megaphone

A megaphone is a cone-shaped device used to project and amplify voice so that it can be heard over a larger distance. In its simplest form, it is an acoustic horn that redirects sound waves in a way that increases the perceived loudness without any electrical power.

There are two broad categories of megaphones. Acoustic megaphones are passive devices consisting of a horn or funnel through which sound travels; they do not require power. Electronic megaphones incorporate a microphone, an amplifier, and a speaker, usually powered by batteries or a rechargeable supply. Some electronic models include volume controls, built-in sirens or alarms, and optional wireless accessories.

The term megaphone derives from Greek roots meaning “large sound.” Historically, devices such as speaking trumpets and horns were used to project a voice in large spaces, on ships, or on stage. With the advent of amplification technology, electronic megaphones became common for public addressing, crowd management, and outdoor events, and the term has remained in wide use.

Uses and contexts for megaphones include management of crowds at events, guiding tours, sports and cheerleading, emergency and safety communications, and demonstrations. They are chosen for portability, immediacy, and the ability to address individuals at a distance in noisy environments. In formal settings, their use may be regulated to protect bystanders from excessive sound and to minimize disruption.

Safety and etiquette considerations include avoiding sustained high volume to protect hearing, aiming the device away from nearby listeners when possible, and observing local regulations governing loudspeakers in public spaces.