Odd Sympathy

Dutch mathematician and physicist Christaan Huygens observed 1673 that two pendulums mounted on the same beam will come to swing in perfectly opposite directions, an observation he referred to as odd sympathy which in modern times is known as resonance. The tendency of two pendulums to synchronize, or asynchronize, is also refered to as the lock-in-effect. A beautiful example of this phenomenon is brought into being with metronomes in the following video.

 

 

Christoph Cox and Daniel Warner - Audio Culture

An almanach packed with essays and writings of such different sources like early modern music pioneers Russolo, Varèse, and Cage next to DJ Spooky and Kim Cascone, the book traces back many cross references in all strains of the musical avant-garde be it experimental, minimal, improvised, electronic or from the DJ culture. A must on every book shelf of the ones addicted to a new audio culture conceived as “a discourse, a loose collection of terms, concepts, and statements gathered from across the cultural field. The discourse not only challenges aesthetic distincitions between ‘high art’ and ‘popular culture’, it also flattens traditional hierachies between ‘high’ and ‘low’ ventures for publishing.” There is a very good review here, that says everything.

Ice Sizzle

Glacial ice consists of snow that has been extremely compressed and compacted. In the case of the inland ice in Greenland, this process may stretch over thousands or even millions of years before the ice is pushed into the sea by a glacier. As the layers of snow pile up, tiny bubbles of air are trapped and put under enormous pressure by the weight of the surrounding ice. When the glacial ice finally melts in the sea, these tiny bubbles of air are released with a quiet, explosive popping noise, adding up to a many-voiced sizzling. The icebergs that drift in the Arctic give off a constant sizzling sound which is loud enough to determine their position from under water. The phenomenon was first noted by the crews of submarines. It is also known as “bergy seltzer” due to its resemblance to the sound of fizzy drinks.

I recorded the audio excerpt in Greenland 2006. I collected some ice chunks from icebergs in a plastic bag during a ship tour and stored them in a bar for some hours before returning to my hotel room. Surprisingly the ice was not melted, there was not even water in the plastic bag. I put the ice scraps in the bathtub and recorded the sizzling with an underwater microphone. Later at home I applied a lot of noise reduction and transient designing to the recordings to get the sound that you can hear in the above MP3.

Live Stream from below Antarctic Ice

The german Alfred-Wegener-Institute is transmitting a MP3-livestream from Antarctica. They put four hydrophones 70 m underneath the shelf ice and 90 m above the ocean ground through drilled holes in the thick ice sheet. In close proximity to the open water the microphones catch the calls of sea mammals living in this remote region. The scientists in their homebase Bremerhaven are able to analyze the behaviour of whales and seals just as it happens. Only occasionally the electronic-sounding concierto of the seals is interrupted by calving glaciers and colliding icebergs. This recording though baffled the scientists because it doesn’t belong to any sea creature known and nobody heard ice breaking like this before. It’s your guess. The Alfred Wegener Institute gratefully let me use this recording in my piece frost pattern.

Japan’s Melody Roads Play Music as You Drive

A team from the Hokkaido Industrial Research Institute has built a number of “melody roads“, which use cars as tuning forks to play music as they travel. The concept works by using grooves, which are cut at very specific intervals in the road surface. Just as travelling over small speed bumps or road markings can emit a rumbling tone throughout a vehicle, the melody road uses the spaces between to create different notes.

Eric La Casa - Air.Ratio

Everybody knows the constant whisper of air vents in hotel bathrooms or in restrooms of public places, a permanent sonic background to many modern buildings. The network of mechanized ventilation imposes a sound continuum on modern architecture that  provides an image of the rationalization of our interiour living conditions. Eric La Casa collects 30 recordings of such ventilation systems for his CD air.ratio that he made in different locations all over Paris. First the sound stamps are assembled in a quick sequence as a reference point, 2 seconds each location, then the 30 ventilation recordings are presented each for 2 min and finally followed by a minute of silence. While listening to the amplified humming of ventilation, certain psychoacoustic effects appear: one might hear voices or strange instruments in the modulated white noise of the air vents and think, those may be transmitted from other rooms in the building. At least I can easily imagine to start hearing ghosts if exposed to steady sounds like this. Eric remarks that this CD is intended to be an object without distinctive function. Neither scientific nor musical, this project could hold as an art installation (I envisage empty cold bathrooms with white tiles, in which the sounds are played) and by the same token as a minimalistic piece of sound art (just like the piece buildings by Francisco Lopez). Out at sirr records.

