Sounds from Hong Kong

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Summer Trip 2011- Part 2

Hong Kong is a place of stunning water and islands, where the old and new coexist. The skyscrapers, a veritable crowd of high-rise giants lean together with their toes at the waters edge. Sounds ricochet out between them, like an amplifier, especially when the fireworks show is happening. Here are snap shots and sound bites from the second part of our three-part trip to Asia.

Veiw from Hong Kong Island to the main land

[audio:https://shirleypegna.com/wp-content/uploads/2012/01/HK-shopping-bounce1.mp3|titles=Street level hubub ]

I was interested to find an interview with Yang Yeung, a Sound Artist, resident of Hong Kong and director ‘Sound Pocket’, describing the way sounds are perceived from high up the buildings, ‘I remember going up to a 20-storey factory building with some friends in Aberdeen, south of Hong Kong Island. It used to be a fishing village and now a vantage point for getting boats to outlying islands. We stood on the rooftop one sunset and the birds were playing around. The traffic noise from below was audible, but not disturbing. It’s like it is suspended on the 18th floor or something, forming a “cloud,” hanging.’
http://www.examiner.com/experimental-arts-in-national/susie-law-wai-shan-yang-yeung-soundpocket-and-hong-kong-s-soundscapes

View from my brothers' flat - 30 stories up!!

30 stories up, the ground seemed like another world away, and quite quiet. The sky seems to move and the buildings actually do sway about especially in a high wind and especially typhoons that are quite common. My brother, who lives with his family in Hong Kong, described the improvements done to the design of the foundations of the high buildings so that the surplus rain does not damage their stability. Even now, during the typhoon storms , the movement from the tower blocks’ is quite dramatic, especially the higher up you are. To warn you of an impending typhoon, and especially the boats in the harbour, a signal is sent out. Historically it would have been a gun or explosive so ships would and still do take cover by the shore, although now it is broadcast over TV and radio.

Commenting on sounds representing Hong Kong nowadays, Yang Yeung says in an interview with Pandie Ho ‘I wouldn’t say it is representative, but the “doot” of Octopus cards dominates the everyday soundscape. But I miss the sounds of the coins going through the slots on public vehicles.
http://hk.asia-city.com/events/article/upclose-yeung-yang

I didn’t get a recording of the Octopus cards, (equivalent of our Oyster card) but did get the omnipresent pedestrian crossing beeps.

[audio:https://shirleypegna.com/wp-content/uploads/2012/01/HK-beeps-bounce.mp3|titles=pedestrian crossing]

Ignoring the beeps - on neighbouring Lan Tau Island

In a side street – Qingming or Ancestors day – observed here by office workers in their lunch hour by burning money to be carried in the smoke, up to their ancestors.

Ancestors Day

[audio:https://shirleypegna.com/wp-content/uploads/2012/01/day-of-dead-bounce.mp3|titles=Qingming ceramonial music]

Aficionados for the Qingming ceremonies

Still working daily down on the water, the Star Ferry takes passengers from the main land Kowloon, to Hong Kong Island for a mere couple of Hong Kong dollars. The Star Ferry Company, dating back to 1888, still has its 1933 diesel electric engines. The top deck is still the first class and the bottom second class, and climbing on especially the lower deck you hear the lovely diesel engine and smell of oily fumes, and the vibration goes through your bones.

Weighty rusty anchors on the Star Ferry

[audio:https://shirleypegna.com/wp-content/uploads/2012/01/HK-ferry-bounce.mp3|titles=below decks -Star Ferry]

Start Ferry - late night crossing

Sounds from Seoul

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Summer Trip 2011 – Part 1

Asia was noisy and busy and amazing! Here are the sounds from the first part of our three-part journey this summer. Listening again to my collection of sound snapshots of the places has reminded me how even a short sound bite can put you spatially, geographically and sensationally right back to where you first heard it. We touched down first in Incheon International Airport -South Korea. We took the metro from the airport to the city.

View out of the train window on to wild terrain on the way into town

With the archaic landscape outside, the inside was a contrastingly ultra modern experience with air conditioned sped along with alternating western style trumpet fanfares and traditional music motifs as the doors opened. Voices announced directions in multiple languages while screens kept you amused – if at the time you weren’t taking advantage of the all-available Internet!

