ABSTRACT
FFT is an acronym for “Fast Fourier Transformation,” named after the mathematician Jean-Baptiste Joseph Fourier. The purpose of a Fourier Transformation is to transform waveform (impulse response/waveform) into frequency; a methodology implemented in many kinds of audio analysis. The basis for the Fourier transformation is the fact that an infinite series of harmonics can describe every (infinite) periodic signal. FFT is in principle a sampled version of the continuous spectrum. In FFT analysis, there is always the same distance in cycles between the individual lines in the spectrum. Since it is usually preferred to view a frequency scale with a logarithmic axis, this means that the lines of the spectrum are shown increasingly closer to each other at higher frequencies. Most audio analyses are or can be, based on FFT. Even though FFT provides linear frequency resolution, FFT applies to logarithmic frequency divisions with a relative bandwidth, such as octave analyses.
