Modelling and Digital Simulation of Audio Circuits
Ioannis Syggelakis
Abstract
Nowadays music is inextricably linked to technology. There is a huge industry of electronic products that provide the right tools for musicians to produce their work. The circuits of these devices can produce sound, or process sound, changing it in a musically pleasing way. With the advancement of technology, analog products that were popular in the past are being phased out of the market, but musicians still require them for specific artistic purposes. Many streams of music are inextricably linked to specific colors of sound that come from these devices. In this work we study methods that exist for the effective simulation of audio circuits in real time. Today there are digital type guitar effects that reproduce through various techniques the behavior of analog effects. The problem with these is that they follow approximative methods. As a result the character of the analog effect is lost. Instead, this work applies a more detailed, physical approach to modeling them. More specifically, we deal with analog audio distortion circuits. The behavior of these circuits can be accurately characterized by their schematic and by the models of their components. So having the above we can create a model that can accurately simulate the behavior of the analog circuit in digital form. If this simulation can be done efficiently and with low latency, then the unique sound produced by these specific audio circuits can be maintained in digital form. This way we can have all the advantages of digital systems while maintaining the character of analog.