The Boston Symphony Orchestra Returns to Live Performance at Tanglewood
Weekend Live Music Preview: 9/17-9/19

EMPAC Wave Field Synthesis Opens TIME:SPANS Festival at the DiMenna Center

Time Spans Wave Field SynthesisAcoustics are a funny thing. In most concert halls, you hear the instruments in your head in relation to their position on the stage, regardless of where you sit: violins sound as if they come from the left, basses from the right, winds and brass behind. But in some older, curved halls - I'm thinking of Carnegie in particular - there are some seats where a disembodied oboe or flute sounds as if it's coming from the right, or even from behind you. These acoustic quirks (which also appear in Whispering Benches) are generally eliminated now with the help of acoustic engineers, who are paid handsomely to ensure every seat has a clear, balanced sound. 

With amplified music, sounds are generally limited by the number of channels in any given loudspeaker array: a stereo system has two channels, a typical home theater system has seven, a movie theater has 10. But, all of these systems project sound in only one direction, meaning you have to position yourself in the absolute center of the room in order to get a "true" surround sound experience. And, even then, the experience is mostly individual sounds bouncing around the room (i.e., Stockhausen's 24 channel work Cosmic Pulses.)

Enter Rensselaer Polytechnic Institute's Experimental Media and Performing Arts Center (EMPAC), which works with a technology called Wave Field Synthesis that claims to have the ability to project sound in real space, much like in an acoustic concert hall. The technology, which was developed at the Delft University of Technology in the late 1980's, has been used in live performance before, but with inconsistent results. EMPAC's innovation is to use a modular array of 558 mini loudspeakers, grouped into 18 modules of 31 speakers each, plus subwoofers. The technology - which involves the manipulation of sonic wave fields -  is too complicated to explain here, but working with software developed at IRCAM in Paris, the EMPAC array enables composers to project high resolution sounds not from a single source, but from different locations around a room. 

Wave field synthesis time spansThis weekend, EMPAC, which is currently closed due to COVID, has brought their loudspeaker array to the DiMenna Center for the opening of the annual TIME:SPANS festival of new and experimental music. Due to space and technological restrictions, EMPAC has only brought half of the array to the city: approximately 250 speakers, all lined up in a horizontal row. In his introductory remarks, EMPAC director Johannes Goebel encouraged us to move around the room during the performances in order to experience the full impact of the technology. (At EMPAC, Goebel told me that the full array has been deployed on the ceiling and along multiple walls.) 


EMPAC and the Earle Brown Foundation commissioned four new works for the array which, in what seems to be just a happy coincidence, were all written by women. In Pamela Z's Sonant Topography, her voice mostly came from the direction of the speakers, but once or twice I did experience some genuine displacement, where the sound seemed to enter my left ear even though I was standing with my right ear to the array. Miya Masaoka's Seeking a Sense of Somethingness (Out of Nothingness) achieved the same effect with a bassoon (played by Clifton Joey Guidry III), which seemed to float in space. Nina C. Young's Phosphorescent Devotion built upon a foundation of voices and field recordings to a rapturous tintinnabulation. Bora Yoon's intimate, confessional SPKR SPRKL opened with a direct engagement ("Hey. Hey, you.") then moved through a disturbing series of warlike sounds (bombs, chains, helicopters flying around the room) before finally offering glee in the form of a glitter ball. 

Performances on EMPAC's Wave Field array continue through Sunday. Each performance last 70 minutes and are limited to 25 audience members, all of whom must show proof of COVID-19 vaccination. The TIME:SPANS festival continues through August 29 with performances by JACK Quartet, Tyshawn Sorey, Yarn/Wire, Wet Ink Ensemble, and others. Tickets and additional info on the TIME:SPANS website