This post describes a field sound recording of a wind turbine, 29-4-2012. There are MANY in Denmark, but only few in the Copenhagen region for some reason. The noise, especially the very deep and far reaching rumbling sound is currently heavily debated. It appears to be a challenge to really get hold of how those wind turbines actually sound and the precise characteristics will always depend on types and sizes of wind turbines. It is a bit complicated.
Using my usual dummy head recording setup, with QTC40’s, pressure equalizers and an extra layer of wind protection, I have tried to make a clean and realistic recording of a wind turbine.
Listen to a short sound sample of the wind turbine noise at low and higher wind speeds – waw 4Mb
This short clip summarizes the wind turbine noise at low and higher wind speeds. Here in uncompressed wav format to preserve the full original quality and full as-recorded low frequency contents.
The recordings were made at a local wind turbine, a relatively new 80 meters high, 850 kW, Vestas V52 turbine. It was an early Sunday morning, 8 am, to minimize the noise from a nearby motorway. It felt kind of windy, estimated 5-6 m/s, but fluctuating. The sound from the wind turbine varied a lot according to the wind speed and the position/distance. Directly underneath it was surprisingly silent. But at a distance of 50 meters in front of the tower there was a spot where the noise appeared most clear and direct, so this was chosen for the recordings.
Download mp3- 11 minutes of vind turbine noise.
The video above is a 10 minutes take. Notice how the fluctuating wind alters the rotation speed and the sound level. In the video and mp3 version, a bass roll off has been applied to reduce the deep rumble and to make the sound more “realistic” in headphones.
Looking more into the technical details, the sound appears to be composed of a very deep rumble, some semi-deep gear sounds, and higher pitch turbulent noises from the fast rotor blades. As the specs of the Earthworks, QTC40’s microphones says +/- 1 dB from 4Hz to 40 kHz, I was hoping to pickup the full audio spectrum from the turbine, maybe even deep infra-sounds. A major challenge here, was the wind which has a habit of generating plenty of similar deep rumbling. To reduce this problem, I was applied a double layer of nylon stocking material as wind protection and often manually shielding the setup with my jacket. I wonder how the official noise measurements are carried out overcoming the task of recording very low frequencies at high wind speeds.
Taking a closer look at the results, the figures up and below give a comparison of the frequency spectrum, when comparing the sequences with lowest and highest wind speed, estimated 4 and 7 m/s. This gives an unscientific indication of the direct contribution from the wind turbine to the overall noise in competition to the motorway and other wind noises. Apparently, increasing the wind speed gives an amplification of about 6-10dB right evenly over the range 10-10000 Hz. The low-frequency content is substantial. Of course, this is would hardly be visible in conventional A-weighted noise estimates.
Speaking about the very low-frequency or subsonic noise, as the word says it can hardly be heard. To be able to reach those frequencies the sample below has been pitched up by a factor of 4. That means 10 Hz transforms to 40 Hz, and 20 Hz -> 80 Hz, etc. Dont know how useful this technique is, but it sure add a strong effect to the recordings…
ORIGINAL high/ low winds – 4 MB wav file
More images from the recording setup:
So, what is your experience with wind turbine noise? Outdoor or indoor. Can you recommend other audio recordings illustrating this? You are welcome use the comment section below.
See professionally made audio recordings of wind turbine noise: http://www.masenv.co.uk/listening_room
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By: Mike on February 10, 2013
at 13:57
[…] Larsen demystifies the sound produced by an operating wind turbine. It was originally posted at his blog Recordings of […]
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By: Demystifying the sound of wind farms | YES! to renewables on April 8, 2013
at 01:53
[…] Learn more about this Wind Turbine sound. […]
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By: Wind Turbine | White Noise Market on April 8, 2013
at 14:47
[…] Up close, you get a feel for the silent majesty of these machines. Usually, we associate size with noise. For instance, a coal truck is incredibly large, and unsurprisingly, incredibly noisy. We expect big things that move to make a lot of noise. Yet, when you stand beneath a wind turbine, watching tons of fibreglass and steel rush overhead, the sound level is astonishingly low. […]
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By: Ten Good Things (about wind energy) | YES! to renewables on April 9, 2013
at 02:30
very good
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By: cftvgvdca@gmail.com on December 3, 2014
at 13:53
[…] To get a good recording of a wind turbine itself, it is important to screen out other sounds (traffic, wind rumbling across microphones, aircraft). See the details. […]
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By: The Sounds of Wind | Hypergeometric on September 17, 2015
at 03:09
[…] more detail about this remarkably high quality sound recording, click on Recordings of nature’s Blog (April 30, […]
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By: Do terrible turbines make Maria mad? « Wednesdays with the decently profane on November 11, 2015
at 13:24
I used to believe there was no basis whatsoever with regard to wind turbines and adverse effects on human health…that is until I learned about barotrauma in bats who flew into the vortices created by the blades. Coincidence? I think not
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By: Linda Loo on October 16, 2017
at 01:28
I would like to put this wind turbine sound on my sound map . Do u have geotag, coordinate gps please? Tx
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By: Thierry Vuillermet on March 17, 2021
at 21:58
The location is 55.661763, 12.283695
https://www.google.com/maps/place/55%C2%B039'42.4%22N+12%C2%B017'01.3%22E/@55.661763,12.2818539,505m/data=!3m2!1e3!4b1!4m6!3m5!1s0x0:0x0!7e2!8m2!3d55.6617633!4d12.2836954
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By: recordingsofnature on March 19, 2021
at 12:31
Thanks a lot. It’s done.😀 You can find your field recording on my sound map here : https://www.ecnelisfly.com/zoomfly_en/1012
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By: Thierry Vuillermet on March 19, 2021
at 17:16
[…] Wind turbine sound – field recording […]
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By: Wind turbine sound – high quality audio | 1energy.info on June 25, 2021
at 06:17