[audio:https://shirleypegna.com/wp-content/uploads/2012/01/blog-metro-soeul-bounce-23.mp3|titles=blog metro soeul bounce 2]

View inside the train

In the city there are stark contrasts with old and new culture. Young people form all over Asian look to Seoul for their contemporary culture. These two BBoys (pictured) were telling me how the Koreans are leading the International field in dance where BBoying is concerned.

Above ground in the centre of the city at Gyeongbokgung Palace, is evidence of an older culture, and the traffic sound coexisted strangely with the conch shell bugles and shell rattles of the changing of the guard. (And my recorder battery ran out at this point!)

The changing of the guard at Gyeonbokgung Palace

Away from the centre however, the extraordinarily loud noise of the cicadas could be heard in the city streets.

[audio:https://shirleypegna.com/wp-content/uploads/2012/01/seoul-cicadas-bounce1.mp3|titles=seoul cicadas bounce]

Seoul city streets

Here’s the street where we heard, the equivalent of the rag and bone man drive up and down in the rain in his battered truck calling on his mega phone for unwanted electrical goods.

[audio:https://shirleypegna.com/wp-content/uploads/2012/01/seoul-trader-bounce-21.mp3|titles=seoul trader bounce 2]

The presence of the rain (there was unusual city wide flooding as we visited Seoul), the heat and the solid rock of the mountains gave me a feeling for the ‘elemental substance’ of the place. At the Asian Art Museum, the beautifully restored house of a highly renowned teacher of the ideas of Confucius, we were shown and played the traditional instruments, gongs, cymbals and drums, that represented the elements: thunder, lightning, dancing, rain, sun and wind.

[audio:https://shirleypegna.com/wp-content/uploads/2012/01/wind-gong-seoul-bounce1.mp3|titles=wind gong seoul bounce]

The calm 'kitchen courtyard' of the Asian art Museum

At the other side of town by the port were the familiar thrills and spills of the fairground.

Fairground near the port

[audio:https://shirleypegna.com/wp-content/uploads/2012/01/fairgr-seoul-bounce1.mp3|titles=fairgr seoul bounce]

Koreans felt to me to have toughness in their genes judging by their history, ability to survive, their fitness and their inventiveness. It’s a popular national pastime to walk in the National Parks, so we joined in, took the metro and explored the nearest of the parks, Bukhansan National Park, climbing 739 metres to a peak over looking the city.

At the top of the mountain with a couple of cool cats

On the way down, with light fading, we came across a temple built over a spring and heard as we descended the temple bell through the trees

[audio:https://shirleypegna.com/wp-content/uploads/2012/01/temple-gong-bounce1.mp3|titles=temple gong bounce]

The Cheonchuksa Temple

Getting The Vibes

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Back in the summer I went to visit a friend who kindly said she would come and experience the sound from the ground, from a mic in the ground playing through a sub woofer in my car, and let me write down what she thought about it. Gemma’s experience was going to be different from mine as she is profoundly deaf.

 

Gemma and Willow

We put a geophone (microphone) 30 meters from the car into the grass in the park and sat in the car and watched the people go by. We felt the vibrations of their feet, and the vibrations of the traffic from the road being picked up by the mic and playing through the subwoofer (speaker).

There was road works about 150m away so after a while we went on to another park away from the main road, and that was quite busy with people walking, children playing, bird song and dogs barking. I attempted to record Gemma’s reactions to the subwoofer’s vibrations, and ask questions that would help me imagine what is was like to experience the world without sound, but visually and through the experience of vibration.

Connecting to the mic in the ground

Shirley. In the ground there is sound \vibration from the city: a low din going on. So even without drills and traffic, there’s quite a lot of noise. What is your reaction to this sound?

Gemma. It’s surprising what noise is there to be amplified – but it’s not obvious here.

S. Have you heard/felt vibrations like these (from the sub) before?

G. Yes.

S. Do you know where the sounds/vibrations are coming from?

G. If I see visually then yes – other wise no.

S. Do you notice, or are you ever aware of vibrations when you don’t know where they are coming from, and is that usual?

G Yes – If  I’m around hearing people, I ask what that noise is!! Usually I have to describe what I’m feeling to match what it sounds like.

15″ sub in the car

S. When some one asks me to ‘listen!’ I am aware of lots of sounds I don’t usually tune into. Is this the case with vibration?

