# acoustic to electro optical frequency (sound to color) (Composition by dust)

 Author: dust License: Public Domain Date: 2012.11.17 Compatibility: 10.6, 10.7, 10.8 Categories: Required plugins: (none)

so im taking a class and i was in the need to create an, ai bot for a game etc... i thought it would be interesting to make the ai hear as well see via ray cast. the idea being to id a player by its fundamental harmonic frequency as well locate a player spatially and get me various empirical data like the players direction, distance and doppler velocity etc.. then store this post-priori data and then sort by a priori threat level tag etc...

thinking it would be very convenient to have a frequencies wave length that was equal to 1 meter and also having the players material color equal to the corresponding acoustic frequency, i found some interesting results. seeing i wanted to identify an object by its frequency and color i decided to figure out the best harmonic tuning and temperament to use. trying with Kepler harmonics mundi, pythagorean, Euler monochord, and equal temperaments, i decided to go with a base pythagorean tuning system.

now the issue with what is the most harmonic interval system has been a debate for centuries. the Keplerian interval fascinated me. so there is the new age solfeggio proposal of 528Hz and the standard 440hz. Kepler's interval was 256 and at a 432Hz tuning middle c is 256Hz with octaves of 512, 1024 etc..... those numbers seemed very familiar...

so the conjecture is that 432Hz is the most harmonic and geometric etc... knowing i needed to use Kepler to solve for things in my game i found many interesting coincides with his tuning like middle c lining up the earth rotation and one octave being 360 degrees etc.. f sharp being the diminished 5th from c 256 is called the devils interval and out lawed etc.. more on this later.

being the person i am, naturally i wanted to hear the devils interval and see what color it is etc.. as it subsequently turns out there is no color for this interval as it is in the infra-red non visible range. this devils interval was interesting and very close to my goal of a 1m wavelength. the wave length of 256Hz at -110 degrees celsius is 1m but that didn't seem a very logical. this devil interval was still geometrically intriguing as in conical spiral form.... C=256 corresponds to the perihelion of the ellipse C=512 corresponds to the aphelion F corresponds to the semi-latus rectum F-sharp corresponds to the semi-minor axis G corresponds to the semi-major axis

so this all very fascinating. seeing this a computer model i could tune things and model them any which way i wanted so i decided 666 sounded more like the devils interval. as it turns out if you multiply the f sharp devils interval by a 666Hz or f you get the Kepler interval of 256Hz. if you take the diminished 5th or devils interval of 666hz which is Ab and substitute it for theta degrees celsius the speed of sound becomes 333 m/s with a frequency of 333Hz and a wave length of 1 meter which turns out to be A 421.5Hz tuning. this is the tuning that mozart found to be the most harmonic which makes sense a he was known to have perfect pitch at the age 3. in mozart's tuning the f sharp is also not visible but on the opposite uv fringe of the visible spectrum instead of infra - red from 432Hz.

numerically this is all interesting and coincidentally spooky but the idea of a devil intervals is silly and explains why they don't play purple haze in church. it is perplexing and impossible to map midi as in pythagorean tuning the diminished 5th (devils interval) - Ab and augmented - 4th - G# are the same note on the midi keyboard. so for the midi feature of this patch i decided to be like church and exclude the devils interval and display the augmented 4th instead. in the end all this non sense did actually make it easier to determine location and velocity using standard fft analyses.