Preamplifier

A preamplifier, also known as a preamp, is an electronic amplifier that converts a weak electrical signal into an output signal strong enough to be noise-tolerant and strong enough for further processing, or for sending to a power amplifier and a loudspeaker.

An ideal preamp will be linear (have a constant gain through its operating range) and have high input impedance (requiring only a minimal amount of current to sense the input signal) and low output impedance (when current is drawn from the output there is minimal change in the output voltage).

It is used to boost the signal strength to drive the cable to the main instrument without significantly degrading the signal-to-noise ratio (SNR).

Three basic types of preamplifiers are available: In an audio system, they are typically used to amplify signals from analog sensors to line level.

Preamplifiers are often integrated into the audio inputs on mixing consoles, DJ mixers, and sound cards.