Any Sound from Anywhere – Experiencing Spatial Audio at EMPAC

From the very beginning of the design and development of the building in 2001, the acoustic properties of EMPAC’s main venues were designed to enable “any sound from anywhere.” The room acoustics were to accommodate a balanced and equally exceptional response to sounds coming from anywhere in the space, be they produced with acoustic instruments or with loudspeakers.

The Concert Hall, the two studios and the Theater are not only equipped with a technical infrastructure to distribute sounds to any point in each space, but equally to place an almost arbitrary number of loudspeakers anywhere in its volume.

The Concert Hall is particularly exceptional; it is the first large hall specifically designed to integrate the staging of acoustic instruments and ensembles throughout — around and among the audience — while reaching the listeners with the same sonic quality as when played on the main stage with loudspeakers suspended above, around, throughout, and sometimes below the audience.

We prefer the more general term “spatial audio” to “3D audio” since it encompasses stereo, quadrophonic, multi-channel, surround sound, ambisonics, wave field synthesis, and other technical formats. The term “3D audio” or “3D sound” has made a resurgence in recent years, especially in the video gaming industry and with interactive panoramic online videos, which strive to provide users listening with headphones with a sonic equivalent to the rendered 3D visual environments.

Spatial audio is a more general term. It encompasses the simulated (“virtual”) positioning of sound with two or more loudspeakers, the placement of actual physical loudspeakers in a space, as well as musicians with acoustic instruments placed throughout a venue.


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In another concert during the opening festival, Canadian composer Robert Normandeau set up and performed his electroacoustic works through a 40-speaker dome, placed above and around the Concert Hall’s center seating. The following video shows the installation of the loudspeaker dome.

Studio 1, Studio 2, and the Theater offer equally ideal environments for "any sound from anywhere." The acoustics in each venue are of the same quality as the Concert Hall. They are all exceptionally quiet with no noise from air handling or equipment (noise floor of RC 8), and variable acoustics to tune reverberation time. Any object, including loudspeakers or cameras, can be positioned on the walls or flown throughout the space, with network and audio connectivity extending building wide.

Many artists, musicians, and composers have utilized the flexible conditions for spatial audio at EMPAC to develop new work. The EMPAC team also developed a set of tools and new implementations to support the application of spatial audio, which the dedicated story Spatial Audio – Instruments, Technology, and Environments at EMPAC describes in more technical detail.

The following residencies and performances are provided as a few examples to give a sense of the diversity of projects and concerts that use extended spatial audio at EMPAC.

The Akousma Festival from Montreal performed three programs between 2011-14 at EMPAC. The first performance in 2011 used a multi-channel loudspeaker setup in smaller Studio 2. Shown on the following plan, the 2012 performance inverted the Theater, with the audience sitting on the stage facing the fixed audience seating in the house. The following plan gives an idea of the loudspeaker environment and the video gives an impression of the music played during the concert.

For the Akousma concert in 2014, dozens of loudspeakers were placed throughout the building’s lobby and along the public hallways spanning six floors. The audience and performers were seated at the top lobby level, facing the Concert Hall exterior extending down the hill. The musicians placed and moved the piece’s pre-produced tracks in real-time through the building, creating an all-encompassing auditory stage.

Francisco López was commissioned in the fall of 2011 to develop a new work for the EMPAC Concert Hall. Hyper-Rainforest was composed for 80+ loudspeakers placed around and above a platform for the audience. Once the audience was seated, they put on blindfolds and were transported to a sonic hyper-reality of sounds and music.

The following video is a time-lapse video of the installation in the Concert Hall, in which the composer developed and performed the work.

Pauline Oliveros (1932–2016) was an American composer, accordionist, and a central figure in the development of post-war experimental and electronic music. She joined the faculty of Rensselaer Polytechnic Institute in 2001 and worked at EMPAC on several of her music and research projects.

In honor of her 80th birthday in 2012, a special concert was developed for in the Concert Hall featuring the Deep Listening Band with Pauline, Stuart Dempster, and David Gemper. In 1988, the Deep Listening Band recorded a seminal album in the Fort Worden Cistern, Washington State — a two-million-gallon underground water tank with 45 seconds of reverberation. Jonas Braasch, professor at Rensselaer and a long-time collaborator with Pauline, developed a simulation of the acoustics of the cistern. By placing loudspeakers above the fabric ceiling of the Concert Hall and around the audience, the acoustics of the cistern were recreated for the live performance of the musicians.

The following video is an excerpt from the concert on May 10, 2012.
Watch and listen to the full concert.

Amacher was not able to finish the piece. Sergei Tcherepnin and Micah Silver, who worked closely with her on the project over the course of her residencies, collaborated on an interpretation of this unfinished work with the hope of sharing a glimpse of what this work was to become.

Their rendering was performed in October 2010 in the Theater using the wealth of audio material Maryanne had created in her development of the work, along with the loudspeaker configuration she so carefully documented during her residencies.

The following video is a recording of the performance at full length (25 minutes). It is more for listening than for watching.

The volume of the piece has a wide range, from barely audible to extremely loud. Certainly, this mix to just two channels can only give a slight impression of the full spatial rendering of sound, an element that is central to Maryanne Amacher's music.