## Isolate a single bin of an FFT

This example shows how to isolate a single FFT bin, as opposed to displaying the entire spectrum. The example uses **fft~** instead of **fftin~**, but the principle is the same.

This example shows how to isolate a single FFT bin, as opposed to displaying the entire spectrum. The example uses **fft~** instead of **fftin~**, but the principle is the same.

The Fast Fourier Transform (FFT) is a mathematical procedure for converting a time-domain signal (such as a sound wave) into an equivalent frequency-domain representation (the soundâ€™s spectrum). The inverse transform (IFFT) reverses that process. The Max object **pfft~** allows you to encapsulate an FFT and IFFT (with the objects **fftin~** and **fftout~** respectively) and program some sort of frequency-domain processing (alteration of the spectrum) between the two.