ANS synthesizer

The ANS synthesizer is a photoelectronic musical instrument created by Russian engineer Evgeny Murzin from 1937 to 1957. The technological basis of his invention was the method of graphical sound recording used in cinematography (developed in Russia concurrently with USA), which made it possible to obtain a visible image of a sound wave, as well as to realize the opposite goal—synthesizing a sound from an artificially drawn sound spectrogram.

In this case the sine waves generated by the ANS are printed onto five glass discs using a process that Murzin (an optical engineer) had to develop himself. Each disc has 144 individual tracks printed onto it, for a total of 720 microtones (discrete pitches), spanning 10 octaves. This yields a resolution of 1/72 octave (16.67 cents). The modulated light from these wheels is then projected onto the back of the synthesizer's interface. These are arranged in a continuous swath vertically, with low frequencies at the bottom and high frequencies at the top.

The user interface consists of a glass plate covered in non-drying opaque black mastic, which constitutes a drawing surface upon which the user makes marks by scratching through the mastic, and therefore allowing light to pass through at that point. In front of the glass plate sits a vertical bank of twenty that send signals to twenty amplifiers and bandpass filters, each with its own gain adjust control. It is akin to a ten-octave equalizer with two knobs per octave. The ANS is fully polyphonic and will generate all 720 pitches simultaneously if required (a vertical scratch would accomplish this).

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