G Yes. But only if it’s loud enough for me to feel!!

S. Is there a whole series or gradation of vibration you can identify?

G  There are some vibrations I do recognise if I don’t see it – e.g. a ball bouncing on the floor and something being dropped or a glass smashing on the floor.

S. Is it  (the vibration from the subwoofer) different if I close the car door?

G.  A bit.

S. When the drill isn’t drilling, can you feel the traffic rumble from the road?

G. Yes a bit –

S. How do you feel the vibrations? For example – in your bones or through your skin?

G. In my diaphragm and through my feet.

S. Wow – How did you come to realise this was happening? When you were younger did you remember becoming conscious of it?

G Well, I never really had any hearing after the age of 12, so from the age of 12 I became more conscious of vibrations and since then I’ve made lots of effort to learn and recognise more vibrations.

S. Are you influenced by different vibrations?

G. Irregular vibrations are irritating – man made – gets annoying. Regular rhythms are better nicer.

S. Do you think other deaf and partially hearing people you know feel the some as you?

G Well, I know my family is the same as me, and some deaf people too. I think most deaf people and partially hearing people have some sort of hearing therefore they are more oblivious to vibrations.

S. Do you ever talk about the quality of the ‘vibes’ to other deaf and partially hearing friends?

G Yes – If I’ve seen a band or at a gig that I really enjoyed the vibes from, I try to spread the word!!

S. Do you have a preference to big or small vibrations? Will you get as close as you can to a speaker at a festival – for the excessive experience – or is it uncomfortable – or are you happy to just have a small amount of the vibe?

G Well.. That depends!! Most of the time I do try to be right next to the speaker, but there has been a few places where it’s really overwhelmingly LOUD and it does get too much for me!

S. Do you know musicians or DJs who are deaf?

G Yes! There are a few – Mostly in London.

 

S. Have you ever come across the percussionist Evelyn Glennie? Yes

As a deaf percussionist, she is very interested in the way we ‘listen’ through our bodies. She became deaf at 8 years old, can hear a bit and lip reads well.   http://www.youtube.com/watch?v=YLvkoAZYAkI

http://culture.uoregon.edu/event/1443

She describes hearing as a form of touch. Would you say touch is a form of hearing?

G Yes, Everything speaks volumes through touch and vibrations. E.g. Visually a guitar does not make any sound to me but when I touch it while it’s playing – it’s amazing!! So many vibrations and rhythms etc…

 

S. Do you go dancing and dance to the vibration of the beat in the music?

G. Yes- like a lot.

S. What are the best beats to dance to?

G. House, reggae, pop – Not complicated Latin rhythms though.

S. Is there anything you can add about the experience of vibration and how it is helpful or pleasurable?

G. Makes me feel heavy.  Sometimes I go through a whole host of vibrations every day, and when it gets too much I do want some peace and quiet!! Bit like you having a particularly loud day?? I can feel the bumpy road but the smooth road is quiet.


S. Can you hear or sense that bird? (Black bird singing very loudly close by).

G. No not at all.

S. Do you match up the visuals you are seeing and the vibration you are feeling?

G. Yes it happens all the time. It’s important and alerts me to danger.

S. I wonder how this differs from a hearing person? We all use our hearing to alert us to danger – from crossing the road listening for traffic, to keeping safe from dangerous people like muggers and burglars!! How much do partially and profoundly deaf people depend on vibration for personal safety?

G We don’t – We rely on our eyes for alerts to danger. Vibrations are difficult to judge for danger.

S. Do you feel your own hart beating/vibrating?

G. Yes but I’m used to it. It is alarming when it’s racing and I’m out of breath.

S. What other vibrations alarm you?

G I can’t think of anything – one might be someone running towards me as it gets louder with each step and when I recognise the vibration I do look around to make sure I’m safe.


S. Are there any other internal vibrations from your body that you are aware of? My bones click sometimes. Can you feel that? When you have a thumping head ache, are you sensitive to small vibrations?

Yes! And Yes… I like to stay in bed when I’m hung-over or ill,  as I know it’s very very quiet there!!!

S. Can you feel high sounds at all, and if so what are they?

Not really – Maybe a glass smashing as I know that’s high, but not much.

