, has not received the  attention it deserves. it's what is called The Thirteenth Sound (invented by mexican musician and theorist Julian Carrillo). This scale was the first to break the 12 note paradigm (so the name thirteen sound) making possible to have scales of whatever size come into play. More used scales are 24, 48 or 96 notes to a scale (this one the Carrillos' prefered). The scale is made by dividing a semitone, from an equal temperament scale, in 2, 4, 8 or 16 equal subtones ("micro-tones").

For some time this scale has lacked of use due to the dificult tunning any natural instrument requires. But with the advent of synthesizers this problem is not longer an issue and this scale can come to life again. There are a bunch of compositions for the thirteenth sound and music celebrities like Leopold Stokowsky, Jean-Pierre Rampal, Bernard Flavigny, Robert Gendre and Reine Falchot have performed thirteen sound musical compositions.