Long Range Acoustic Device

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The LRAD is the round black device on top of the New York City police Hummer.

The Long Range Acoustic Device (LRAD) is an acoustic hailing device developed by LRAD Corporation to send messages and warning tones over longer distances or at higher volume than normal loudspeakers. LRAD systems are used for long range communications in a variety of applications[1]including as a means of non-lethal, non-kinetic crowd control. Though they have been called "sonic weapons",[citation needed] LRADs are not inherently for military use.

According to the manufacturer's specifications, the systems weigh from 15 to 320 pounds (6.8 to 145.1 kg) and can emit sound in a 30°- 60° beam at 2.5 kHz.[2]The manufacturer also produces systems for public address and mass notification use that broadcast 360°.[3]

LRAD systems are used by maritime, law enforcement, military and commercial security companies to send instructions and warnings over distance, and can be used to initiate. LRAD systems are also used to deter wildlife from airport runways, wind and solar farms, nuclear power facilities, gas and oil platforms, mining and agricultural operations, and industrial plants.


LRAD on a U.S. Navy ship

The parameter "ka", which is the wave number multiplied by the speaker radius, is often used to characterize sound source directivity. For this source, ka=19 at 2.5 kHz, and according to the LRAD data sheet, the beam angle of about 30 degrees total is precisely what is predicted for a regular loudspeaker.[4]

Small spherical "point-source" acoustic devices follow the known inverse square law, which predicts the loss of 6 dB per doubling of distance from the source, solely due to geometric spreading. Large speakers (or large arrays), such as these, have an interference pattern in the nearfield which produces peaks 6 dB higher than the output pressure and nulls where the pressure is essentially zero.[5] The larger the speaker, and the higher the frequency, the longer the effective nearfield. The nearfield for this device is approximately 8m.[5]

LRAD operator wearing hearing protection

LRAD Corporation was formerly named American Technology Corporation.

Against protesters[edit]

An NYPD officer stands ready with the LRAD 500X at an Occupy Wall Street protest on November 17, 2011 near the city hall

An LRAD was aimed at protests of the 2004 Republican National Convention in New York City[6] but not used.

LRADs were used by the Pittsburgh PD during protests at the G20 Summit in September 2009. This was the first time it was used against protesters in the U.S.[7][8]

Israel's Ministry of Defense ordered LRADs in June 2011.[9]

LRAD was reportedly[10] used by the Oakland Police Department during the clearance of the Occupy Oakland encampment on the morning of 25 October 2011.

LRAD was present, but not used, when the New York City Police department cleared Occupy Wall Street protestors from Zuccotti Park on the morning of 15 November 2011.[11]

The Delhi Police are purchasing five LRADs for crowd control[12] while the Polish Police also acquired LRAD units in December 2010.[13]

LRAD was present, but not used because of current legal regulations during protests in Poland, including Million Marijuana March 2011 and Marsz Niepodległości (National Independence Day March) 2011 and 2012. Lacking a way to utilize the LRADs purchased to their full potential sparked an investigation suspecting corruption behind their acquisition. National Police Headquarters spokesman Mariusz Sokolowski defended the purchase of LRAD. He also stressed that the police decided to make this investment because, "We needed good sound reinforcement equipment. With numerous demonstrations and gatherings, police need a public address system that allows you to reach thousands of people."[14]

LRAD was deployed during a NATO march on May 20, 2012 in Chicago, Illinois at Michigan Ave. & Cermack.[15]

The Salisbury, MD Police Department acquired an LRAD in October 2013 with proceeds from their speed cameras.[16]

13, 18 August 2014 St. Louis County police used LRAD against protestors demonstrating the police shooting of Michael Brown in Ferguson, Missouri.[17] Reporter Mike Tobin commented while broadcasting from Ferguson, MO on 18 August, “It doesn't have the effect of crippling people. It's just loud, it's annoying, it lets you know something big and official is coming and that’s what’s happening now. They can also use it as a loudspeaker to tell people to get out of the way.”[18]

