Signal processor

A signal processor, in the realm of digital audio, is a device that modifies an audio signal, either electric 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 file. For example, HD Accel cards by Digidesign (a leader in professional digital audio technology) contain processors that calculate the changes to a digital audio signal.

Types of Signal Processors

• 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