Signal processor

A signal processor is an device which processes signals containing information. Also analog signals with analog electronics is used, the name means mostly digital electronics circuits that processes digital signals. Most modern signal processors are either dedicated microprocessor integrated circuits or general-purpose programmable microprocessors. A DSP (digital signal processor) is an electronic device which serves the purpose of signal processing. It can be used for digital to analog conversions and vice versa.

Digital audio

In the realm of digital audio, a signal processor is a device that modifies an audio signal, either analog or digital. It can be a piece of electronic hardware or computer software. A basic example of a signal processor is a high-pass filter, which removes low frequencies from a signal.

Traditionally signal processors were electronic circuits that affected analog signals. In digital audio, signal processors can be software that alter digitized audio information. The term Digital Signal Processing (DSP) usually refers to the processors that are involved in calculating the effect a digital signal processor will have on an audio data stream. For example, HD Accel cards by Digidesign contain processors that calculate the changes to a digital audio signal.

Signal processor functions

• Equalization
• Filters
• Reverberation
• Delay
• Dynamic processing (compression, expansion, limiting, noise gating)
• Noise reduction

References

• Audio in Media, Stanley R. Allen, Thomson Wadsworth, 7th Edition, 2005. ISBN 0-534-63046-4