signal processor is a device (or
circuit) which alters the audio
signal in some non-linear fashion. By
that definition, a simple fader, level
control or amplifier IS NOT a signal
processor. An equalizer, filter, compressor,
phaser, delay line, or other
sound altering device IS a signal
processor. In this section of the handbook
we go into some detail on a
variety of common signal processing
devices, providing some historical
perspective, how it works information,
and limited notes regarding applications
and use. The one product category
we have omitted here is the
crossover network (or frequency
dividing network), which is covered in
detail in Section13.7 (most people
would not consider a crossover network
to be a signal processor, although it
certainly does alter the signal).