Quiver Locative Audio (2010)

The Quiver is a wearable audio system for listeners to explore how location dependent sound and music can alter the perception of a space.

It was created as part of an apprenticeship at Mark Bolas' Mixed Reality Lab (MxR) at the USC Institute for Creative Technologies. Building off of previous work on simulating hearing loss in virtual training environments, we explored psychophysics, signal processing, and location aware media experience design.

Using an aluminum and magnesium 3 inch diameter full range driver in a pipe enclosure, the Quiver features portability and omnidirectional sound directivity. Inside the enclosure is a "Class-D" audio amplifier and an Arduino microcontroller.

After testing with Arduino control of a miniature mp3 player (ARCHOS Key), we switched to using GPS and audio playback Arduino expansion boards to implement the location aware feature where the speaker uses its GPS coordinates to determine what sound file to play. Quiver has a carrying strap, recalling the culture of boomboxes and social practices and implications of altering sound in a public environment. It also relates to the DIY audio and Arduino, Raspberry Pi, and other single-board computer communities.

The acoustic design creates an "umbrella-like" immersive effect as a result of the omnidirectional sound, horizontally oriented driver, room reflections and interactions. The speaker underwent many iterations in driver selection and enclosure pipe length to achieve a more neutral frequency response given the design constraints of low-cost and portability.

By developing this combination of features, we explore the experience design of locative audio. For instance, we experimented with programming GPS change points for downtown Los Angeles that would trigger playback of different Steve Reich's compositions (such as Electric Counterpoint) as one brings the speaker from one location to another. This creates a shared (unlike isolating headphones) acoustical augmented reality where listeners explore the repetitive and ambient nature of navigation through a sleepless city, a flow-space of shifting frequencies and possibilities.

Speaker Specs:

Qtc: 0.69
Fc: 139 Hz
F3: 142 Hz

Skills and Technologies Employed:

self-directed exploration and participation with the DIY audio and electronics communities, amplifier design, signal processing, microcontroller programming, acoustics and transducers, industrial design, physical craft with hand and power tools