Simple Explanation

A device that boosts weak audio signals (such as those from microphones or low-output sources) to a level that can be sent to a power amplifier or other components in an audio system.

Concise Technical Definition

A preamplifier (or preamp) is an audio component that accepts low-level input signals from sources like microphones, CD players, or turntables, and amplifies them to a level suitable for further amplification by a power amplifier. Some preamps also include additional features such as volume control, balance, bass management, equalizers, and digital signal processing (DSP).

Layman-Friendly Analogy

Think of it like a volume knob at the start of an audio system. It takes quiet sounds (like from a microphone or turntable), makes them louder, and prepares them to be heard through speakers.

Industry Usage Summary

Preamplifiers are essential in audio systems, particularly in professional audio, home theater systems, and music production. They route and amplify signals from various sources (e.g., microphones, turntables, CD players) to a level that can be processed by amplifiers and other devices. Many audio/video (AV) receivers combine preamps with amplifiers in one unit, while standalone preamps may offer higher-quality sound processing and additional features like tone control, bass management, and DSP.

Engineering Shortcut

A device that amplifies low-level input signals to line-level, typically used to route and control various audio sources.

Full Technical Explanation

A preamplifier (preamp) is the first amplifier in an audio system's signal chain. It accepts low-level input signals, such as those from microphones (mic-level) or other low-output sources (e.g., CD players, turntables, or tape recorders), and increases the signal to a higher line-level that can be processed by power amplifiers or other devices. In addition to amplification, preamps may include source switching, volume control, and tone adjustments. Some models incorporate bass management, equalization (EQ), and digital signal processing (DSP) for more refined sound control. In AV receivers, the preamp and power amplifier are often combined in a single unit, providing both control and amplification in one device.