This sound is on fire

Many aspects of a firefighter’s work are not quite like the movies, and locating each other is one of them, according to a recent story from KUT News in Texas.  Visibility is poor or nonexistent in a real fire, so firefighters often have to rely on sound rather than vision.  A Personal Alert Safety System (PASS) is a device that emits a loud audible alarm if the wearer stops moving for more than a few seconds, allowing colleagues to come to the rescue.  Researchers at the University of Texas at Austin are working on ways to improve this system, which despite saving many lives doesn’t always work as well as it could.

For starters, an active fireground is a loud, noisy place, from things like sirens, power tools, engines, and the fire itself.  But beyond that, heat can do funny things to sound—hotter and colder parts of a room make sound travel faster or slower, and these changes in the speed of sound can actually bend sound waves that would otherwise travel in a straight line.  (Similar effects occur outdoors when the air temperature varies with height, such as being able to hear campers far away across a lake that cools the air.)  This heat refraction can wreak havoc with audibility and locating the source of a PASS beacon.  The current UT research will provide valuable insight into the sensory environment within a fire scene, and how compensation might be made for some of these acoustic challenges.

 

Did you hear that meteor?

This past weekend, the Perseid meteor shower reached its peak overnight between Sunday and Monday.  With a little patience and clear skies, the electromagnetic radiation in the visible spectrum that meteors release is easily seen.  But did you know that meteors also release very low frequency radio waves, below 30 kilohertz? According to livescience, going back hundreds if not thousands of years, people have claimed to hear sounds of meteors as they raced across the sky.  The very low frequency radio waves travel at the speed of light (not at the speed of sound) and arrive at the same time observers see a meteor passing overhead.  However, the radio waves need a transducer to could create a sound that is audible to people. This phenomenon is known as electrophonics, and in order to study it further, physicist Colin Keay created sounds in ordinary objects by exposing them to very low frequency radiation in a laboratory. Lightweight, membrane-like objects such as aluminum foil, foliage, thin wires, even dry frizzy hair produced sounds that were easily heard.

2012 Geminid Meteor Over Texas

Never having heard this before, we thought we would head out to Long Island to try and hear it for ourselves. We saw and heard a few things…First, there are quite a few sky-watchers in New York, which unfortunately meant that second, people noise and car stereos are louder than the sound from meteors.  Also, being by the beach, the sound of the ocean waves were also louder than the meteors.  Even if we couldn’t hear them this time, and although there were a few passing clouds, meteor showers still create a wondrous sight.  We will just have to make plans to go somewhere a bit quieter next time.

 

But I know what I hear

This week, New York’s Museum of Modern Art is opening its first major exhibition of sound art, “Soundings: A Contemporary Score”.  Through November 3rd, visitors will be able to immerse themselves in auditory pieces designed by sixteen of the most innovative contemporary artists working with sound.

Forty-Part Motet

Not to be outdone, on September 10th the Metropolitan Museum of Art will present Janet Cardiff’s “Forty-Part Motet”, pictured above.  This first foray into sound by the Met (to be installed in Fuentidueña Chapel at The Cloisters) combines forty separately-recorded voices from forty loudspeakers into a 16th century choral ensemble, a synthesis that the New York Times notes has brought visitors to tears.  The Times also provides audio clips from the MOMA exhibition, noting that “while you can close your eyes to an image you hate, you can’t close your ears to a noise”—a risk without a parallel in the visual arts.

New tunnel between 33rd St and 40th St?

Well sort of….As part of the NYC Summer Streets 2013, artist Rafael Lozano-Hemmer will install Voice Tunnel, which includes 360 spotlights controlled by a special intercom located at the center of the tunnel that passses under Park Avenue between 33rd and 40th Streets.  The intercom will record public  participants voices and influence the intensity of the light – louder speech will increase the brightness of the lights.  The intent is to create ‘Morse-code like’ flashes based on the sound pattern and volume of speech.  The individual voices will also be audible on 180 loudspeakers located along the length of the tunnel.  It will be open on Saturdays between 7 am and 1 pm Aug 3rd, 10th and 17th.

The content of the piece will change constantly as participants come and go.  We are curious to hear how the reverberation within the tunnel and potential added acoustical absorption of people in the tunnel will influence the piece. That, and of course it is always neat to go places on foot where you can usually only drive…maybe we will see you there.

New York Noise

After over two years of work, we are glad to say that the final report for our project Wind Turbine-Related Noise in Western New York has been published.  Funded by the New York State Energy Research and Development Authority (NYSERDA) and the Electric Power Research Institute (EPRI), and co-produced with EPRI and Colden Corporation, the study presents a detailed and long-term look at noise levels and resident satisfaction near a modern, utility-scale wind power facility in Wyoming County, NY.

Wind Turbines

The findings of the study fill a gap in the available wind turbine noise research specific to New York State, and include a separate Syracuse University policy paper with specific and actionable advice for a non-technical public policy audience.  Both the Final Report (13-03) and the Policy Paper (13-03b) can be found at the NYSERDA R&D site, and we plan to present the project at the Wind Turbine Noise 2013 conference this August in Denver, Colorado.

MakeMusicNewYork

Today is MakeMusicNewYork, a FREE live music celebration on the longest day of the year! check it out….

mmny-summer-2016