Neil Rieck
Waterloo, Ontario, Canada.
https://neilrieck.net
Caveat: This demo occasionally breaks at this hobbyist site.
If you notice any problems then please send me an email here: n.rieck@bell.net
Additional information for inquiring minds
- Signal Overview
- NO HARMONICS: the tranverse flute comes the closest to producing a pure sign wave with no harmonics
- ODD HARMONICS: reed instruments tend to involve square waves
- ALL HARMONICS: plucked strings tend to involve saw-tooth waves
- FFT Overview
- This FFT (Fast Fourier Transform) demo converts signals from the time-domain (think oscilloscope) to the
frequency-domain.
- FFT is based upon the Fourier Series which can convert any complicated signal into a series of sine
and cosine waves
- The Fourier series was first
published by Joseph Fourier
in 1822 (original work purportedly done in Egypt while serving under Napoleon)
Note: Daniel Bernoulli and Leonhard Euler worked on this branch of mathematics before Fourier, but did not
publish (or properly publish)
- The Fast Fourier Transform
was first published in 1965 by J. W. Cooley and John Tukey while working at the research division of IBM
Note: While working on a theory for planetary orbits, Carl Gauss proposed a solution very close to the 1965
FFT publication.
- video:
https://www.youtube.com/watch?v=nmgFG7PUHfo (24 min)
- video:
https://www.youtube.com/watch?v=iOsGkk63NfE (9:47 min)
- Source Code: