The Threshold Studio in action

The Threshold Studio in action

How We Design

While acousticians are well trained in the technical vocabulary of sound, our clients and collaborators on the Design Team usually are not. Our work involves a deep knowledge of architecture and audio and video technology and a lot of math, but these are all means to an end. The conversation begins and ends with the subjective experience of our clients. We recognize our responsibility to avoid jargon and instead communicate in terms more accessible to those who don’t know our language. There are powerful, evocative parallels between sight and hearing: virtually everyone can understand the color black as perfect absorption, a diffuse reflection as a frosted mirror, or the randomness of sand rippled by wind or water.

 Particle burst animation of the Lyric Opera Chicago's new shell

Particle burst animation of the Lyric Opera Chicago's new shell

Beginning the design conversation on an intuitive, metaphorical basis establishes a way of conversing that is difficult to leave behind – it seems unfair to demonstrate progress by statistical presentation alone, and nuanced differences between design options don’t lend themselves to evaluation by means of comparative graphs. Conveying our ideas and recommendations at various points entails words, sketches, animations, and, at critical points, immersion in aural renderings of a room. These ‘auralizations’ are far more intuitive as a means of evaluation, relying upon the ear rather than presentation of statistics. Acoustically modeling a room or a series of rooms allows us to quickly and iteratively evaluate the effects of variations on room shaping, interior materials, and isolation approaches.

Studio in Use.jpg

In our studio, a sixteen-channel audio system and twelve-foot diagonal video screen immerse listeners in a strongly visual and compellingly aural experience that we have used to evaluate theatres, concert halls, lecture rooms, lobbies, and social spaces. Actors, singers, and musicians that we have recorded ourselves can be heard in these virtual rooms, compared to familiar benchmark spaces, and evaluated comparatively, by eye and ear together. An actor’s voice or a string quartet are far more accessible than charts and graphs. The experiential evaluation leads to insights that could not otherwise be reached, and many who enter the studio skeptical of their own ears emerge with a new appreciation of them.

Modeling and Analysis

Far beyond a means of presentation, modeling is a part of our day-to-day process. We embrace both physical and computer modeling, each of which has a place in design. In the early going, computer models of options and benchmark halls allow us to quickly evaluate the effects of differing audience arrangements on overall room volume and geometry. Modeling the benchmarks is as important as modeling the design options, translating listening experience in beloved halls into the virtual realm, thereby establishing a fair context for evaluation of the design options.

As early design progresses, comparative modeling helps us evaluate refinements in seating planes, interior materials, and isolation approaches – quickly and iteratively – allowing us to run alongside the Architect. This is the profound strength of digital modeling. Elements of still greater detail – balcony fronts and surface diffusion, for example – can benefit from finite element analysis, mathematical modeling capable of evaluating even extremely fine-scale shaping. We use finite element analysis in combination with genetic algorithms, a means of quickly evaluating thousands of potential shapes through a mathematical process inspired by natural selection in the biological world. The finalists are evaluated with full size mockups to which we listen, sometimes with a voice or a violin involved, correlating the measurements we take with the sound we hear.

AudioMapping.jpg

In the audio realm, modeling allows prediction of loudspeaker coverage and quantification of unwanted ‘spill’. The latter is as important to understand as the former, since spilled energy causes echoes and confusion indoors and irritates the neighbors outdoors. Mapping the energy onto wall surfaces in a room or onto the landscape and adjacent buildings for an outdoor venue help us select the most appropriate loudspeakers for the circumstances, often with the final evaluation of audio quality made by ear in front of the loudspeaker itself.

To the extent possible, the Client and Architect hear for themselves and participate fully in the decisions at hand. In this way, our projects benefit from different scales of evaluation, each of which informs those that come later. The moments of evaluation can be extremely powerful for everyone involved.