Fast Fourier Transformations not only allow you to perform tasks in the field of audio. They allow anyone to analyse the noise of a turbine or the voltage levels of vehicle electronics and, in many cases, draw conclusions about rotational speeds and the like. The Maixduino board with its K210-SoC, available from Elektor, is not only suitable for experimentation with neural networks but can also be used for fast, real-time FFT, as we show in this article.