J.W. Davis SC SERIES User manual

The Mark of the Professional...
NEW TECHNOLOGY OLD RELIABILITY
J.W. Davis & Company •3030 Canton Street • P.O. Box 710219 • Dallas, Texas 75371-0219
Sales 800-527-5705 • Fax [phone] • Corp 214-651-7341 • Fax [phone] • [email protected] • www.jwd.com
INSTALLATION INSTRUCTIONS
SC SERIES SOUND COLUMNS
Sound columns (also known as line arrays) are speaker systems specifically engineered to meet
the special acoustical characteristics of installations that have highly reflective surfaces and/or
lowceilings. Inthesecircumstances,theobjectiveistoreducetheexcessivereverberationthatlimits
therequiredsound amplification being attained before acoustic feedbackisencountered.
The unique coverage pattern of the columnar speaker system, shown in the idealized drawing
below, reduces the undesired reverberation by concentrating the sound pressure in the listener’s
area and by attenuating the reflections produced from the more reflective ceiling and/or wall
surfaces. Therefore, correct placement and direction of the speakers are
critical for best performance.
In the typical installation, assuming that the room is rectangular shaped, a
single column should be placed in a center-
front location. If the microphone position is
on the long side of a rectangular room, two
columns should be used that arespaced
midway between the microphone position and the side walls.
The minimum height should be slightly above the head of any per-
son standing and speaking into a microphone (See Figure 2). The column should be tilted down-
ward so that the center of the column is aimed at a point approximately two-thirds of the distance
of the audience when seated. This allows the listeners who occupy the front rows to avoid exces-
sively loud sound while permitting listeners located in the rear to hear comfortably.
for
Figure1
SC-408
SC-100 SC-30
SC-70
090717171
Figure2

NEW TECHNOLOGY OLD RELIABILITY
J.W. Davis & Company •3030 Canton Street • P.O. Box 710219 • Dallas, Texas 75371-0219
Sales 800-527-5705 • Fax [phone] • Corp 214-651-7341 • Fax [phone] • [email protected] • www.jwd.com
The Mark of the Professional...
Mounting Suggestions
Basic mounting hardware is included with each sound column. The hardware for models SC-30,
SC-50, SC-70 and SC-100 consists of (1) hanging bracket for surface mounting and of
(2) a henge, chain and hooks to permit forward tilting (Figure 3) for more
precise beaming of the coverage pattern. If the column is being mounted in
a location that requires the cabinet to be swiveled sideways as well as tilted
to properly position the sound intensity, an optional mounting hardware kit
(model NSC-BR) shown in Figure 4 is available.
Transformer Installation
The impedance of each SC Series sound column is indicated in the table above. However,
transformers may be readily added in the cutouts located at the back of the cabinets except for
modelSC-408which requires internal installation. Note: If intendedto be used in 25Vor70V instal-
lationsatthetimeofpurchase,transformersmayhavebeeninstalledatthefactory. Therefore, the
impedanceofthecolumnsshouldbecheckedbefore applying power from the amplifier.
Model SC-408 hardware consists of a henge, chain and hooks to permit
forward tilting (Figure 3). Optional hardware kit (model SC-
BR) shown in Figure 5 is available if the cabinet must be swiv-
eled sideways for proper alignment.
The directional coverage patterns of sound columns require careful alignment. One technique is
to use a carpenter’s square to aim the “on-axis” beam to the desired location. Another widely
used technique is to use a mirror and flashlight. Regardless of the aiming technique, a sound
level meter should be used to verify the resulting coverage.
Figure3
Figure4
Figure5
Mounting hardware must be securely screwed into at least one wall stud
using screws or bolts rated with the loadbearing capacity of the hardware
supplied by the manufacturer.
Note: Sound columns, or other loudspeakers, should never be mounted
directly behind and near level with a microphone to avoid feedback.
Model Power
(watts) Impedance
(ohms) Coverage @ 1 KHz Sensitivity
(db @ 1wm) Speakers Size Shipping
Weight
Frequency
Range
SC-50
SC-70
SC-408
50
70
50
130-7,000 Hz
±5 dB
105-3,500 Hz
±5 dB
80-9,000 Hz
±5 dB
12
16
8
120° Horizontal
20° Vertical
120° Horizontal
20° Vertical
120° Horizontal
40° Vertical
99.7
102.0
98.2
Six 5”
(DS-505)
Eight 5”
(DS-505)
Four 8”
(DS-810)
7³⁄₄” W x 40³⁄₄” L x 5⁵⁄₈” D
7³⁄₄” W x 52³⁄₄” L x 5⁵⁄₈” D
11” W x 36¹⁄₄” L x 11¹⁄₄” D
33 lbs.
44 lbs.
48 lbs.
SC-30 30 120-13,000 Hz
±5 dB 8120° Horizontal
40° Vertical 98.5 Four 5”
(DS-505) 7³⁄₄” W x 28³⁄₄” L x 5⁵⁄₈” D 25 lbs.
SC-100 100 140-8,500 Hz
±5 dB 12 120° Horizontal
20° Vertical 97.3 Six 5”
(DS-510) 7³⁄₄” W x 40³⁄₄” L x 5⁵⁄₈” D 34 lbs.