The use of DSP in creating Guitar Effects
DSP is playing a bigger and bigger role in sound processing and one of the main areas that it is making an impact is with effects for electric guitars. Digital processing provides more flexibility and a wider range of effects for sound than analog processing.
In order to process the sound of an electric guitar and apply an effect to it, the analog signal needs to be digitized. This can be done by sampling the signal at a high rate. Next, the fourier transform of the sampled signal needs to be obtained. Since we are interested in changing the way the signal "sounds", we need to be able to shift/attenuate/amplify different frequency components of the signal. Once we have the fourier transform, we can start applying some effects to the sound.
Effects like flanger, wah, distortion, chorus, and reverb deal with the manipulation of the components of the sound at different frequencies. Some require attenuation, some require shifting and some require amplification.
Once all the manipulation has been done to the signal in the frequency domain, the inverse fourier transform is taken and the signal is coverted back to analog to be played through an amp.
