Have you ever wanted to build devices that react to audio, but have been unsure about or even intimidated by analyzing signals? Don’t worry! This guide is an overview of applying the Fourier transform, a fundamental tool for signal processing, to analyze signals like audio. I’ll show you how I built an audio spectrum analyzer, detected a sequence of tones, and even attempted to detect a cat purr–all with a simple microcontroller, microphone, and some knowledge of the Fourier transform.
Continue on to learn some background information about the Fourier transform.
Make a robot friend with Adafruit’s CRICKIT – A Creative Robotics & Interactive Construction Kit. It’s an add-on to our popular Circuit Playground Express, FEATHER and other platforms to make and program robots with CircuitPython, MakeCode, and Arduino. Start controlling motors, servos, solenoids. You also get signal pins, capacitive touch sensors, a NeoPixel driver and amplified speaker output. It complements & extends your boards so you can still use all the goodies on the microcontroller, now you have a robotics playground as well.