On December 5, 2014, the NYPD used a Long Range Acoustic Device (LRAD) to disperse about 100 protesters who were on the streets protesting the police killing of Eric Garner in Midtown Manhattan.[19]

The NYPD used a Long Range Acoustic Device during the Baltimore solidarity rally in Union Square on April 29, 2015. An NYPD pickup truck equipped with an LRAD parked near protesters and began broadcasting a looped warning message about staying off the streets and not blocking the sidewalks.[20][21]

The New Jersey State Police used an armored vehicle mounted LRAD on crowds denied entry to a June 7, 2015 concert after they began throwing bottles and tried to rush the gates outside MetLife Stadium.[22]

On June 26, 2015, Czech Special Forces Police may have deployed a LRAD 500X during anti-immigration and anti-Islam protests in Brno, the second largest city in the Czech Republic .[23][24]

Against pirates[edit]

On November 5, 2005, the luxury cruise ship Seabourn Spirit employed an LRAD while repelling pirates who attacked the vessel with rocket-propelled grenades about 115 km off the coast of Somalia.[25] The effectiveness of this device during the attack is not completely clear, but the pirates did not succeed in boarding the vessel and eventually fled.

The Liberian vessel MV Biscaglia was attacked on November 28, 2008. The security detachment aboard Biscaglia claimed to have used an LRAD device in an effort to repel attackers armed with assault rifles and rocket-propelled grenades. Following a one-sided shootout, the ship was seized and the unarmed security contractors abandoned ship leaving the ship and crew to the pirates.[26] The incident caused the usefulness of LRADs to be called into question by Lloyd's List.[27] In August 2013, Carl "Rocky" Mason, one of the three members of the security attachment aboard the Biscaglia during the incident, stated that an LRAD was aboard, but that he and the security attachment only had time to open the water cannons before gunfire and an RPG round forced them to abandon ship. No attempt was made to use the LRAD device during the incident.[28]

In January 2011, the Spirit of Adventure, a cruise ship sailing through the Indian Ocean, deployed an LRAD system as part of its defensive measures when being pursued by pirates.[29]

London Olympics 2012[edit]

It was confirmed by the Ministry of Defence on May 11, 2012 that an LRAD would be deployed in London during the Olympics. It was spotted fixed to a landing craft on the Thames.[30]


In February 2009, the Japanese whaling fleet operating in Antarctic waters near Australia installed LRADs on their vessels. The device was used against activists of the Sea Shepherd Conservation Society.[31] The Japanese fleet later escalated the use of LRAD, deploying it against a Sea Shepherd helicopter carrying a camera crew.[32][33] Sea Shepherd noted that they had an LRAD of their own, but as of early 2010, had not put it into use[34] other than to play a recording of "Ride of the Valkyries" in the manner of attacking U.S. Army helicopters depicted in the 1979 film Apocalypse Now.[35]


See also[edit]


