How Does
How Do Guitar Effects Pedals Work?
Audio Signal
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The audio signal from a guitar is an electrical waveform. Vibrations from an electric guitar's are changed into electrical signals by its pickups, then sent through a cable to an amplifier, recording device or an effects pedal. A guitar effects pedal reads the electrical audio signal either directly from the guitar or from the output of another piece of audio equipment. The signal is then sent to the pedal's inner workings for processing.
Modulation
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The tone-shaping processes in an effects pedal are generally referred to as modulation. Most modern pedals modulate an audio signal through a series of transistors set into a circuit board. Digital effects processors convert the electrical signal to digital code to shape the audio, then return it to electrical signal for output. Other effects, such as distortion and some vintage reverb pedals, use analogue devices, such as vacuum tubes, to change signal properties.
Output and Bypass
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Once a signal has been processed, it is sent through an output jack into another instrument cable. Digital processors sometimes include digital outputs, which send the audio as code without converting it back to electrical signal for recording or further processing.
When a pedal's effect mode is turned off, the audio is routed around the modulation phase and sent directly to the output. Pedals which have a dedicated route for unchanged audio are referred to as true-bypass effects. These units often have cleaner tones when disengaged than pedals which use the same signal path for modulation and bypass.
eHow Article: How Do Guitar Effects Pedals Work?
