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Installation
Loosen the gland nut in the side of the driver housing enough to admit the
loudspeaker wire/cable. Alternately, a 1/2-inch conduit fitting can be
substituted for the gland nut. However, the sealing washer must be retained.
The Uni-Lok swivel mount allows the speaker to be precisely positioned
and locked in place. A mounting plate is furnished with the Uni-Lok but
Y2-inch pipe may be used instead.
To flush mount the horn, finish drilling the four predrilled holes from the rear
four corners and insert #8 machine screw toggle bolts or screws to secure
the unit from the front.
A foam insert (CFID32F) is available to screen against nesting birds and
insects.
Polar Response
The directional characteristics of the CFID32 were measured by running a
set of horizontal/vertical polar responses, in Electro-Voice's large anechoic
chamber, at each one-third-octave center frequency. The test signal was
one-third-octave pseudo-random pink noise centered at the indicated
frequencies. The measurement microphone was placed 6.1 m (20 ft.) from
the horn mouth, while rotation was about the waveguide geometric apexes.
These axes of rotation are quite close to the apparent (acoustic) apexes
across the frequency range of measurement. Errors attributable to the slight
differences between the geometric and acoustic apexes are reduced to an
inconsequential level by the relatively long, 20-foot measuring distance.
The horn was suspended freely with no baffle. The polar plots shown in
Figure 1 display the results of these tests. The center frequency is noted on
Figure 1
CFID32 Polar Response
www.electrovoice.com • Telex Communications, Inc. • www.telex.com
© Telex Communications, Inc. 02/2001
Part Number 38109-841 Rev A
each plot. The wider plot on each chart is the horizontal polar (-) and the
narrower plot is the vertical polar.
Beamwidth
A plot of the CFID32's 6 dB-down total included beamwidth angle is shown
in Figure 2 for each one-third-octave center frequency.
Frequency Response
Figure 3 shows the axial frequency response of the CFID32. It was measured
at a distance of 1 meter, using a swept sine wave.
Transformer
A transformer and power selector switch are installed in the rear housing.
The level of the CFID32T may be adjusted by moving the switch setting;
clockwise increases the power.
Low-Frequency Driver Protection
When frequencies below the low-frequency cutoff for the horn assembly
are fed to the driver, excessive current may be drawn by the driver. For
protection of driver, amplifier, and transformer (if driver with built-in
transformer is used), capacitor(s) in series with driver, or transformer primary
are recommended. Table 1 (below) indicates recommended values. The
values shown are for 200 Hz. Values for other frequencies can be determined
by using the formula:
[
C
x 200
C =
200
f
Table 1. Series Protection Capacitors for 200 Hz and Below
.
P
o
w
r e
I
m
3
2
W
1
5
W
1
0
W
5
W
2
5 .
W
1
2 .
5
W
Figure 2
CFID32 Beamwidth vs. Frequency
]
C
= Values shown in the following table
200
f = New Frequency
7
0
V -
o
t l
L
n i
e
s
p
e
d
a
n
c
e
C
a
p
a
i c
a t
n
c
e
I
m
1
6
1
5
m
f
3
3
5
2
m
f
5
0
0
1
3 .
m
f
1
0
0
0
0
7 .
m
f
m
f
2
0
0
0
0
4 .
4
0
0
0
0
2 .
m
f
CFID32 Frequency Response
(1 watt at 1 meter)
2
5
V -
o
t l
L
n i
e
s
p
e
d
a
n
c
e
C
a
p
a
i c
a t
n
c
e
2
0
4
0
m
f
4
2
2
0
m
f
6
3
1
3
m
f
1
2
5
7
m
f
m
f
2
5
0
4
5
0
0
2
m
f
Figure 3
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