microphone preamp

microphone preamp

An electronic circuit or stand-alone device that boosts microphone input. A mic preamp is used to adjust the volume of the signal sent to powered speakers or an amplifier. Unlike a phono preamp, there is no standard equalization stage, although there may be a gain control to balance different inputs to the same level. See phono preamp.

Single-Channel Mic Preamp
Because microphones have different output levels, the GAIN dial is used to balance various inputs so that the OUTPUT volume will always be the same. At the very left is a high impedance (Hi-Z) input port, typically for a guitar or bass instrument. (Image courtesy of Warm Audio LLC, www.warmaudio.com)