What does an amplifier do in audio equipment?

An amplifier in audio equipment serves the primary purpose of increasing the strength of audio signals. This function is essential because audio signals, especially those produced by microphones or musical instruments, often start off as weak electrical signals. An amplifier takes these signals and boosts their power, making them strong enough to drive speakers or headphones without distortion.

When an amplifier increases the strength of these signals, it also allows the resulting sound to be heard more clearly and at higher volumes without losing quality. This is crucial in various audio applications, from home theater systems to live concert setups, where sound needs to be projected over distances or through large crowds.

While enhancing sound quality and reducing noise can be important aspects of audio processing, the essential role of an amplifier is primarily about signal strength. Recording audio signals does not pertain directly to an amplifier's function, as this involves different equipment such as recorders or digital interfaces. Therefore, the correct answer identifies the fundamental characteristic and purpose of an amplifier in the context of audio equipment.