Portable megaphone for evangelism. It can use battery or electricity. It has two microphones inputs A & B. It has power change over switch Up for battery and down for electric.
A megaphone, speaking-trumpet, bullhorn, blowhorn, or loudhailer is usually a portable or hand-held, cone-shaped used to a person's voice or other 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 seen by the , 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 of the megaphone is greater at higher sound .