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58 Live Sound International   

January  2005

owed seating areas under the balcony.

The DSA concept, the brainchild of

EAW’s Dave Gunness, is fairly simple to

explain and implement, but that sim-

plicity belies a lot of sophisticated

design work. (For more about the DSA

Series, see “Designer Notebook” in the

October 2003 issue of 

Live Sound.

)

The powered DSA enclosures, sim-

ilar in look and shape to classic “col-

umn loudspeakers,” incorporate elab-

orate digital signal processing (DSP)

that allows their output to be tightly

focused on the audience, and kept off

of surrounding surfaces. This cuts

reverberation, resulting in cleaner, less

cluttered and more direct sound – a

particular challenge in more reverber-

ant worship spaces.

OFFSET “LINES”

Specifically, the model DSA250 loud-

speakers used on this project include

eight 4-inch cone drivers in an offset

“line” configuration that minimizes

the height of the enclosure. The high-

frequency section is made up of eight

1-inch soft-dome tweeters integrated

with a shallow multi-cell horn

designed to keep the acoustic centers

as close as possible. Both component

configurations are designed to opti-

mize the onboard DSP control.

Zandstra was already familiar with

the DSA concept. He had implement-

ed it’s “grandfather” technology –

found in the large-format KF900 Series

loudspeakers – as the basis for a high-

output system at Spartan Stadium, an

80,000-seat open-air stadium at

Michigan State University.

“Obviously these are vastly different

projects in terms of scale and objec-

tives,” Zandstra points out. “However,

the concept, in general, is scalable, par-

ticularly in this newer DSA iteration

used at Haven. Another aspect of this

design, and one that frequency comes

up with church systems, is to minimize

the aesthetic impact of the loudspeak-

ers. The thin profile of these boxes

played into that need.”

While the previous system had uti-

lized a mono central cluster design,

the sound team wanted to try a stereo

setup that would help “open up”

musical programming, giving it added

spatial imaging. For the demo,

Zandstra brought in Genie lifts and

flew single DSA250 boxes left and

right at the front platform. Following

the sound team evaluation, he invited

church leadership to sit in for a listen.

“We were concerned about attain-

ing sufficient spoken word intelligibil-

ity with the left-right design, but the

demo proved that this could be

achieved,” Zandstra says. “The bonus

to their ears was the rather large audio

image the system put into the room.”

Once this direction was endorsed,

the Parkway install team, which also

includes electricians, got busy running

the additional cabling and AC power

“drops” needed for the new system.

Church staff also proved helpful with

handling some of these system infra-

structure issues, including setting up

additional patch panels and patch

“pockets” on stage.

Following removal of the existing

center cluster, the new loudspeakers

were flown left and right about 20 feet

above the front platform via load-rated

aircraft cable attached to certified beam

structures above the ceiling. DSA Pilot

software, loaded on a PC at the house

mix position linked to the loudspeak-

ers via RS-485, provides optimized DSP

parameters, tailored by the user.

The DSA250 loudspeakers offer a

fixed 120-degree horizontal coverage

pattern and, with the DSP, the vertical

beamwidth can be established any-

where from 15 degrees to 120 degrees.

Coverage is supplied side-to-side

across the room’s approximate 50-foot

width, with the output of the loud-

speakers divided at the center aisle. 

In addition, coverage extends to

To the left, one of the underbalcony loudspeak-
ers serving shadowed regions, and above, a
rear view of one of the DSA250 mains.

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