Wild Energy gives access to the inaudible, vibrations in the ultra and infra ranges emanating from sources which affect us fundamentally, but which are beyond our audio perception, many of which are creating our planet’s environment: the sun, the troposphere and ionosphere, the earth’s crust and core, the oxygen-generating trees – everything deeply integrated, forming an inaudible web in which we move, through which we live and on which, therefore, we depend. It is our sense that through these sounds one can feel the energies generated, not as concepts but as energy-fields moving through one’s body. A generating image for the piece is of the Cedar Walk’s trees funneling these energies into the oxygen we breathe as we walk near them, or lie under them.
Wild Energy is a fifty minute loop which begins with solar oscillations recorded by the SOHO spacecraft, sped up 42,000 times, and ends with ultrasound recorded from the interior of a scots pine tree, slowed down 10 times, to make them audible to us. We are deeply grateful to the scientists who so generously gave us access to their sound files and permission to use them. The many sounds and their sources are described below, in order of initial appearance:
Solar oscillations are pressure waves which travel through the body of the sun, causing ripples on the surface which the SOHO spacecraft is recording (NASA and the European Space Agency). Alexander Kosovichev and colleagues at Stanford University’s Solar Oscillation Investigation program, sped up 40 days of solar data by a factor of 42,000, bringing them into the audio range.
Kilauea volcano – gas vents, tremors
Pressurized gas is released as magma rises to the surface, creating pressure fluctuations, infrasound. Gas bubbles contribute to the sounds produced, which can resonate cavities beneath the surface. Infrasound signals recorded from tremors, explosions, fissure eruptions and bench collapses have been recorded by Milton Garces and his team (the Infrasound Laboratory, the University of Hawai’i) in recent years, particularly at the Pu’u O’o and Halema’uma’u vents. Of the recordings we have used here most have been sped up 200 times, a few 100 times.
Chorus waves and whistlers
Very Low Frequency Chorus Waves are electromagnetic waves caused by intense plasma waves generated in the radioactive Van Allen Belts in the magnetosphere surrounding the Earth. Whistlers (also VLF electromagnetic waves) are generated by lightning and move along Earth’s magnetic field lines, between the two hemispheres. Their high frequency components travel more rapidly than their lower frequencies, creating a falling tone. “This is what the radiation belts would sound like if we had antennas for ears” commented Craig Kletzing of the University of Iowa’s Radio & Plasma Wave Group who gave us these recordings and also a recording of AKR emissions. NASA’s two Radiation Belt Storm Probe satellites, together with the University’s EMFISIS receivers recently sent back recordings transmitted in stereo, a new development enriching both the sound and the data picture. Both whistlers and choruses occur at frequencies within our hearing range, and are audible once converted by the receivers.
Sei whales are “the third largest baleen whale, found in subtropical, temperate and subpolar waters worldwide.” (DOSITS) Having been extensively hunted they are now an endangered species, with an estimated current population of 80,000 whales. This whale was recorded by Arthur Newhall (the Woods Hole Oceanographic Institution), near the continental shelf break east of New Jersey, just south of the Hudson Canyon.
Dr. Newhall has posted this recording on the University of Rhode Island’s DOSITS (Discovery of Sound in the Sea) website where many interesting oceanographic sound samples may be heard.
The ground shaking of earthquakes is very low frequency, recorded as seismograms which may be sped up to bring them into the hearing range. Arrays of seismometers are used at different distances from the epicenter, which affects the pitch ranges, in addition to the quake’s perceived strength: Because high frequencies lose energy and are dissipated faster with distance than low frequencies, higher pitches and sharp, explosive events indicate a shorter distance from the seismometers, and the deep rumbling ones a greater distance.
The first quake in the installation was the Parkfield quake of 2004 (on the San Andreas Fault), recorded by the USGS. The subsequent quake recordings were given to us by Ben Holtzman, at the Lamont-Doherty Earth Observatory, Columbia University and Jason Candler (www.seismicsoundlab.org): Sumatra 2002, and the Sumatra-Andaman Island great quake of 2004, Japan 2007, and also from Japan 2011 – the ‘tsunami’ quake.
Trees: ultrasound emissions 1
Trees continuously pump water out of the ground through water columns in the xylem layer up to the leaves, enabling photosynthesis to take place. When trees become water-stressed, in drought or other dry conditions, unusually high levels of tension in the water columns lead to their rupture. Air bubbles are formed, blocking water flow and bursting; one indication of this is the ultrasonic acoustic cavitation clicks the trees emit. Biophysicist and tree physiologist, Melvin Tyree, has carried out pioneering research on this and other aspects of water transport in trees and compiled this sequence of cavitation clicks, each distinct and individual, which he sent to Annea over a decade ago. Here is an illustration of the process.
