EMPAC has developed complex, large-scale tools for composers, researchers, and audiences to develop and experience spatial audio at a extremely high level of refinement, whether for music, film, live performance, or gaming. Traditional methods of sound spatialization using loudspeakers — for example stereo, left-center-right, quadrophonic, and surround sound — are complemented with very large ambisonic and wave field synthesis (WFS) systems. These systems deepen listener immersion dramatically compared to traditional methods.
Concert Hall, Francisco López, Hyper-Rainforest. (2011) by Brian ChichesterEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
From the start of planning and designing EMPAC in 2001, the acoustics and technical infrastructure were developed to enable “any sound from anywhere.” An almost arbitrary number of loudspeakers can be placed anywhere in the volume of each space, but the Concert Hall is particularly exceptional; it is most likely the first large hall specifically designed to integrate the staging of acoustic instruments and ensembles throughout the hall, around and among the audience, with loudspeakers suspended above, around, and sometimes below.
Spatial audio has always been a focus of EMPAC’s media mission, conceiving and constructing several specific sound systems for research, production, and presentation. The main venues and studios have very few pre-configured, permanently installed systems. Artists develop new pieces during residencies with loudspeakers configured and implemented specifically for their work.
Theater, Wave Field Synthesis Array flown over audience seating . (2017) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
EMPAC Theater, Wave Field Synthesis Array with hundreds of small loudspeakers suspended above the audience in AFTER by Andrew Schneider with sound design by Bobby McElver.
Studio 1, multi-channel audio workshop with Hans Tutschku (2011). (2011) by India LombardiEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
Studio 1, 2011 Multi-Channel Audio Workshop with Hans Tutschku.
Studio 2, configuration of the High-Resolution Modular Loudspeaker Array for Wave Field Synthesis (2016) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
Studio 2, Wave Field Synthesis Array flown in front of the walls.
Venue specifications (2013)EMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
All venues are built to the same level of quality, serving a myriad of "experimental media and performing arts" projects at the intersection of the digital domain and the human experience.
Dedicated networks connect between all venues, yet each space can operate as an "island" independent of the others. In order to guarantee quality of service for each media type and production team, audio, video, control, and communication systems are networked independently.
EMPAC Connectivity (2009)EMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
Each venue serves as its own production and presentation island, independent from the others, but it can also be connected to any other space in the building. “Audio Video Panels,” are installed throughout each venue with its dedicated machine room, covering the whole studio including grids and catwalks, and in all residency studios, offices, and public spaces. Each panel allow access to the different fiber optic and electric network matrices that provide different services. A central machine room with associated video and audio production studios form the hub of the building.
Audio and video block diagram. (2008)EMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
Technology changes fast. This block diagram for the audio and video infrastructure, from EMPAC’s opening in 2008, can already be seen as a "historical document". At the same time, its potential has still not been tested to its limits.
Audio and Video Central Machine Room (2020) by Michael ValiquetteEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
EMPAC’s central machine room for audio and video routing and processing.
Audio Production Room (2020) by Michael ValiquetteEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
The central audio production room can be connected to any venue or studio, while each space can serve also as its own independent production environment. This space has manifold configurations for monitoring and producing spatial sound, including a 4th-order ambisonic array consisting of 25 full-range speakers and two subwoofers.
The walls are covered with absorptive panels, which are identical to those used in Studio 1. To add diffusion, they can be angled and positioned at different distances to the wall.
For full view of the room, please click the information button in the top left corner.
Studio 1, High-order ambisonic system. (2019) by Michael ValiquetteEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
Studio 1 is the only venue with a "currently permanent" loudspeaker installation. The 5th-order ambisonic array consists of 37 full-range speakers and four subwoofers positioned along the walls and across the ceiling.
Additional or different loudspeaker configurations are setup as required or desired for a residency or performance.
Click on the information button in the top left corner to see the whole space.
Studio 1, panoramic screen with acoustical transparent screen. (2012) by Johannes GoebelEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
The EMPAC 360-degree panoramic screen is based on the development by Jeffrey Shaw who helped with the design and production. This first major development of EMPAC’s started in 2003 with the design of a micro-perforated acoustical transparent screen, so loudspeakers could be placed behind the screen with sound entering the screen interior without obstruction.
The first interactive film for this screen was the EMPAC-commissioned THERE IS STILL TIME..BROTHER by The Wooster Group.
Panoramic screen, dimensions (2012) by Johannes GoebelEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
Three rings with a total of 32 loudspeakers are placed behind the screen, allowing localization of sound across the screen area. This solves the issue of "where to put loudspeakers" in immersive projections.
Panoramic screen (2008) by Eric AmeresEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
Panorama screen, viewed from above.
Studio 2, performance by Laura Luna inside the panoramic screen. (2017) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
Multimedia performance by Laura Luna created for the panoramic screen in 2017.
Concert Hall with ambisonic and Wave Field system on stage. (2017) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
An 8th-order ambisonic array consisting of 64 full-range channels and four subwoofers can be installed in the Concert Hall.
Additionally, a linear array of the EMPAC Modular Wave Field Array is positioned on the stage.
