NASkeet Samba Member
Joined: April 29, 2006 Posts: 2947 Location: South Benfleet, Essex, UK
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Posted: Fri Aug 29, 2014 8:18 am Post subject: 1970VW Type 2: Investigation of elephants’ sub-20Hz hearing |
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Members who have been watching the recent series of three television wildlife documentary programmes on BBC 2, entitled “Super Senses: The Secret Power of Animals”, might have noticed in Part 2, the South African specification, 1970 VW Type 2 Westfalia campervan (registration No. CL 44875), temporarily fitted with an unusual type of large infrasonic-sound speaker (i.e. Eminent Technology's TRW-17 Rotary Woofer), to test the hearing and behavioural response of African elephants, to the infrasonic sounds from a recorded thunder storm.
http://www.bbc.co.uk/mediacentre/proginfo/2014/33/super-senses-sight
Patrick Aryee & Helen Czerski, “Super Senses: The Secret Power of Animals – Part 2 of 3”, BBC 2, Tuesday, 26th August 2014, 9:00 pm & Wednesday, 27th August 2014, 10:20 pm.
http://www.bbc.co.uk/iplayer/episode/p024g1nl/super-senses-the-secret-power-of-animals-2-sound
John Crace, “Super Senses: The Secret Powers of Animals – review: the elephants were gems, but the star was the golden mole”, The Guardian, Wednesday, 27th August 2014.
http://www.bbc.co.uk/programmes/articles/5Qfy0G5hrsFMXLBGJsjmfHQ/sound
http://www.theguardian.com/tv-and-radio/2014/aug/27/super-senses-the-secret-powers-of-animals-review
http://www.bbc.co.uk/programmes/b04fhp70
http://www.bbc.co.uk/mediacentre/proginfo/2014/33/super-senses-sight
Bruce Thigpen (Eminent Technology) , “How to build a giant speaker from a camper van”
http://www.bbc.co.uk/programmes/articles/1s7DPYTLm...camper-van
« In January 2014 myself and my colleague Eric Flament travelled to Nelspruit, South Africa to meet with a BBC film crew. They were interested to find out whether elephants would react to very low frequency (infrasonic) sounds from a distant thunderstorm. »
« Our challenge was to make a thunderstorm sound track and design a special low frequency loudspeaker capable of generating the sound of a thunderstorm (lightning and thunder below 20Hz). »
« Creating the sound track was relatively straightforward. We removed the high frequency content from a good quality thunderstorm recording as if the sound had travelled long distances through the air so that we only reproduced infrasound. »
« Creating a sound source was a little more difficult. For the special speaker that can broadcast infrasound (sounds below 20Hz) we wanted a giant speaker box, around 10.2 cubic meters (360 cubic feet). »
« Sam Hodgson, the director, suggested using a VW Bus as the speaker box. The VW Bus is known as a Kombi in South Africa – and has the correct internal volume needed to produce very low frequency sounds. The BBC contacted a supplier of classic Kombi's and decided to use "Jackson" a 1970 Westfallia camper. »
http://classickombis.co.za/k92-vw-westfalia-kombi-camper-1970-jackson
« We found the same type of Kombi locally and using it for a template, designed an insert or speaker baffle for the rear hatch back door that supported a TRW-17 rotary woofer speaker which allowed easy installation and removal for transport. »
http://www.cnet.com/uk/news/worlds-most-amazing-subwoofer-has-no-woofer/
« The pressure from the low frequency sound inside the Kombi caused the roof to flex so we strapped the roof and taped the windows. The sound tests were good, Jackson made an excellent portable infrasound source and we were ready to see how the elephants would react. »
« When the speaker broadcast the infrasonic parts of the storm, the elephants immediately stopped feeding and rotated around to look in the direction of the van. It was an amazing reaction and demonstration of elephant’s ability to hear infrasound and determine the source location with good precision. »
« While we did not directly prove that elephants can detect a rainstorm at long distances we did prove that elephants can hear infrasound at the same sound levels and even with very long low frequency wavelengths. Surprisingly they can determine the direction of infrasound source with excellent accuracy. » _________________ Regards.
Nigel A. Skeet
Independent tutor (semi-retired) of mathematics, physics, technology & engineering for secondary, tertiary, further & higher education.
Much modified, RHD 1973 VW "1600" Type 2 Westfalia Continental campervan, with the World's only decent, cross-over-arm, SWF pantograph rear-window wiper
Onetime member, plus former Technical Editor & Editor of Transporter Talk magazine
Volkswagen Type 2 Owners' Club (Great Britain)
http://www.vwt2oc.net
Last edited by NASkeet on Fri Aug 29, 2014 8:44 am; edited 2 times in total |
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suffecool2 Samba Member
Joined: May 15, 2011 Posts: 355 Location: chambersburg, pa
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Posted: Fri Aug 29, 2014 8:29 am Post subject: Re: 1970VW Type 2: Investigation of elephants’ sub-20Hz hear |
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NASkeet wrote: |
Members who have been watching the recent series of three television wildlife documentary programmes on BBC 2, entitled “Super Senses: The Secret Power of Animals”, might have noticed in Part 2, the South African specification, 1970 VW Type 2 Westfalia campervan (registration No. CL 44875), temporarily fitted with an unusual type of large infrasonic-sound speaker (i.e. Eminent Technology's TRW-17 Rotary Woofer), to test the hearing and behavioural response of African elephants, to the infrasonic sounds from a recorded thunder storm.
Patrick Aryee & Helen Czerski, “Super Senses: The Secret Power of Animals – Part 2 of 3”, BBC 2, Tuesday, 26th August 2014, 9:00 pm & Wednesday, 27th August 2014, 10:20 pm.
http://www.bbc.co.uk/iplayer/episode/p024g1nl/super-senses-the-secret-power-of-animals-2-sound
http://www.bbc.co.uk/programmes/b04fhp70
http://www.bbc.co.uk/programmes/articles/1s7DPYTLm...camper-van |
The article is very interesting, but I'm not able to view the video here in the U.S. _________________ '71 Hightop - rolling resto/customization in process
'87 Golf - tranny's toast, but still runs
'70 bone stock Westy - gone |
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