These oceanic vents form when seawater (35.6 degrees F) penetrates cracks in the seabed, moving down toward magma bodies where it absorbs intense heat and minerals. The now superheated water (up to 860 degrees F), which is rich in hydrogen sulfide and minerals, then bursts back up through the seafloor and into the ocean to complete the hydrothermal cycle. The hottest of these vents are called black smokers (named for the black plumes they produce).
Long thought to be silent, hydrophone arrays deployed near the vents have recently revealed that they generate intense broadband acoustic signals at frequencies from 5 to 500Hz, and also “narrowband tones from 10 – 250Hz… Each vent has a unique acoustic signature” (dosits.org). Timothy Crone and colleagues at the Lamont-Doherty Earth Observatory have been recording at the Sully and Puffer black smoker vents in the Main Endeavor Field of the Juan de Fuca Ridge, two hundred miles off the coast of Washington State and gave us filtered examples of the tones generated as the vents’ physical structures resonate.
The echolocation calls bats emit are in the ultrasound range, so these have been slowed down. The following bats (found on Shockwave-Sound.com) are included in Wild Energy:
Pipistrelle bat – we do not have identification for the precise type.
California Myotis bat – prefers desert habitat, known for the great agility of its flight patterns.
Silver-haired bat – the largest of New York’s bats with a wingspan which can reach 16 inches, found largely in the Adirondacks.
Big brown bat – the largest cave bat in New York State with a wingspan of almost 13 inches, and is the most commonly seen summer bat.
Big brown bat hunting tiger moth: This remarkable recording by Aaron Corcoran of Wake Forest University is of a big brown trying to catch a Grote’s tiger moth (Bertholdia trigona) using echolocation. The moth, in turn, is using ultrasound bursts to jam the bat’s echolocation capability – i.e. interference. The recording has been slowed down ten times to bring it into our hearing range.
Auroral kilometric radiation emissions occur along magnetic field lines, and are generated by high-energy particles shooting through Earth’s magnetic field. They are associated with aurora displays, and seem to occur “about 3,000 miles above bright regions” in the auroras which arise in polar regions, University of Iowa researchers Robert Mutel and Donald Gurnett noted in 2001.
Tree ultrasound emissions 2: Scots Pine
Cavitation clicks are not the only ultrasonic acoustic emissions (UAE) from trees. Roman Zweifel, Fabienne Zeugin (Swiss Federal Institute for Forest, Snow and Landscape Research WSL) and Marcus Maeder (Institute for Computer Music and Sound Technology, Zurich) have been recording a variety of other emissions from within scots pines, discovering a relationship between the intensity of the emissions and changes in stem radius, for example. This recording, made by Marcus Maeder in 2012, together with an earthquake in Sumatra (recorded in 2004 by Ben Holtzman), can be heard at the end of Wild Energy.
Annea Lockwood is known for her explorations of natural acoustic sounds and environments, in works ranging from sound installations to concert works; she has worked with Bob Bielecki a number of times over the years. Her music has been presented in many venues, including the Whitney Museum, MACBA Barcelona, the Sonic Acts Festival Amsterdam, Roulette, and The Kitchen, NY. She is a recipient of the American Music Center’s Henry Cowell Award for composers exemplifying “Henry Cowell’s spirit of innovation and experimentation…” and a professor emerita of Vassar College.
Bob Bielecki has worked in the media arts field for more than forty years, creating unique instruments and sound designs for installation and performance. He is known for his innovative use of technology to develop distinctive electronic effects and environments and is engaged in ongoing research in psychoacoustics, sound localization, and 3-D audio.
Bob Bielecki has worked with many artists including John Cage, Alvin Lucier, La Monte Young and Pauline Oliveros. His association with Laurie Anderson dates from the mid-1970s and he has worked with Stephen Vitiello and Annea Lockwood since the 1980s.
He produced and engineered the groundbreaking media-arts residency program, ZBS/AIR, and helped to pioneer the field of binaural radio. A recipient of grants from the Andy Warhol Foundation and the New York State Council on the Arts, he is an Associate Professor of Music at Bard College and serves on the faculty of the Bard MFA Program.