| 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 (?) |