 

S. There’s a sound artist\musician, Kaffe Mathews, who has made a sound piece that’s bed you lay on that vibrates – sounds saucy!  People lie on it and hear the sounds but also become aware of the vibrations. Ooh!! I wanna try that!!

http://www.musicforbodies.net/wiki/SonicBedMarfa

http://www.musicforbodies.net/w/images/9/90/SBMar_Bodiesw.jpg

‘Ever felt music through your back? Or slide up and down your legs as it spins round your arms to your fingertips? A Sonic Bed will let you do just that .’ kaffemathews.net

 

G. I am enjoying thinking where I feel vibration. No one talks about this usually.

S. What else would you like to explore or point out in regard to vibration?

G Personally, there’s so much more music I’ve not listened/felt yet, and it’s limiting when I need a bass box! It’d be amazing if someone invented speaker gloves that I can attach to an I-Pod and listen to music when I’m out and about!!!

I haven’t been dancing for ages. It’s a great freedom.

 

S. Can you hear of feel your dog Willow?

G. I can’t feel my dog bark, but I can closer up- about a meter away I can.  Growling- only if I am touching him can I feel that. I mostly use visual body language to understand my dog – and the others I look after.

G. It would be good if you, and the car subwoofer system, came to the festival with us (deaf group of friends) and we could dance to the bands without having to go up front right next to the speakers – and I could have my dog with me.

 

S. When we came to the quieter park, I remember you described the small vibration being like the ‘wind’ or the ‘rain’. Inuit have hundreds of words for snow. Have you any other descriptive words for vibrations?  Maybe describing strong vibrations…

G.  Yes – we describe it easily through sign language and make the vibration visual to help describe it to other deaf and partially hearing people. It’s hard todescribe it in English!!

S. Well thank you- for this fascinating insite into the world of vibration! I am now thinking of more and different questions as I begin to put myself in your place.

 

G. Thanks to Shirley for an amazing experience of amplified everyday sounds! It helps me to understand more about hearing people and what they listen to and experience the differences in sounds!!

Seen this car? – Ground Sound!

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You would have seen it at:

Audiograft (audiograft.com) Oxford 16-20/2/2011

People came in the day and the dark and sampled the live subterranean sound.

Ground Sound is an out side sound installation, where listeners can sit inside a car and hear the live sounds of the ground on the car’s sound system. A geophone, planted in the ground, plays through a sub woofer in the boot of the car relaying the low frequencies of the city sound and traffic giving the listeners a different take on the terrain below their feet.

My initial thoughts linked low frequency sound of the car culture – sub woofers playing hip hop beats – with the low frequency and vibration I had been finding with under ground sound. So I made a car sound system that played live ground sounds to see what would happen.

The sound in the car (Ground Sound) provoked dire opposing reactions turning out to be a place of associations and evoking strong physical memories:

Spooky – Scary

Made me feel ill

Lovely low pitch

Sinister and strangely relaxing at the same time

Intense – don’t really know what’s going on

Brilliant – Noisy isn’t it

Love that sound

Very comforting

Ominous and spooky

Not quite comfortable

Kinda novel – Weird

Don’t know what it is but I like it

People had associations from past experiences of sitting in a car, ferry boat or

Watching a film:

Like boat engines in the dock or the rumble of something coming over the hill

Like under water – but nice- all dull muted and a bit fuzzy

Like being a child again – car trip with your parents – being on the back seat

Like you are traveling but you’re not – you notice everybody

Allows you to go away in your head

Like it – bringing the outside in

In this bubble- feels like you’re on a stake out

Feel like I am watching a film playing out

It paces time differently

I can see the ground as if it had surface tension and on top of which we – the pedestrians and the traffic skated like water boatmen –lightly sounding the meniscus or skin on the top of the pond. ( Words form journal 2010)

Surface tension: In Bristol by College Green the sound and vision of the walkers as well as the traffic, and the manifestation of their footsteps hear from under the flag stones, made me imagine them as flies on a pond surface playing on the surface like light fingers on a drum. So that begged the question- What, below this surface, is going on?

The experience provoked thoughts about what happens under your feet that we don’t usually think about:

The ground is like a vibrating surface – when you tap your foot

Is there just a massive sound that is inaudible to us beneath our feet?

Was it the trees and the roots (making the sound)?

