Knowledge (XXG)

Megaphone

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337: 353: 230: 80: 520: 72: 88: 325: 391: 365: 280: 532: 400: 562: 294:'s instrument 200 years later. In 1878, Edison developed a device similar to the speaking trumpet in hopes of benefiting the deaf and hard of hearing. His variation included three separate funnels lined up in a row. The two outer funnels, which were six feet and eight inches long, were made of paper and connected to a tube inserted in each ear. The middle funnel was similar to Morland's speaking trumpet, but had a larger slot to insert a user's mouth. 189: 672: 544: 96: 64: 253:
have been credited with inventing megaphones around the same time in the 17th century. Morland, in a work published in 1655, wrote about his experimentation with different horns. His largest megaphone consisted of over 20 feet of copper tube and could reportedly project a person's voice a mile and a
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were first becoming popularized, women used these amplifying technologies during the roll call of participants. Later, portable electric megaphones extended this equalizing influence to outdoor events. Some protest leaders use electric megaphones to speak to an outdoor crowd or to other protesters.
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With Edison's megaphone, a low whisper could be heard a thousand feet away, while a normal tone of voice could be heard roughly two miles away. On the listening end, the receiver could hear a low whisper at a thousand feet away. However the apparatus was much too large to be portable, limiting its
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Twenty years earlier, Kircher described a device that could be used as both a megaphone and for "overhearing" people speaking outside a house. His coiled horn would be mounted into the side of a building, with a narrow end inside that could be either spoken into or listened to, and the wide mouth
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on the side, with a trigger switch to turn it on. In use, the device is held up to the mouth, and the trigger is pressed to turn it on while speaking. Other larger versions hang from the shoulder on a strap, and have a separate handheld microphone on a cord to speak into, so users can address a
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to convert the audio signal to sound waves again. Although slightly heavier than acoustic megaphones, electric megaphones can amplify the voice to a higher level, to over 90 dB. They have replaced acoustic megaphones in most applications, and are generally used to address congregations of
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For decades, film directors have used megaphones to communicate with their cast and crew on sets where it was hard to hear. The acoustic megaphone became an iconic clichéd symbol of a movie director, although modern directors use electric megaphones. A major contributor to this cliche was
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Portable megaphones are widely used for crowd management and mass communication. When needing to communicate information or directions to a large crowd of people in one place, an electric megaphone is valuable when other public address systems are not present.
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crowd without the instrument obscuring their faces. A vast array of modern electric megaphones are available to purchase, and characteristics like power, weight, price, and the presence of alarms and shoulder straps all contribute to a consumer's choice.
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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
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Governments can pass laws restricting the use of electronically amplified megaphones. In the US the ability to use a megaphone in public can be restricted to certain decibel levels, time of day or banned in residential neighborhoods. However, under the
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and popular music to give retro and often humorous effects. A recorded voice or music can be processed to give it a "megaphone" sound effect without using an actual megaphone, by audio recording decks and software. In recording software like
208:(5th Century B.C.) wearing masks with cones protruding from the mouth in order to amplify their voices in theatres. Hellenic architects may have also consciously utilized acoustic physics in their design of theatre amphitheaters. 275:
are stones around the central place with holes shaped in a megaphone's profile. Their purpose is today unknown, but as local guards can show, it is possible to amplify a human voice loud enough to hear it across a large area.
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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
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are credited with first using acoustic megaphones in routines in 1898. Since then, cheerleaders have relied heavily on acoustic megaphones during performances at sporting events. Generally, female cheerleaders would use
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The distinctive distorted sound of a human voice amplified by a megaphone is widely recognized, from its use in train and bus stations and sports arenas. Applied to music, it gives the sound of an antique acoustic
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is an important aspect for cheerleading, so experts recommend the use of acoustic megaphones not only to increase the volume of sound, but also to protect performers’ voices in the process.
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Morland favored a straight, tube-shaped speaking device. Kircher's horn, on the other hand, utilized a "cochleate" design, where the horn was twisted and coiled to make it more compact.
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An article about restrictions that may legally be imposed on public protests (including use of bullhorns), by Daniel L. Schofield, S.J.D., published in the November 1994 issue of the
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The shape of the megaphone directly affects the range of projection; narrower horns compensate for lower power by concentrating sound more sharply than wide horns.
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Prescott, George B. Bell's Electric Speaking Telephone: Its Invention, Construction, Application, Modification, and History. New York: D. Appleton &, 1884.
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were developed in the early 1920s, vacuum tube versions were too heavy to be portable. Practical portable electric megaphones had to await the development of
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chief named Iscouakité using a megaphone made of birch bark. The text of the illustration says that he is addressing his soldiers through a birch bark tube.
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The initial inventor of the speaking trumpet is a subject of historical controversy. There have been references to speakers in
