Difference in amplitude from the same source using FFT

Posted by Anders on Stack Overflow See other posts from Stack Overflow or by Anders
Published on 2010-04-05T10:52:04Z Indexed on 2010/04/05 10:53 UTC
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Hi,

I have a question regarding use of FFT. Using function getBand(int i) with Minim i can extract the amplitude of a specific frequency and do pretty maps of it. Works great.

However, this is a more of a curiosity question. When i look at the values extracted from playing the same song two twice using the same frequency (so the amplitude should be identical) but i get very different values - why is this?

0.0,0.0,0.0,0.0,0.0,0.08706585,0.23708777,0.83046436,0.74603105,0.30447206
0.0,0.0,0.0,0.0,0.0,0.0,0.0,0.08706585,0.4790409,0.9608221,0.83046436,0.74603105

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