Opens up the earth beneath your feet

Thought I heard the worms

Projection: Sound vibration has no boundaries. It goes right through the earth and permeates under oceans and cities at low frequencies we cannot hear but feel.(natural hum of the earth 1Hz and below and 1-7Hz cultural and natural noise (see journals). When we listen to the radio we imagine where the sound has come from. And like listening to the radio, the ephemeral qualities of hearing sound allows the listener to be both intimately close up in detail to all its’ qualities, and project our thought or imagination to its’ source, and the course of its’ travel to our ears.

Some people thought of themselves in relation to the planet:

With people clomping and the cars you feel the weight of the things on the earth

We leave a heavy footprint even though we don’t mean to

Like I’m underground- having something over the top of me

I will walk more softly from now on

It makes me feel bigger – makes me feel vast

Meaning and reality: The distortion of sound traveling through the ground,(faster than in air) where you don’t see exactly what you are used to seeing with the sound you hear, gets us to re-examine our presumptions about our reality that we take for granted. Perhaps this process, a mismatch of eye an ear, ‘takes apart the mechanism of meaning’ (feed back).

You hear people before you see them

Interesting relationships with what you’re seeing and what you don’t hear

Looking for connections with what I could see and what I was listening to..

The sound experienced as vibration takes apart the mechanisms of listening to it’s elemental components and reminds us of it’s process – when shaking our bodies’ bones as well as those in our eardrums.

Solid Listening

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Earlier this year I went to Redcliffe Caves: a labyrinth of tunnels under the city by the Bristol Docks, and Charlotte Heffernan and I put geophones in the walls of the underground caves to listen to the sound that could be heard. We couldn’t hear very much: mostly very faint traffic sounds and electrical buzzes. We did hear muffled signs of life above our heads. We were directly under streets and houses and a pub. When we drove away we noticed people in the pub drinking. We thought of the direction of the tunnels and realised that they had made those faint sounds – the ones we heard underground. They reminded me of the muffled sounds you hear through walls and doors and even from under the bath water when you are a child.

‘The faint underground sounds seemed somehow amplified and more potent in their remoteness deep down in the quiet underground.’ Words from journal  2010

I made an installation for the sound festival Audiograft (http://www.audiograft.com/ ) after thinking about these small sounds heard remotely through the big chunk of rock and clay.  Through Walls was a sound piece where people inside a room could hear sounds through the walls and outside sounds through the large plate glass window.

 

Outside the room speakers played sound directly into the walls. They played a track of random domestic sound I had picked up in my house into the wall. These sounds were hardly audible in the room but heard if you put your ear or a listening device to locate them on the wall. Listeners experimented by pressing their ears on the walls or used listening devices: tumblers, funnels, horns, stethoscopes etc. The walls and plate glass surfaces acted both as amplifiers and filters to the sound heard through them.

 

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People fed back their thoughts. The instruments became ‘extensions’ to their own ears. The act of creating new ‘big ears’ started people thinking:  What sounds are we listening to? Where is it coming from? The instruments transformed the sound we could hear with our ears. It was commented that it showed how extremely efficient our own ears seem, inferring that we are not even aware of the transforming qualities our own ears have.

Sound brought clear associations of the past. The listeners’ had memories of sounds heard in the past through materials such as walls, water and glass. We have, it seems, been receiving our sound from our earliest memories from all the different materials around us.

Big Sound Waves – getting the measure!

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The Pipe

My idea was to show a large-scale resonator (pipe) that would describe how long the LIVE sound

wave   actually was, and we would hear and experience the vibrations of the sound wave as it

resonated  in the pipe.  I was aiming to play a 16 meter long sound wave!

I set up a geophone that played live sound from the ground into a speaker at the end of a pipe.

A 4 m  sewage down pipe was the largest I could get my hands on at this time. The geophone

was  picking upthe sound of the traffic 80 m away, across Headington House Gardens at

Oxford Brookes  University.

