Thursday 24 September 2015

Is it sounding like noise?

"The difference between sound and noise, is that noise is unwanted."

There is much in the media at the moment about wind farms. In particular about their viability as an alternative energy source. The government is concerned about the  “Noise” they make. There is an excellent paper outlining all that relates to wind farms, "noise" and their development for anyone who wishes to know more."The noise emissions associated with Wind Farming in Australia".

Windfarms create high levels of infrasound and low level frequency noise. 

They say you can have a normal conversation standing underneath a wind turbine. 
Those who oppose the wind turbines say that these infrasonic frequencies might release endorphins that won't let people relax: it might interfere with our brain waves. There is much that we don't know yet about sound and all of its properties. What we do know is that coal can be hazardous for many reasons. It was certainly a respiratory hazard, with other adverse health effects, acknowledged by  the Royal Commission into the Hazelwood Open Cut Mine Fire in 2014.  


Sound can be classified into different frequencies. The frequency is the speed at which it vibrates per second: Interestingly, Hertz is the German word for Heart. I remember at University delighting in the coincidence: the possibility that something at a higher frequencies might have a higher “Heart"
Just so you know...
Infrasonic: below 20z
Ultrasonic: above 20000 Hz
Supersonic: (faster than the speed of light). 

Where I am living in the urban bush (the middle of a State Park) presently, there are 3 sonic mice repellants plugged into wall sockets. Apparently, they are working well here, as before there were lots of mice in the house. I haven’t seen any, nor heard any (which is nice!). It seems like the dawn of a new implementation of technology, with sound being used to repel many animals. Using a phone app can exude the correct infrasonic frequency to repel mosquitoes. The mosquito frequency sits between 9.6 and 18.2 Hz depending upon the many factors that affect when mosquitoes come out to eat. Mice frequency sits higher at 32-62 Hz. And, just for some extra knowledge those dog and cat whistles are ultrasonic, being at 20000-25000Hz, out of our human hearing range. Check out our human Ranges of Hearing.

Just because we can’t hear something as humans, doesn’t mean it is not “hearable” (audible) It still means that it exists and we may just need the correct instruments to measure the sonic patterns. It can still affect us, possibly in both positive and negative ways. Here is a great story of a hearing impaired man who is recording the wifi landscape.  Wifi also has an infrasonic frequency and it is growing rapidly around us. Most homes these days in our modern, urban world are connected to Wifi and yet no one says their Wifi is noisy. (They may and do voice concerns about it in our environment).

We have found and are still finding all sorts of uses for these sound frequencies. 

As I sit here writing this, I have the crackle of the open fire, birds singing in the late pre-spring sun and the constancy of the Yarra River that never seems to stop making sound. I have been wondering whether the river is classified as white "noise", or pink "noise". As the river is near the rapids, apparently, it is more like red noise. It is loud and constant and took me a long while to get used to it.  I wrote a poem about the sleepless nights, called RiverBed.

All these colours remind me that there are rainbows of colour in light and that through the light we can see the colour. Messiaen was certainly a composer who used particular scales as they represented particular colours, and it is the Synesthete who often will say they see colours when they hear music. How exactly are light and sound related, and how do we explore this in more depth? I am indeed curious. 

The many different coloured noises are also amazing. Pink noise is white noise, with a predominance of lower frequencies so it sounds deeper.Pink noise affects tides and river heights, our heart beat, and the firings of single neurons. Pink noise can be found in pitch and loudness variations in speech and music.

White noise has been used as a remedy for tinnitus (ringing in the ears) and some people turn their radios to off the dial to get this white noise, and there are a multitude of you tube videos as well as sleep CD's to assist those who hear the constant zing. 

There is a voice and speech exercise that focuses on garnering the breath to sustain fricative sounds. The first is ssssss, which is “white noise” The second is shshshsh, which is pink noise.

Interestingly, a study in one of the big four banks here in Australia revealed that with piping pink noise through their speakers, there were less reported complaints. So perhaps pink noise is a key in achieving harmony…So much yet to discover about these frequencies. 

Back to wind farms....Engineers are looking to Owls for creating  the best blade design for wind farms, as Owls are renowned for hunting and flying soundlessly and they are keen to make blades that emit the smallest amount of "noise". We are on the cusp of this new advancing technology. 


What are your thoughts?

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