On Sferics

 Photo by James Fei, 2016.

Photo by James Fei, 2016.


When Alvin Lucier called me about helping him with a show in Marfa in 2016, he casually mentioned that he’d like to present Sferics as a live installation. “Do you think it will work?” Frankly, I wasn’t sure at the time. 

Sferics captures electrical impulses caused by lightning discharges, which can travel thousands of miles in the earth’s ionosphere. Depending on the distance traveled, the spectral content of the impulse can be offset, creating a range of sounds described as tweeks, bonks, and whistlers. Alvin’s original recordings were recorded in the Colorado mountains in 1981, using a pair of loop antennas to capture slightly different signals in stereo. 

I’ve been working with Alvin on a variety of pieces since studying with him at Wesleyan University in the nineties. When the performances are well done, they seem effortless and stripped of any superfluous elements, directing the audience’s attention solely to the idea at hand. Achieving this clarity, however, took a great deal of care, and I was always impressed by Alvin’s ability to instantly identify extraneous material, reducing the presentation to the essence of the work. 

Reviving Alvin’s older pieces often required some technical work. Sometimes electronics needed to be restored (e.g. his alpha wave amplifier for Music For Solo Performer and the galvanic skin response amplifier for Clocker), at other times new software is created, in the instance of performing I Am Sitting In a Room live. Sferics is particularly problematic because it is so dependent on the electromagnetic radiation at the location of the installation—the antennas will pick up any electro-magnetic wave, and it is nearly impossible to avoid the 60hz hum of electrical power distribution in most parts of the country. Even in the remote desert site in Marfa where we were going to install the work, there is a power line running along the edges. This was trouble. 

There are two common ways to pick up Very Low Frequency radio such as sferics, using either a whip or loop antenna. The former is more compact and omnidirectional. The loop, while physically unwieldy, is more directional, rejecting the sides relative to the front and back by roughly 30dB. This property is critical in tuning out AC hum and achieving a stereo pickup, and the low impedance of the loop should theoretically yield a less noisy signal. However, since I wasn’t sure how they would turn out until we tested them the day before the installation, I constructed a whip antenna amplifier for Marfa as well, just in case.

Graf_1_Antenna.jpg

Alvin’s original antennas were based on a design from Calvin Graf’s Listen to Radio Energy, Light, and Sound—a cross of 6’ pieces of wood with five turns of 22-guage wire evenly spaced apart. The ends of the wire loop are connected to a step-up transformer followed by an amplifier, which were simply the microphone input stages of his tape recorder when Alvin made his Colorado recordings. I replicated this antenna and ran a test in my backyard with a flat microphone preamplifier. My house in Oakland is one block away from the local power substation, so I figured that if I could get any degree of sferics to come through there, it would work fine in Marfa. 

Graf_2_Antenna.jpg
Graf_3_Antenna.jpg

The results were not promising—I could barely detect a hint of the characteristic popping static of sferics, and it was so deeply buried under the hum that I wasn’t sure about what I was hearing. It became clear that a filter to attenuate the AC-related signal was needed, but figuring out the implementation took some work—I didn’t want to use a computer-based system since the installation needed to run for at least 12 hours on battery power in the dessert, and the electromagnetic noise generated by the computer itself can be picked up by the antenna. In order to optimize the filter design, I ended up testing different digital filters on the computer with the very noisy audio recordings I made, balancing the need to reject hum without filtering out the sferics in the process. The most effective setting became the basis of the circuit design, which did yield noisy but passable results in my 60hz-filled backyard.  

 Photo by James Fei, 2016.

Photo by James Fei, 2016.

 Photos by James Fei, 2016.

Photos by James Fei, 2016.

Right up until the evening before the installation in Marfa, I had no idea whether the setup would work sufficiently well. With great anxiety, the antennas were assembled under flashlights, located as far away from the power line as possible, and plugged into the amplifier. Much to my relief, sferics came through loud and clear right away. With some adjustments to the orientation of the antenna, it turned out better than anything I could have hoped for. The installation ran overnight, with visitors listening to atmospheric radio as the sun rose in the desert. 

 "James Fei with Alvin Lucier at  Sferics  in Marfa," photo by Jennifer Burris Staton, 2016.

"James Fei with Alvin Lucier at Sferics in Marfa," photo by Jennifer Burris Staton, 2016.

"Alvin Lucier's Sferics in Marfa (2016)," 2018. Copyright of the author.