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Megaphone

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EXPERIMENT: MEGAPHONE vs GLASS

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How To Use a Megaphone 📣

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Megaphone Review Pyle PMP53in 50 watts large loud ready to GO.

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EXPERIMENT: MEGAPHONE in CAR EXHAUST

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Pyle PMP30 Professional Hand-Grip Type Megaphone Bullhorn with Siren | Quick Demonstration

A megaphone, speaking-trumpet, bullhorn, blowhorn, or loudhailer is usually a portable or hand-held, cone-shaped acoustic horn used to amplify a person’s voice or other sounds and direct it in a given direction. The sound is introduced into the narrow end of the megaphone, by holding it up to the face and speaking into it, and the sound waves radiate out the wide end. A megaphone increases the volume of sound by increasing the acoustic impedance seen by the vocal cords, matching the impedance of the vocal cords to the air, so that more sound power is radiated. It also serves to direct the sound waves in the direction the horn is pointing. It somewhat distorts the sound of the voice because the frequency response of the megaphone is greater at higher sound frequencies.