  1. ^ Applications - LRAD Corporation website [1]
  2. ^ Corbett, Peter. A Modern Plague of Pirates. p. 65. ISBN 0-9562107-0-8. 
  3. ^ LRAD Corporation website [2]
  4. ^ Beranek, Leo L. 1986. Acoustics, p.132, American Institute of Physics.
  5. ^ a b Blackstock, David T. 2000. Fundamentals of Physical Acoustics, p.456, John Wiley and Sons.
  6. ^ ABC News. Technology & Science. August 25, 2004. Amanda Onion. RNC to Feature Unusual Forms of Sound: Unusual Forms of Sound to Emanate From RNC
  7. ^ Protesters Are Met by Tear Gas at G-20 Conference - NYTimes.com
  8. ^ LRAD used in residential neighborhood in Pittsburgh, Pa during the G20 summit
  9. ^ LRAD Corporation Announces Opening LRAD® Order from Israel's Ministry of Defense [3]
  10. ^ Martin, Adam (25 October 2011). "Occupy Oakland's Tent City Is Gone". The Atlantic Wire. Retrieved 26 October 2011. 
  11. ^ "Occupy Wall Street: Police use military megaphone to amplify their point to protesters". New York Daily News. 18 November 2011. Retrieved 15 February 2015. 
  12. ^ http://indiatoday.intoday.in/story/delhi-protests-delhi-police-long-range-acoustic-device-lrad-disperse-crowds/1/268600.html
  13. ^ http://oddzialprewencji.policja.waw.pl/portal/opp/173/20546/MOBILNY_LRAD500X_NA_PLYTE_BOISKA.html
  14. ^ http://www.rmf24.pl/fakty/polska/news-potezna-bron-sluzy-jako-zwykly-glosnik-policyjny-system-lrad,nId,768500
  15. ^ http://www.nbcchicago.com/news/local/nato-chicago-2012-151998815.html
  16. ^ http://www.wboc.com/story/23639955/salisbury-police-utlizing-new-lrad-system
  17. ^ http://www.stltoday.com/news/local/crime-and-courts/st-louis-alderman-says-police-pulled-him-out-of-car/article_0806541b-ed48-5d06-9267-323531ad6cf1.html
  18. ^ (http://view.vzaar.com/2007295/video (2'45" - 3'10"))
  19. ^ http://www.alternet.org/news-amp-politics/video-nypd-uses-military-grade-sonic-weapon-eric-garner-protesters
  20. ^ https://www.youtube.com/watch?v=IQ996JYzFME
  21. ^ http://www.mintpressnews.com/why-the-nypd-is-cracking-down-on-anti-police-brutality-protests/205395/
  22. ^ http://www.complex.com/music/2015/06/police-deploy-tear-gas-on-crowds-outside-hot-97-summer-jam
  23. ^ http://policejnidenik.cz/wp-content/uploads/2015/06/DSC_00613-1024x702.jpg
  24. ^ http://policejnidenik.cz/do-brna-se-kvuli-demonstracim-sjeli-policiste-ze-specialnich-poradkovych-jednotek-z-cele-republiky/
  25. ^ "I beat pirates with a hose and sonic cannon". BBC News. May 17, 2007. Retrieved May 11, 2010. 
  26. ^ Sonic Device used to repel pirates
  27. ^ David Osler, (2 December 2008). "Sonic solution may not be a sound investment", Lloyd's List. London: Informa. Retrieved 13 April 2011.
  28. ^ http://www.mailonsunday.co.uk/news/article-2396147/Pirate-hunter-How-British-ex-Marine-bodyguard-stars-escaped-death-fighting-feared-hijackers-high-seas--run-secret-network-Somali-spies-London.html
  29. ^ Sloan, Gene (January 17, 2011). "Cruise ship blasted pirates with sonic wave". USA Today. Retrieved July 17, 2011. 
  30. ^ News, BBC (12 May 2012). "'Sonic weapon' deployed in London during Olympics". BBC News. Retrieved 11 May 2012. 
  31. ^ Darby, Andrew (February 6, 2009). "Whalers attack activists at sea". The Age (Melbourne). 
  32. ^ Video - Sea Shepherd
  33. ^ Sea Shepherd Battles Japanese Whalers in the Ross Sea - Sundance Channel, 7 February 2009
  34. ^ "Street Fight on the High Seas". The New Yorker. 2010-01-12. Retrieved 2010-01-16. 
  35. ^ "Ride Of The Valkyries: Japanese Whalers Claim Sea Shepherd Harasses The Nisshin Maru With Classical Music". Underwatertimes.com (Tokyo). February 9, 2010. Retrieved January 1, 2011. 
  36. ^ This Pain-Inducing Acoustic Device Used to Control Crowds in Azerbaijan Might Be U.S.-Made, The Atlantic, March 14, 2013
  37. ^ http://www.lapresse.ca/actualites/montreal/201405/22/01-4768807-la-police-de-montreal-se-dote-de-canons-a-son.php
  38. ^ [=http://www.eldiario.es/politica/Centenares-personas-recorren-Madrid-Gamonal_0_219078935.html El Diario : News : Los mossos utilizan un cañón de sonido para dispersar a los manifestantes en Barcelona]

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