Simple Explanation

A device that makes an audio signal stronger—so it can power speakers or be heard louder.

Concise Technical Definition

An amplifier increases signal level—voltage, current, or both—to drive loudspeakers or other outputs. It typically takes low-voltage line-level input and outputs sufficient power to produce sound.

Layman-Friendly Analogy

Like turning up the volume knob on a faucet—an amplifier boosts a trickle of audio into a strong stream that can fill a room.

Industry Usage Summary

Amplifiers are found in audio interfaces, AV receivers, studio monitors, guitar amps, and powered subwoofers. They can be standalone, built-in, or part of active speaker systems. See also: Preamp, Power Amp, Instrument Amp.

Engineering Shortcut

Amp = signal booster: line-level in → speaker-level out.

Full Technical Explanation

An amplifier is an electronic device that boosts the amplitude of an input signal—either voltage, current, or both—so it can drive a load such as a loudspeaker. Audio amplifiers typically take low-voltage signals (under 2 Vrms) from sources like preamps or mixers and convert them into high-power signals for acoustic output. There are many amplifier classes (A, AB, D, etc.) and types (e.g., power amps, integrated amps, guitar amps), each optimized for efficiency, fidelity, or tonal coloration depending on the application.