Effects loop
Encyclopedia
An effects loop is a series of audio effects unit
s, connected between two points of a signal path; usually between the pre-amp and power amp
stages of an amplifier circuit, although occasionally between two pre-amp stages. The two principal uses of effects loops are in recordings and in instrument amplifiers.
There are two main advantages of an effects loop. The first is that generally effects sound clearer and are more pronounced when the input signal is sent through a preamplifier
prior to being affected. In addition to this, the tone of a guitar amplifier is generally more defined if the guitar is going direct into the input of the preamplifier. The second advantage is to match impedances
of equipment. For example, most guitar rack equipment works better at line-level, and not instrument level. By placing the effects after the preamp, signal loss due to impedance mismatch is avoided.
Most guitarists use floor pedal effects between the guitar and the amplifier, or they use rack effects through the amplifier effects loop. Recently, amplifier manufacturers have been including a level/gain control with the effects loops to allow for the use of floor pedals through the effects loop; rather than in-line between the guitar and amplifier. This allows for more tonal control of the amplifier.
Effects unit
Effects units are electronic devices that alter how a musical instrument or other audio source sounds. Some effects subtly "color" a sound, while others transform it dramatically. Effects are used during live performances or in the studio, typically with electric guitar, keyboard and bass...
s, connected between two points of a signal path; usually between the pre-amp and power amp
Audio amplifier
An audio amplifier is an electronic amplifier that amplifies low-power audio signals to a level suitable for driving loudspeakers and is the final stage in a typical audio playback chain.The preceding stages in such a chain are low power audio amplifiers which perform tasks like pre-amplification,...
stages of an amplifier circuit, although occasionally between two pre-amp stages. The two principal uses of effects loops are in recordings and in instrument amplifiers.
There are two main advantages of an effects loop. The first is that generally effects sound clearer and are more pronounced when the input signal is sent through a preamplifier
Preamplifier
A preamplifier is an electronic amplifier that prepares a small electrical signal for further amplification or processing. A preamplifier is often placed close to the sensor to reduce the effects of noise and interference. It is used to boost the signal strength to drive the cable to the main...
prior to being affected. In addition to this, the tone of a guitar amplifier is generally more defined if the guitar is going direct into the input of the preamplifier. The second advantage is to match impedances
Electrical impedance
Electrical impedance, or simply impedance, is the measure of the opposition that an electrical circuit presents to the passage of a current when a voltage is applied. In quantitative terms, it is the complex ratio of the voltage to the current in an alternating current circuit...
of equipment. For example, most guitar rack equipment works better at line-level, and not instrument level. By placing the effects after the preamp, signal loss due to impedance mismatch is avoided.
Most guitarists use floor pedal effects between the guitar and the amplifier, or they use rack effects through the amplifier effects loop. Recently, amplifier manufacturers have been including a level/gain control with the effects loops to allow for the use of floor pedals through the effects loop; rather than in-line between the guitar and amplifier. This allows for more tonal control of the amplifier.