Talk:Long-range acoustic device

message: Perhaps one of the most relevant issues for new weapons technologies called "non-lethal" is that of the potential for injury or lethality; for instance, both rubber/plastic bullets and Tasers are described by their users as "non-lethal," but both have caused multiple deaths. A serious discussion of the potential for injury or permanent hearing loss would be very helpful here, especially as the LRAD is being deployed against U.S. citizens by U.S. government entities. I hope some one who cares about this issue can address this?  — Preceding unsigned comment added by 75.132.12.83 (talk) 18:18, 8 August 2013 (UTC)
replies: text: I created a "Risks" sub section a few days ago, with information about hearing damage and pain caused by the LRAD. A few lines in this section were changed, omitting the info about hearing risks and contradicting the sources that are being cited in those lines. Also, one of the new edits says that "the LRAD is often incorrectly called a sonic weapon," while my edit said that it is "is often considered to be a sonic weapon." The controversy of whether or not the LRAD is a weapon should be better explained in this section of the article, so that both sides of the issue are presented. --ChromePlated (talk) 00:37, 10 June 2020 (UTC)
replies: text:  Update: another user has reverted this change. --ChromePlated (talk) 03:22, 10 June 2020 (UTC)
thread_title:  Request for Section on Potential for Injury or Permanent Hearing Loss 

message: Can anyone confirm that this is an LRAD being used at a protest in Will County IL?
http://www.youtube.com/watch?v=6WkcvFc-78w&feature=autoplay&list=UU3hkeAXkYAPiL-9qqlhmlmQ&playnext=3
While this is not certain, looking at the LRAD Corporation website, it appears to be an LRAD 500X-RE (http://www.lradx.com/site/content/view/2054/110/).  — Preceding unsigned comment added by 73.36.162.56 (talk) 19:43, 10 April 2015 (UTC)
replies: text: Yes, LRAD can be used for projecting an announcement. Since this talk page is only used for discussion about how to improve this article, I would say that we shouldn't use this video as a reference because it is not a reliable source and if anything will be an original research. Z22 (talk) 02:43, 11 April 2015 (UTC)
thread_title:  Is this an LRAD? 

message: Article says, "American companies have been banned from selling arms to China since the 1989 Tiananmen Square Massacre, but the LRAD is described by ATC as a “directed-sounds communications system".[7]'
-- Perhaps there used to be a description of ATC in previous versions, but in any case it's currently an abbreviation without an explanation and the link it leads to, #7, is a dead link.
What is ATC? tharsaile (talk) 17:24, 21 March 2011 (UTC)
thread_title:  What is ATC? 

message: WHO keeps changing the USAGE page regarding Paul Watson and the SSCS? It was the Japanese that used the LRAD in self-defense the why it is worded now makes it look like they were secretly used to attack the activists
The LRAD uses a phased array which via constructive and destructive interference causes the sound to be more directionalized.  It is not just a big speaker as the article suggests.  Look at a description on How Stuff Works dot com.
: Actually, read reference #1.  Phased array or not, any loudspeaker with the same diameter will have exactly the same (if not more) directivity as this device.  Beranek is a much better reference than howstuffworks.
----
I have seen a video about one of these devices
it is designed to only project in a 90 degree or 180 degree
one of these could be taken out by a sniper our somone with a shotgun
Dudtz 9/24/05 12:46 PM EST
Made the distances consistent, if they are wrong please change them, but a yard is roughly a metre. There are three feet to both a yard and a metre. (Notice: metre, not meter, tee hee hee). 134.226.1.136 15:38, 6 November 2005 (UTC)
replies: text: Hmmm. I'm still no happy with it, with conversions removed it reads: .....33 inches in diameter. At maximum volume, it can emit a warning tone that is 151 decibels at 1 metre..... It just seems wrong to have inches in one sentance and metres in another. And I'm really not sure what a Watt per metre means (decibel conversion). -- Zaf 04:21, 9 November 2005 (UTC)
thread_title: Description is Inaccurate

