What Is the Purpose of a Preamplifier?

When setting up a recording system, instrument and amplifier or home stereo system, you may need to employ a preamplifier to ensure that you are sending the best possible signal to your speaker system. By knowing how a preamplifier works in these different situation you will be better prepared to purchase and set-up your musical and audio equipment.

Purpose

A preamplifier is used to increase a low-level signal between an instrument--or audio player--and the speaker system. The preamp, as it is often called, can be built into the amplifier or a separate piece of equipment.

Equalization

Preamplifiers can also adjust and amplify tone and signal equalization, also known at EQ, depending on the make and model of the unit.

Home Audio Systems

In terms of home audio systems, a preamplifier may only be used to adjust volume. It also may be used to switch between audio sources, so no amplification is produced.

Location

A preamplifier can be located as a part of the amplifier itself, as a separate unit, or mounted within a microphone, turntable or instrument such as a guitar or bass.

CD/DVD

Preamplifiers can also be found within computer hard drives and are used to boost the signal between the computers CD/DVD player and the speaker system.

Resources

• Preamplifier Buying Guide