Tikal at Dawn

In March I travelled Mexico and Guatemala. The most spectacular Maya-site is probably Tikal in the Guatemalan jungle. I had the opportunity to stay at gran plaza in the center of the ruins about 45 min. before gates open at dawn. My guided group rushed to the temple with the best sight over the forest canopy, while I was alone with a lot of wildlife in the heart of this abandoned city. The picture above shows what I saw while I placed my microphones on an opposite temple. There are a lot of parrots, the montezuma oropendola again, that I already got acquainted with on the Cano Negro in Costa Rica, a Guatemalan turkey and - indeed - the notorious howler monkeys.

The Noisy Neighbors Who Live Underwater

New York Times reports that in Florida the mating calls of a fish species called black drum resonated through the homes of retirees in Cape Coral, leading to the neighbors to push the City Council to eliminate the noise. Nobody would believe that the source of the noise reverbaration was fish. ”For most fish, the sonic mechanism is a muscle that vibrates a swim bladder not unlike our vocal cord. The bladder is a gas-filled sac used for buoyancy, but it can also be used as a sort of drum. The Gulf toadfish contracts its sonic muscle against its swim bladder thousands of times a minute to generate a loud drone. At nearly three times the average wingbeat of a hummingbird, toadfish have the fastest known muscle of any vertebrate. Cusk eel rattle bones against their bladder, but clownfish have a sonic ligament they use to “chirp.” You can read the full article and hear some sound examples here.

 

Dispersion of Sound Waves in Ice Sheets

I made this sound recording of a frozen lake in the winter of 2005/06 in the area around Berlin. Frozen lakes are known to give off most noise during major fluctuations in temperature: the ice expands or contracts, and the resulting tension in the ice causes cracks to appear. Due to the changes in temperature, the hours of morning and evening are usually the best times to hear these sounds. In my experience, thin ice is especially interesting for acoustic phenomena; it is more elastic and sounds are propagated better across the surface. Snowfall, on the other hand, has a muffling effect and the sound can only travel to a limited extent. The ice sheet acts as a huge membrane across which the cracking and popping sounds spread. Underwater microphones proved especially well-suited for these recordings: in a small hole drilled close beneath the surface of the water, the sounds emitted by the body of ice carry particularly well. The most striking thing about these recordings is the synthetic-sounding descending tones caused by the phenomenon of the dispersion of sound waves. The high frequencies of the popping and cracking noises are transmitted faster by the ice than the deeper frequencies, which reach the listener with a time lag as glissandi sinking to almost bottomless depths.

Listening to the Environment at higher Volume

“The microphone is an instrument which acts toward the ear as the microscope does to the eye. It will render evident to us sounds that are otherwise ablolutely inaudible. I have heard myself the tramp of a little fly across a box with a tread almost as loud as that of a horse across a wooden bridge.” W.H. Preece

One of the basic effects of “acousmatic listening” is probably underestimated: hearing our environment at higher volume through the headphones of mobile recording devices, is one of the most revealing experiences. When playing back field recordings of places that we are familiar with, we hear the environment in a different way, deeper, with more detail, with an integral perspective. The type and position of the microphone or the time window we choose of a certain sound recording etc. are already artistic or subjective decisions made during the process of recording, but for the perception of the acousmatic recording the difference in volume compared to the „real“ experience is the most powerful. And this is even more true with recordings of single sound events, that we do in studios with the possibility of close up micing and the exclusion of atmospheric „disturbances“ from background noises. The quietest sounds of any sound bodies can produce a totally different aural image when the level is pushed up to the maximum. It appears to be common sense but we should consider this as one of the strongest instruments of sound manipulation (under the precondition that we do not want to use sound processing like time and pitch change and all the other effects common in digital sound processing today). One example to elucidate this: when I do sound recordings in public places and people approach me that are unfamiliar with what I’m doing, I let them listen through my headphones to the acoustic environment. Because the recording equipment already amplifies the soundscape at a certain level people are mostly very surprised by what they hear. They are able to listen to a well known place in a different way, they hear things they usually do not pay attention to. The headphones and the microphones are like acoustic magnifying glasses, from near by we can hear things that were hidden in the first place.