Fft Wrong Value?

Randomly building a very easy sound spectrum analyzer. Given this python code: http://rosettacode.org/wiki/Fast_Fourier_transform#Python Implemented like this: import math from cma

Solution 1:

You apparently have a large DC component due to the fact that your sine wave has an offset of +0.5. If you make your sine wave have a zero mean (i.e. a range of say +/- 0.5 or +/- 1.0) then your spectrum should look better at the DC (0 Hz) end.

Note also that you have not use a window function prior to the FFT so you will get spectral leakage (a "smearing" of the spectrum) and this can exacerbate the effect of any DC component.