We’re back for round two of the Sound Research group. Our first meetup had great turnout of some of the field’s preeminent audio researchers and we expect that this one will be even better! The topic for this meetup is Ambisonics.
ambisonics [ˌæmbɪˈsɒnɪks] n.
Ambisonics is a surround sound system first developed in the 1970s. Its main difference from other surround techniques is that it separates transmission channels from speaker feeds, the speaker feeds being derived using a decoder situated in the living room. Decoders can be implemented in either hardware or software. Typically more speakers are used than transmission channels, and the more speakers used then the more stable the resulting soundfield. Speakers can be arranged in a number of configurations, regular polygons being the most popular.
Luckily there will be no shortage of experts in the house. Eric Benjamin of Dolby Labs will be presenting some of his research. Eric is the author of a multitude of papers pertaining to Ambisonics decoding, Ambisonic localization, tetrahedral microphone techniques, and configuration of irregular loudspeaker arrays. His work has opened the door for many sound artists interested in 3 dimensional sound and is largely recognized in the spatial audio community as being groundbreaking research.

Aside from Gray Area’s 8-channel speaker array, we will have a 2nd order Ambisonics system for listening experiments and demos. The sound system belongs to independent sound artist and Ambisonics enthusiast Elan Rosenman. Elan will discuss his experiences configuring his sound system.

This speaker array consists of 12 speakers mounted to 10’x10’x11’8.75” cubic steel frame. (The frame is extended higher to compensate for the loudspeaker offset). By placing a speaker at the center point of each 12 sections (facing the center at 45 degrees), a geometric relationship is created that meets the requirements for a “full-sphere” 2nd order ambisonic system. The frame is made out of 1.5 inch steel square tubing consisting of ~5‟ sections that are connected with larger diameter brackets and couplers. The pieces slide together and are secured with set screws. The speakers mount in the same fashion to the mid-point of each section.

Agenda

7:00pm – 7:30pm : Presentations
7:30pm – 8:00pm : Demos / Listening
8:00pm – 8:30pm : Discussion / Show and Tell