message: "At maximum volume, it can emit a warning tone that is 151 dBSPL (1000 W/m²) at 1 metre, a level that is very capable of permanently damaging hearing, and 50 times the normal human threshold for pain."
What threshold of pain figure is being used to arrive at this factor of 50? -- 70.81.118.123 06:07, 28 April 2006 (UTC)
replies: text: Hmm, actually, that should be 150 dBSPL, which I just fixed. Anyway, the threshold of pain is described as being around 120 to 140 dB. Since the threshold of hearing is I0 = 10-12 watts/m2, and IDB = 10 log10( I / I0), the exact figure that would make 150 dB fifty times the threshold of pain would be 133.0 dB. — TheKMantalk 09:46, 28 April 2006 (UTC)

text: Well, I added a link to the Absolute threshold of hearing article, which shows a range for threshold of pain. I think I'll stick in a number as well. Thanks — TheKMantalk 14:00, 30 April 2006 (UTC)

text: 133 dB (-6dB per doubling distance) assumes equal dissipation in all directions so calculation is already wrong simply from LRAD being a beam. 89.36.65.39 (talk) 21:01, 11 June 2020 (UTC)
replies: text: Sound doesn't work that way. Any dispersion pattern other than a coherent beam (laser) disperses at -6dB per doubling of distance along any given axis in the far field. Despite the hype this is not a laser. Greglocock (talk) 23:54, 11 June 2020 (UTC)
thread_title:  Threshold of pain 

message: Quote: "...can emit sound in a 15 to 30° beam (only at high frequency)..."
:Does that mean the LRAD is only capable of a 'beam' that focused when projecting high-frequency sound, or that it is totally incapable of projecting low-frequency sound? -Toptomcat 15:58, 30 October 2006 (UTC)
thread_title: Focus and frequency

message: The paragraph which mentions a regular loudspeaker and the wave number is extremely confusing. If this is true, what's the difference between LRAD and a big speaker? What does wave number have to do with it? I'm of the opinion this should be removed or cleaned up to make sense and to fit well with the article. anonymous6494 22:25, 3 February 2007 (UTC)
thread_title:  Remove? 

message: I do not mean to be insulting to the idea of a Long-Range Acoustic Device with the comparison, but at least on video it is indistinguishable from a standard car alarm. I understand that it is more directed and louder in relation to distance, but the philosophy seems to be identical. Since car alarms are proven not to embarrass thieves or attract the attention of passers-by, due to their sound being so common, alarm manufacturers seem to be using the same strategy as Long Range Acoustical Devices: making the alarms so loud as to keep the thief from being able to think straight enough to steal the car. Is it inappropriate to include a paragraph in this article? --Zachbe (talk) 07:09, 30 September 2009 (UTC)
replies: text: No, the car alarm link is not useful at the bottom or in the middle of the article. Connecting car alarm with LRAD without an expert source is synthesis. If an expert compares them, put it in the article. Binksternet (talk) 12:09, 14 October 2009 (UTC)
thread_title:  car alarm comparison paragraph? 

message: :The device does not use ultrasound, nor is it a phased array; it uses an array of conventional acoustic tweeters
Entirely incorrect I think. It is my understanding that the tweeters, acting in phase and thereby addding to each others' magnitude, are a phased array? This is what causes the volume to drop dramatically outside the cone of influence - the tweeters on the outside are of the opposite phase, and therefore cancel out the tweeters on the inside...  —Preceding unsigned comment added by 99.228.57.131 (talk) 08:51, 28 August 2010 (UTC)
thread_title:  Not a phased array? 

message: I saw this device on TV a while ago, according to what they said, it is made of a bunch of very tiny ultrasound speakers that emit sound in the ultrasound range modulating it to produce audible sound, it uses ultrasound because the higher frequency disperses significantly less than frequencies in the audible range. What gives? --TiagoTiago (talk) 02:02, 11 December 2010 (UTC)
thread_title:  Not ultrasonic? 

