A preamplifier (preamp), as its name suggests, is an amplifier which precedes another amplifier.

The second amplifier is typically a power amplifier (power amp). In this example, the job of the preamp is to amplify a low level signal, perhaps from a microphone or pickup, to line level and to apply any necessary equalization and tone control .

A preamplifier is an electronic amplifier designed to prepare an electrical signal for further amplification.

Preamplifiers may be:

• in a separate housing.
• incorporated into the housing or chasis of the amplifier they feed.
• mounted in other items of equipment, such as microphones and electric guitars.

Examples are:

• the integrated preamplifier in a foil electret microphone.
• the first stages of an instrument amplifier.
• an audio mixing desk.
• a masthead amplifier used with television receiver antenna or a satellite receiver dish.