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Effects |
Effects are devices designed to modify a signal in some way − usually in a way that improves the interest or "fullness" of the sound. This section describes some of the more commonly used effects.
For information on how effects units may be connected into a system, please see glossary entries Serial effects unit and Parallel effects unit.
Note that this page does not include descriptions of dynamics processors such as a compressors, expanders, limiters, noise gates or de-essers − see their respective glossary entries.
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Often known as 'reverb', this is an effect unit which simulates the ability of a room to cause a sound to die away slowly when the source of the sound ceases abruptly. Reverb units are useful in reducing the 'dryness' of a sound.
As rooms differ in the manner and degree to which they exhibit this effect, such effect units usually provide some control over the type and extent of the reverb effect which they produce. The more sophisticated digital units now available generally allow selection from a number of reverb types, for example types simulating various different sizes of room and types simulating the old analogue reverb effects such as spring-line and plate units.
Gated reverb is an effect which has the facility to automatically cut off the reverberation effect when the input signal falls below a specific level.
This is an effect unit which simulates a natural echoing of the sound, or which provides an artificial effect of a similar nature. Most units have the ability to provide a single echo or multiple echoes. See also Delay.
Delay is another name for an echo unit, because an echo is a delayed (and, usually, somewhat modified) copy of the original sound. Such a unit may also be used to provide a delayed version of a signal to 'secondary' speakers which are situated some distance in front of the main speakers (in a very large hall, or outdoors); this enables the sound heard from the secondary speakers to be synchronised with the sound heard from the main speakers − the latter having been delayed in travelling through the air to reach the location of the secondary speakers. Approximately 30 milliseconds of delay is required per 10 metres of distance between the main and secondary speakers (see Speed of sound).
This is an effect unit which modifies a signal in such as manner as to simulate the presence of several additional sources of the same (or similar) sound, all operating in unison − as in "a chorus of voices".
This is an effect that is sometimes used with guitars to improve the 'interest' of the sound. It may be adjusted to give a wide range of effects, a common one being a slow 'sweeping' sound.
This is similar to a more extreme version of the phase effect; a rather harsh 'sweeping' effect used with electric guitars to to help give a 'heavy metal' type of sound, and for other 'special effects' purposes. (It gained its name from the fact that it was originally produced by mixing the sound with a tape-recorded version of it that was slowed down by means of friction applied to the flanges of the tape spools.)
Generally used only with electric guitars, an effect that simulates a distorting guitar amplifier. Previously known as 'fuzz'.
Generally used only with electric guitars, a more subtle version of the distortion effect, less rich in the higher harmonics. It simulates an overdriven guitar amplifier.
This page last updated 20-Jul-2007.