Development of a triple input musical instrument tuner using Yin algorithm

In music, it is important that the instruments sound harmonic and reproduce sound in a repeatable and universal manner. Humans have difficulty in distinguishing very similar sounds, therefore, a device capable of doing so is very useful. The tool used for this is called an instrument tuner. There is a huge variety of such devices in the market, usually capable of detecting sound and frequency from specific instruments, due to the way sound is produced. Musicians that play different instruments must own multiple tuners to suffice their needs. This article details the development of an optimized pitch detection device, running on an Android smartphone, capable of detecting and processing sound signals emitted by different kinds of instruments, with frequencies ranging from 27.5 Hz to 4186 Hz in a non-expensive manner.