892: 390: 308:, although the cheap, light, rugged acoustic megaphone is still used in a few venues, like cheering at sporting events and 625: 441:, an electronic device that amplifies the human voice like an acoustic megaphone, using electric power. It consists of a 998: 279: 739: 364: 35: 1016: 875: 630:. Many of his films were biblical epics set on vast outdoor sets that required communication with hundreds of 598: 531: 499:
Handheld versions are shaped generally like the old acoustic megaphone, with a microphone at one end and a
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A small sports megaphone for cheering at sporting events, next to a 3 inch cigarette lighter for scale
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in 1947. In 1954, TOA Corporation developed the EM-202, the world's first transistorized megaphone.
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use. George Prescott wrote: "The principal drawback at present is the large size of the apparatus."
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Mills, Mara. "When Mobile Communication Technologies Were New." Endeavour 33.4 (200111111: 141-47.
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people wherever stationary public address systems are not available; at outdoor sporting events,
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at pools and beaches where the moisture could damage the electronics of electric megaphones.
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while male cheerleaders, with loud booming voices, would project cheers through megaphones.
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Prior to the invention of the electric microphone, early pop singers sang with a megaphone.
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You Can't Say That!: The Growing Threat to Civil Liberties from Antidiscrimination Laws
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Since the 1960s, acoustic megaphones have generally been replaced by electric versions
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Montgomery, Henry C. (1959). "Amplification and High Fidelity in the Greek Theater".
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Woman using a small handheld electric megaphone at a demonstration in Portugal.
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This article is about the amplification device. For the chemical compound, see
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An electric megaphone is used at a protest (Black Lives Matter, July 2021)
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An electric megaphone is used at a protest (Black Lives Matter, June 2020)
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The EM-202 made by TOA Corp., the first transistorized handheld megaphone
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An electric megaphone is used at a protest (Fight Trump, February 2018)
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is one of the few fields that still uses acoustic megaphones.
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deal primarily with the United States and do not represent a
41:"Bullhorn" redirects here. For the G.I. Joe character, see 991:"Controlling Public Protest: First Amendment Implications" 27:
Portable or hand-held device to amplify voices and sounds
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German soldier using a megaphone to command troops, 1930
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to wake recruits at an American training camp in 1947
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A sailor using a megaphone to amplify the sound of a
889:Go! Fight! Win!: Cheerleading in American Culture 457:to increase the power of the audio signal, and a 172:, an electrically-powered amplifier and a folded 537:Waist-slung megaphones with separate microphones 123:is usually a portable or hand-held, cone-shaped 872:Technology and Women's Voices: Keeping in Touch 290:The term 'megaphone' was first associated with 268:trumpet of special design was the Sengerphone. 52:"Loudhailer" redirects here. For the song, see 679:The examples and perspective in this section 283:A late 19th-century speaking trumpet used by 8: 976:(2003 ed.). Cato Institute. p. 31. 549:Man using megaphone with separate microphone 241:using megaphone to communicate over distance 153:of the megaphone is greater at higher sound 697:, or create a new section, as appropriate. 836:"TOA | From 2010 | TOA History" 713:Learn how and when to remove this message 445:to convert soundwaves into an electrical 164:described above has been replaced by the 762: 577:Besides their practical implications, 358:German lifeguard with megaphone, 1969 258:projecting through the outside wall. 7: 492:which followed the invention of the 437:An electric megaphone is a handheld 942:"The Megaphone Effect in Radio Ads" 904:Carrier, Justin, and Donna McKay. 415:Electric megaphones use a type of 160:Since the 1960s the voice-powered 25: 373:jazz singer using megaphone, 2007 809:"SENGERPHONE-Y by Len Mullenger" 670: 542: 530: 518: 398: 389: 363: 351: 335: 323: 54:Loudhailer (Maaya Uchida single) 618:, director of epic movies like 893:Bowling Green State University 813:www.musicweb-international.com 222:, circa 1675 to 1682, shows a 1: 45:. For the type of tree, see 854:"Megaphone & Bullhorns" 693:, discuss the issue on the 1033: 876:Routledge & Kegan Paul 740:Long range acoustic device 271:Additionally, in ruins of 131:a person's voice or other 51: 40: 36:Megaphone (disambiguation) 29: 1000:Law Enforcement Bulletin 645:. It has been used in 599:University of Minnesota 569:using megaphone in 1922 583:public address systems 579:public address systems 570: 479:public address systems 287: 242: 201: 100: 92: 84: 76: 68: 34:. For other uses, see 906:Complete Cheerleading 891:. Bowling Green, OH: 860:on September 1, 2012. 773:The Classical Journal 565:Silent film director 564: 472:street demonstrations 439:public address system 282: 232: 191: 98: 90: 82: 74: 66: 56:. For the album, see 972:Bernstein, David E. 887:Hanson, Mary Ellen. 691:improve this section 647:radio advertisements 621:The Ten Commandments 503:at the other, and a 477:Although electronic 32:Megaphone (molecule) 481:have existed since 58:Loud Hailer (album) 43:Bullhorn (G.I. Joe) 923:"Cecil B. DeMille" 870:Kramarae, Cheris. 662:Legal restrictions 571: 381:Electric megaphone 288: 251:Athanasius Kircher 243: 237:, 1684, shows man 235:Athanasius Kircher 218:on page 14 of the 202: 166:electric megaphone 162:acoustic megaphone 151:frequency response 138:acoustic impedance 101: 93: 85: 77: 69: 947:Houston Chronicle 908:. Champaign, IL: 723: 722: 715: 627:The King of Kings 589:As of the 2010s, 557:Impact on society 468:political rallies 16:(Redirected from 1024: 1017:Audio amplifiers 978: 977: 969: 963: 962: 960: 958: 937: 931: 930: 919: 913: 902: 896: 885: 879: 868: 862: 861: 856:. 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Index

Loudhailer
Megaphone (molecule)
Megaphone (disambiguation)
Bullhorn (G.I. Joe)
Bullhorn Acacia
Loudhailer (Maaya Uchida single)
Loud Hailer (album)





acoustic horn
amplify
sounds
acoustic impedance
vocal cords
matching
frequency response
frequencies
microphone
horn loudspeaker
amplify

Codex canadensis
Louis Nicolas
Ancient Greece
Louis Nicolas
Codex canadensis
Native American

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