message: http://images.businessweek.com/slideshows/20111222/occupiers-and-evicters/slides/13 Evict: New York police say they used Long Range Acoustic Devices, which blast up to 110 decibels of sound, as megaphones and not as “horrible noisemakers”
99.190.86.5 (talk) 07:48, 28 December 2011 (UTC)
thread_title:  [[Occupy Wall Street]] resource, [[Businessweek.com]] 

message: While I don't have authoritative sources that are worthy of being cited in a Wiki article, there exist several informal accounts from word of mouth, and a few on message boards/forums, indicating that simple $2 or less earplugs render LRADs completely ineffective.  I'm sure anyone who purchases one of these things or tests it would test it on a subject wearing earplugs versus no earplugs, but have there been any credible and authoritative publications on this matter?
173.3.109.197 (talk) 18:14, 10 August 2013 (UTC)
replies: text: Would doubt that. This video tests some countermeasures. Best countermeasure seems to be rough paper. Which brings me to my next part. Should we maybe add a section on countermeasures? (Is it ok I edited the section title btw? --2003:CC:3706:C388:D115:A483:4E33:8AD6 (talk) 14:38, 7 June 2020 (UTC)
replies: text: I'd be cautious on that. Ben's a great guy, and his video is informative, but its not wikipedia grade authorative. At the end of the day LRADs are just sounds, and all the principles that apply to sound apply here. a 2.2K frequency is about 2cm wavelength. (There are apps on the net that would likely to give an accurate number, this is just off my head) The higher end ones 15k would clock in around 1 or 2 mm. Knowing in advance what the frequencies are would let someone construct a sound shield that could block it quite effectively. But as original research that would be outside wikipedias scope. Perhaps there are academic papers on the topic? Duckmonster (talk) 09:57, 24 November 2021 (UTC)
thread_title:  Countermeasures/Ineffective Against Simple Ear Plugs 

message: Hello fellow Wikipedians,
I have just modified one external link on Long Range Acoustic Device. Please take a moment to review my edit. If you have any questions, or need the bot to ignore the links, or the page altogether, please visit this simple FaQ for additional information. I made the following changes:
*Added archive https://web.archive.org/web/20100103231027/http://www.seashepherd.org/matilda/video.html to http://www.seashepherd.org/matilda/video.html
When you have finished reviewing my changes, you may follow the instructions on the template below to fix any issues with the URLs.
Cheers.—InternetArchiveBot (Report bug) 04:00, 14 December 2017 (UTC)
thread_title:  External links modified 

message: The section about Australia, previously removed because the only source was the this article from the Epoch Times which is not a reliable source, has been replaced this time with a reference to an article on World Nation News.  The problem is the World Nation News article is an exact duplicate of the Epoch times article by the same author.  That author's email address is within the Epoch Times web domain so I am confident that the Epoch Times is the original article.  Consequently I am going to remove the Australia section from this article again as failing verification. - Nick Thorne talk 08:38, 20 February 2022 (UTC)
replies: text: Agree, . Just about to re-create a section with reliable sources and information. Laterthanyouthink (talk) 07:13, 22 February 2022 (UTC)
thread_title:  Australia section 

message: No expert on the techology here, but a quick glance tells me that most of the uses in the Deployments and uses section seem to be for crowd/protest control, and then the following two sections are basically by function... Wondering if the major subheadings should be by function and then (if necessary), sub-subheadings by country? Just a thought. Laterthanyouthink (talk) 08:35, 22 February 2022 (UTC)
thread_title: Rearrangement of sections?

message: I've suggested a merge from Acoustic hailing device, an almost completely uncited article, into this one. It seems to contain almost identical information. I'm not 100% sure about the naming, or whether the Genasys product is the only one on the market, but LRAD appears to be the common name these days. Laterthanyouthink (talk) 04:14, 23 February 2022 (UTC)
replies: text: Klbrain (talk) 11:19, 30 December 2022 (UTC)
thread_title: Merge proposal

message: Risks section is misquoting OSHA - OSHA indicates that you need hearing protection for 90db or higher for 8 hours a day. To explain how loud 90db is, think of a lawnmower.
Sounds greater than 150db are harmful for any amount of time. It is my understanding that these devices usually do not go over this level as measured at 1 meter. Sounds less than 150db are usually not considered dangerous if they last less than 1 second.
I think it is also worthwhile to bring into this discussion distance as well. Operators of these devices are usually required to use hearing protection even though these devices are directional due to the high volume levels. For somebody in the directional path of a system measuring 150db at 1 meter, it would be 114db at 64 meters (about 210 feet) which is safe under 15 minutes without hearing protection according to OSHA. Not trying to make the argument that a LRAD cannot hurt somebody just trying to get a revision here because the original statement is missing context and if we add the context we might as well add the mitigation methods. 206.251.42.246 (talk) 06:26, 24 June 2023 (UTC)
thread_title:  Revise Risk section