In this chapter, we’re going to build a celebrated mechanism, the looper. The looper is used widely by guitarists and other instrumentalists, even by people beatboxing. It enables you to gradually build complex sounds out of a single instrument or a voice. There are plenty of loopers on the market, even cheap ones, but this chapter will guide you through the process of building one. Once you understand how it works, then you can customize it to a great extent, making a looper that would either be very expensive as a commercial product, or one that includes features that are not present in the loopers that you can find on the market.