This sketch demonstrates very simply how you might use the inverse FFT to modify an audio signal.
Press 'f' to perform the forward FFT, then press 's' to scale the large frequency band.
Now press 'd' to take the inverse FFT. You will see that the wave form has a smaller amplitude.

You might wonder how we knew which band to scale. You should read this blog post about calculating FFT averages for the answer to that question.

Source code: ScaleBand

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