I found out that sealing the end of a pipe would create a lower frequency, in fact a quarter of the length of a sound wave in a sealed pipe.  So our 4m sealed pipe resonated the same as the whole 16m length of sound wave in an open or un sealed pipe, amongst other frequencies. Ours was not an exact science as far as the sealing up of the pipe went. (With an outside setting there were not exact workings regarding end correction etc.)  I had some helpful advice from musician and electroacoustician, Sarah Angliss and artist and technologist Mike Blow, who played a sine wave into a carefully sealed pipe and had the maths to prove it.

http://www.sarahangliss.com/

http://mikeblow.wordpress.com/

Open 16m pipe at  21Hz (Just audible)

4m long sound wave resonates best in an open 4m pipe at 85Hz (You can hear this)

A 4m sealed pipe resonates ¼ of a 16m sound wave at 21Hz  (Just audible again)

http://www.sengpielaudio.com/calculator-wavelength.htm

So what were we listening to? Here’s some of the sound and vibration if you have good bass speakers or a sub.

[audio:https://shirleypegna.com/wp-content/uploads/2011/01/pipe-blog-sound2.mp3|titles=pipe blog sound]

Revealing-   Showing –   Illustrating –   Demonstrating –   Informing –   Illuminating –   Amplifying

So, did it work? It played sound, and different frequencies were resonated. It didn’t work in the way I had imagined, because these details, in my head, were not obvious to the observing audience. The feedback was varied: it had encouraged some people to think to of the space under their feet, to imagine a massive inaudible sound in the earth, to question the trickery of the equipment, think of the ‘ground as a vibrating surface’, and importantly question the need to standardize the equipment in order to understand what I was listening to.

It posed the question: When is an event a demonstration of science, and when is it art?  Is there a difference and does it matter? Sound artist Alvin Lucier, in an interview with Chris Buck in the Wire (issue 245 2004) states, ‘Scientists often miss the poetic beauty of nature and the sensual experience of natural forces…. I understand the (scientific) principals more because I’ve used them in a piece experientially rather than theoretically’. With that in mind it’s definitely worth checking out these works:

Katie Patterson – Moonhttp://www.wired.co.uk/wired-magazine/archive/2010/05/play/katie-paterson-the-universe-s-official-artist?page=all

Mark Bain – Live Room:Transducing Resonant Architecture

http://www.nettime.org/Lists-Archives/nettime-l-9908/msg00023.html

Bill Fontana – Speeds of Time

http://www.resoundings.org/Pages/Speeds_of_Time_new.html

Roberta Gigante  OrgOOn in  Ghent Docks

http://www.we-make-money-not-art.com/archives/2010/05/organoon-at-electrified.php

I was sorry to miss this festival in Ghent last year, where Roberta Gigante was playing sound into 30m long pipes. Open at one end they would be resonating at a frequency of 11.43 Hz.   Given the pipes could be sealed frequency would be =3.81Hz and the sound wave 90m long. That is some length of sound wave!

If anyone knows the whereabouts of some monster sized pipes in the UK, then let me know as I ‘d be delighted to use them for some sound experiments.

Roberta Gigante  OrgOOn          photo: Reinout Hiel for Vooruit

Sizing up Seismometers

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I drove down to North Devon to Hartland Point with a friend Charlotte, to see a seismometer in action.

I wanted to find out what I was hearing with the microphones I had put in the ground in Bristol? (Piezo and AKG pick-ups and a geophone).

What was I hearing from them? How could I find out where the sound was coming from? The understanding of this long distance low frequency microphone would help me find out.

Hartland  Magnetic Observatory

The seismometer in it's case in the ground

The seismometer in it’s case in the ground 6 feet down on bedded on solid rock

http://www.google.co.uk/search?q=hartland+observatory+north+devon&ie=utf-8&oe=utf-8&aq=t&rls=org.mozilla:en-US:official&client=firefox-a

I was right about seismometers picking up sound waves traveling long distances from other continents, which was mind blowing, but surprisingly even thelocal dog walkers had an effect on the seismometer. This was strange, but of course they were making their own mini tremors with their foot -falls.

Here’s the data read from the seismometer – showing a blob on the left

I stamped my foot and the seismometer reacted instantly even though it was out side the building 60 METERS AWAY!!

This clever instrument could pick up the quieter range of sounds in the ground. It would be capable of monitoring 0.01Hz-100Hz, and the (inaudible to human ear –which hears from approx 20Hz) natural Hum of the earth (0.02Hz- 7 Hz).

And this being lower than the cultural man made sounds from cities and trains (in particular) that start at approximately 1Hz.

Look here for more pictures : http://www.guralp.com/products/

While I was getting my head round the image of a sound wave making it’s way to effect this instrument, in a box 6 foot under the ground, from several thousands of miles away, I felt the mighty physicality of the sound wave traveling over such a distance was certainly a planetary scale event.

