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Meeting held June 23, 2004, at Pacific Northwest Theater Associates (PNTA), Seattle, WA
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Meeting held June 23, 2004, at Pacific Northwest Theater Associates (PNTA), Seattle, WA
Photos by Gary Louie, Secretary, PNWAES
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The PNW Section held its annual business meeting June 23, 2004 and presented
Dave Gunness of Eastern Acoustic Works on their digitally steerable line array
loudspeaker systems. About 37 people attended the meeting, which was held in
the theater demo space of Pacific Northwest Theater Associates in Seattle. As
is our custom, everyone at the meeting briefly introduced themselves.
Then the annual election was held. As per bylaw procedures, a slate of candidates was presented the previous month. A quorum was established (18 members), and ballots distributed. The 2004-05 PNW officers will be:
AES Western Region Vice President Bob Moses then presented AES Certificates of Appreciation from the Board of Governors to Rick Chinn, Gary Louie and Dan Mortensen, for long standing service to the vitality of the Section. Next, Dave Gunness began his presentation on steerable arrays. After graduating from the University of Wisconsin in 1984, Dave spent 11 years with Electro-Voice, before joining Eastern Acoustic Works in 1995. He spent his first year with EAW establishing a custom product design system; then undertook the development of the KF900 Series speaker system, as well as its Phased Point Source Technology (PPST) beam-forming technique - technologies which have been incorporated into the recently released DSA-Series digitally steerable arrays. He has designed over 100 unique horns and several-dozen speaker systems for EAW (among them: MH433, BH822, MQ series, LA400, etc.), holds six patents, and currently serves as EAW's Director of Research and Development. He is a member of the Audio Engineering Society. Dave described most other electronically steered speaker arrays as voice range with limited high frequency response. EAW wanted to provide wide steering and response well above 8 kHz. He showed slides of early experiments on large array systems in the late nineties, which were "barely there" in terms of the digital signal processing required. Their research led them to a palette of known techniques to achieve their goal for the DSA series - wide range, easy steering and feasible system construction and appearance. This is not a touring system, but a small column format. Dave showed impulse plots that showed how to integrate the multiple drivers into an approximation of a steered point source. 8 staggered 4 inch LF drivers, and 8 stacked 1 inch soft dome HF drivers in a shallow multicell horn comprise the column, making it smaller than you might think. It was also more expensive than you might think, until you realize that the housing includes 16 power amplifiers and 16 channels of DSP, with attendent EQ, limiting, delays, and speaker protection. A comprehensive software package manages the arrays, and communicates with the columns through an ethernet-type cable. Thus, AC mains, audio, and a network cable are run to each installed system. A LF only version of the column was presented along with the standard product, and for this demonstration, the columns were laid horizontally on a table to facilitate attendees examination of the steering. Many polar plot slides were shown. After a break for light refreshments, the door prize drawing was held, with the following winners:
Reported by Gary Louie, PNW Section Secretary |
