The following will be a general overview and design of the Stanford Laptop Orchestra (SLOrk) speaker.  The SLOrk speaker was designed and built in the winter of 2008 led by myself with over twenty doctoral, masters, and undergrad students for an independent study course on taught by Prof. Ge Wang. The speaker consists of a custom built six-channel hemispherical design using six discrete car audio speakers, six onboard amplifiers, and a hemispherical wooden enclosure.  The speaker has a single ON/OFF switch, can connect to any multichannel audio interface using six mono TS audio jacks, and requires a single 12V DC power supply.

The overall design goal of the speaker was to provide an acoustical "point source" immediately adjacent to a performer.  This concept strongly couples a single laptop performer with his/her own localizable sound in an effort to more closely emulate typical acoustical instruments found within a standard orchestral ensemble.  Within the context of a larger ensemble, this proves vital and allows a large number laptop performers to more cohesively play, rehearse, listen, and make music together, just as any other traditional ensemble.  As opposed to using a central mixing console, summing multiple laptop inputs to stereo or surround output, and displacing the sound from the performer, the audience and performers are able to discern who is making what sound, greatly increasing the aesthetics of the laptop orchestra musical experience.  Great inspiration and insight was taken from the Princeton Laptop Orchestra (PLOrk) throughout the design and construction process.  Please see http://plork.cs.princeton.edu/.

To effectively simulate such an acoustic point source, an unusual enclosure shape and atypically large number of discrete speaker channels were necessary. For ease of use and design, a hemispherical enclosure was chosen for this purpose.  Within the hemispherical enclosure, five speakers are placed around the 360 periphery and one directly on top. Before the final design of the hemispherical speaker array was chosen, other such enclosures allowing similar control, including spherical and tetrahedral, were discarded.  Spherical enclosures require some form of additional mounting stand to keep the speaker steady and tetrahedral enclosures are considerably more difficult to build and move around. 

Additionally, a small, light weight speaker arrays with simple interconnections were required for ease of setup and greater mobility.  Consequently, considerably small audio amplifiers were necessary to be housed within a relatively small enclosure with minimal additional hardware.  Particularly for day-to-day rehearsals and concerts, this mobility and ease of setup requirement is critical and was greatly taken into account throughout the design process. 

As mentioned above, over twenty students graciously dedicated much of their winter quarter to construct twenty of the SLOrk speakers just in time for the start of the new ensemble.  On behalf of the Stanford Laptop Orchestra, we must thank: Professor Ge Wang, Diana Siwiak, Reed Anderson, Steinunn Arnardottir, Brett Ascarelli, Mark Branscom, Hayden Bursk, Baek San Chang, Jeff Cooper, Luke Dahl, Lawrence Fyfe, Gina Gu, Ethan Hartman, Yungshen Hsiao, Turner Kirk, Adnan Marquez-Borbon, Jieun Oh, Jason Riggs, Kyle Spratt, Hiroko Terasawa, Cobi van Tonder, Chris Warren, Carr Wilkerson, Sasha Leitman, David Bao, Juhan Nam, and many others.



Nicholas J. Bryan
Center for computer Research in music and acoustics (CCRMA)
Stanford university, California USA