I start to think of earth as a lump of humming, quaking, vibrating buzzing rock.

The work by artist Floriain Dombois, puts this global phenomena into context with pictures of measuring devices in sheds and compounds and seismic stations from different 60 countries. (Seismic Stations   Global seismographic Network (GSN) 59 of them.

http://www.iris.washington.edu/IRISquery/bin/gsn_sta_s.pl )

Up in the Edinburgh the British Geological Society monitor the signals that get picked up from round the UK, those from the UK and those that have traveled from other continents. With data from different station’s the origin of the tremor can be plotted. Primary, Secondary and surface waves, and their different trajectories through and round the planet are compiled and compared with data from other countries. We hear the effects of these forces more often on the news, from places that suffer human tragedy from the destruction caused by the planet.

Here’s pictures of sound through the earth’s mantle:  http://en.wikipedia.org/wiki/File:Earthquake_wave_paths.svg

Here’s some big tremors: http://www.iris.edu/seismon/

Here are some recent tremors: http://www.iris.edu/seismon/last30.html

Here are seismograms at different stations: http://www.iris.edu/cgi-bin/wilberII/wilberII_EnO_page4.pl?evname=20110122_172924.4.spyder

That afternoon we learnt that forces effect our planet -not only vibration working from the middle of the planet: from the movement of tectonic plates (making quakes and tremors), but also the geomagnetic forces from round the outside of the ionosphere working in.

http://www.geomag.bgs.ac.uk/education/earthmag.html

It was described to me recently that we, on the surface of our planet, are like innocent children or kittens, to whom things happen. In this case vibrations and forces from outside our local view.

We noticed the amazing display of Heath Robinson looking gadgets/instruments all over the station.

Although we came to see the seismometer, the observation station mainly monitors geomagnetic forces, measuring slight changes in the earth’s magnetic field, and has done for over 100 years (I found a bound record book dated1865). They moved from near Kew Gardens / London in 1957 when the train line was built and started to interfere with the instruments.

Records were meticulously kept for posterity, hand drawn in dusty volumes reminding me of nautical maps of uncharted seas.

On the head land with the on shore breeze, Steve, the manager who kindly showed us around the Observatory, describes how the latest magnetometer no longer needs a whole building, being small, digital and self heating.

I felt inspired to use the geophone we had brought, and was advised by Steve, that a good place to listen to natural sound, was through rock, and the ancient granite rock of the cliffs and harbour wall down the road at Hartland Quay.

Our geophone is an SM24 that picks up signals from 10Hz-240Hz.Like the seismometer has a capability of 2D and and 3D surveys, picking up sounds from all directions, and has a different mechanism to the seismometer. Have a look at it

http://www.geophone.com

It turned out we would have heard the sound of the sea, pounding on the ocean floor off Hartland Point, as it added to the natural din of sound in the ground. I never had thought of the sound of the sea emanating INTO the ground before, and even, I fancy, mixing with the earth’s natural low hum, and maybe the sound of more localised quarries and train lines, and low frequency signals from much further a-field, but unfortunately we found we had run out of time to make some good recordings and had to return home, so leaving our recording for another day.

Listening To Sound in the Ground

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Earlier this year I started listening to sounds from the ground, and used AKG and PIEZZO microphones attached to metal sheets and shoved into our allotment clay soil to pick up and listen to what sounds  I could.

The results were intriguing, and question arose about the behavior of the microphones and what I was exactly hearing.

What was the sound source, and what was the low frequency white noise I was picking up?

Questions came up like -Do totally submerged microphones pick this white noise up, and what were the sound frequencies from the local traffic and what was from sources further away?

Here’s the spot near the Clifton Suspension Bridge where I put in the metal plate, and below  an AKG pick up microphone on a rock face not far from the road by the bridge.

As I did more tests, it became clearer to ask testable questions  – using comparisons. So comparing different sized metal plates, burying them differently in the ground, setting them out at different distances from the road, told me a bit more about the sound.

Questions started forming like: what sound came from above ground and what from underneath, which settings on the equipment should I adjust? In fact how did the different equipment compare?

I did distrust my equipment somewhat and I looked for other microphones I had heard of. My quest to look into equipment had begun.