Concert Hall with ambisonic and Wave Field system. (2019) by Mick BelloEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
In addition to the 68-speaker ambisonic array surrounding the audience, two rows of the Wave Field Synthesis Array are installed overhead for the film screening of Sanctuary by Carlos Casas with music performed live by Chris Watson and Tony Myatt. With this wave field system, sounds can be focused directly above the heads of audience members.
Performance of Olga Neuwirth, Lost Highway Suite with the International Contemporary Ensemble. (2018) by Paula CourtEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
Performance of Olga Neuwirth’s Lost Highway Suite (2018), by the International Contemporary Ensemble, with live electronics and an ambisonic loudspeaker dome around the audience. The following drawings show the speaker placements in the Concert Hall.
Concert Hall, ambisonic loudspeakers, floor plan. (2018) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
Ambisonics” is a method of three-dimensional sound projection, used in the playback of recordings in ambisonic format or for placing amplified or electronic sounds live around listeners.
The ambisonic audio system consists of multiple loudspeakers deliberately positioned around an area. When controlled by a computer, the speakers in an ambisonic array project a sound to a specific location on a virtual sphere around the center of the array using a set of mathematical functions called spherical harmonics. The higher the "order" of ambisonics (a figure dictated by the number of speakers used in the system), the greater the spatial fidelity, making localization of sound in space more precise and easier to localize.
Moving sound in an ambisonic system occurs on all three planes—x,y, and z, or azimuth, elevation, and distance —resulting in a highly-refined and immersive listening experience.
Concert Hall, ambisonic loudspeakers, ceiling plan. (2018) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
High-Resolution Modular Loudspeaker Array for Wave Field Synthesis. (2016) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
Wave Field Synthesis (WFS) is a spatial audio rendering technique that places virtual sound sources in real space. The synthesis is precise and physically correct. One cannot distinguish the synthesized source from a "real" wavefield. With a WFS sourced sound, a human’s listening experience would be consistent with a similar naturally occurring sound, allowing listeners to be anywhere in the active sound field and still perceive the virtual sound source’s proper placement in space.
High-Resolution Modular Loudspeaker Array for Wave Field Synthesis. (2016) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
The EMPAC High-Resolution Modular Wave Field Synthesis Array is a 558-channel discrete loudspeaker array designed to take advantage of the added sound-stage dimensionality made available through the use of wave field synthesis (WFS). EMPAC embarked on the design and construction of this high-density loudspeaker array with the goal of increasing the accuracy in sound localization of traditional horizontal WFS systems while creating a modular, easily deployable, and accessible solution for composition, research, and presentation.
High-Resolution Modular Loudspeaker Array for Wave Field Synthesis. (2017) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
The Wave Field Synthesis Array was developed, built and brought to the world by:
Todd Vos, Lead Audio Engineer
in collaboration with:
Jeff Svatek, Audio Engineer
the EMPAC State Technology Team
Argeo Ascani, Music Curator
Johannes Goebel, Director
A paper describing motivation, implementation, and surprising results was presented at the 23rd International Congress on Acoustics, 2019: Johannes Goebel, The EMPAC High-resolution Modular Loudspeaker Array for Wave Field Synthesis
High-Resolution Modular Loudspeaker Array for Wave Field Synthesis. (2017) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
Wave Field Synthesis Array on the stage of the Concert Hall.
Wave Field Synthesis System array (2017) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
In the Theater, a performance of After by Andrew Schneider with sound design by Bobby McElver. The Wave Field Synthesis array is flown in two rows above the audience; it enables to move sounds down to just above the heads of the audience, moving row by row.
High-Resolution Modular Loudspeaker Array for Wave Field Synthesis. (2016) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
The Wave Field Synthesis array configured in a circle, flown from trusses in Studio 1.
Wave Field System array (2016) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
Markus Noisternig with audio engineer Jeff Svatek in circular Wave Field Synthesis array.
High-Resolution Modular Loudspeaker Array for Wave Field Synthesis. (2019) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
Next generation EMPAC High-Resolution Wave Field Synthesis Array, halving the distance between loudspeakers, which proofs to yield an audibly much more precise spatial focus when spatializing sound sources.
Summer audio workshop (2017) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
Between 2011 and 2019, EMPAC offered four summer spatial audio seminars and workshops in partnership with IRCAM (Institut de Recherche et Coordination Acoustique/Musique, Paris), HUSEAC (Harvard University Studio for Electroacoustic Composition), and CCRMA (Center for Computer Research in Music and Acoustics, Stanford University).
Summer audio workshop (2017) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
The extended workshops presented lectures, concerts, and demos allowing participants hands-on opportunities to explore systems designed to deliver detailed 3D audio using WFS, Ambisonic, Binaural, and Transaural audio techniques.
Summer audio workshop (2017) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
Summer audio workshop (2019) by EMPACEMPAC — The Curtis R. Priem Experimental Media and Performing Arts Center at Rensselaer Polytechnic Institute
The EMPAC audio production team (2021)
Todd Voss
Jeffrey Svatek
Stephen McLaughlin
Development, Engineering, Construction, Programming, Recording, Editing, Mastering, Residency Support ...