See the movie of dsPIC FFT
The following are movie clips which show you how FFT works on the dsPIC board.

(1) classic_a_1k.wav : 1kHz of sine wave overlaps on a classic music. The fifth bar is the spectrum of 1kHz.

(2) classic_a_2k.wav : 2kHz of sine wave overlaps on the classic music.

(3) classic_a_500.wav : 500Hz of sine wave overlaps on the classic music.

(4) Blues : You may see the fingers on the organ slide from high to low position at the last of this clip.

(5) Boogie (old-fashioned) : There is almost no low or high tone. So only the spectrum of mid-range looks active.

(6) Flute : Spectrum is narrow and relatively tall for a flute and piano.

(7) Koto : The contrast of loudness and silence is clear for a koto, that is Japanese traditional guitar.

(8) Romantics : Fingers on a synthesizer show up clearly as spectrums.

(9) Piano : The sound is silent but the spectrum is very tall for a piano.

(10) Rap : The spectrum of "scratch" is tall and very fast.

(11) Pop-Rock : Bars are converged in the area of low tone. Electric guitar's sound is not so interesting in terms of spectrum.

(12) Strings : The spectrum of string instruments tends to be multiple sine waves. The spectrum says there are three strings on it (?)


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