Page 1
PROFESSIONAL SERIES
FEATURES:
Uniform horizontal on and off axis frequency
response
Precise horizontal and vertical pattern control
Full horn loading to 500 Hz
Flat front and compact size
Lightweight construction
49 mm (2 in) throat entry
The JBL 2385A Bi-Radial horn¹ is designed
for flush cabinet mounting or compact cluster applications. The 2385A has a nominal 60° horizontal
x 40° vertical pattern. The horn provides uniform
on and off axis frequency response from 500 Hz to
beyond 16 kHz in the horizontal plane and 2 kHz
to 16 kHz in the vertical plane with constant directivity above 2 kHz. The horns small vertical mouth
dimension (just slightly larger than the compression driver used to drive the horn) allows very
compact single and multiple horn/driver systems
to be put together Should vertical pattern control
be required below 2 kHz, two or more horns may
be stacked vertically to restore full Bi-Radial
performance.
Page 2
The exceptionally consistent horizontal dispersion eliminates the midrange narrowing and high
frequency beaming problems typically associated
with conventional horn designs. Additionally, the
highly predictable performance of the 2385A
greatly simplifies cluster design. The need for
horn overlapping is minimized and lobing and
comb filter effects are virtually eliminated.
Computer-aided design techniques were used
to derive the horn contours in the horizontal and
vertical planes. Utilizing sidewall contours based
on a polynomial power series formula, the horn
design yields smooth response, low distortion, and
SPECIFICATIONS:
Throw: Medium
Horizontal Coverage:
Angle Degrees (-6 dB):
Average Range:
Vertical Coverage:
Angle Degrees (-6 dB):
Average Range:
Directivity Factor (Q):
Directivity Index (Di): 12.8 dB (+2.0, -2.0)
Usable Low-Frequency Limit:
Minimum Recommended
Axial Pressure Sensitivity¹:
Average Range:
Crossover Frequency: 500 Hz
70 (+20, 15)
500 Hz 16 kHz
40 (+ 11, 11)
2 kHz 16 kHz
19.0 (+6. 7)
1 kHz 16 kHz
400 Hz
114 dB SPL. 1 W @ 1 m
even coverage. This design avoids the performance disadvantage of horns that feature sharp
flare transitions and flat sidewalls. The Bi-Radial
compound flare configuration provides constant
coverage over defined, solid angles. To ensure light
weight, superior strength, and freedom from resonances, the horn bell is constructed of molded
structural foam.
The 2385A will accept the 49 mm (2 in) diameter
throat 2446, 2450, or 2485 compression driver. With
the addition of the 2327 adapter, the horn will
also accept the 25 mm (1 in) throat 2426 driver.
US Patent No 4,308,932 Foreign patents pending
Construction:
Overall Dimensions:
Mouth Height: 279 mm [11 in]
Mouth Width: 445 mm [17.5 in]
Length. 236 mm [9.28 in]
Mounting Dimensions.
Baffle Cutout Required:
Measured on axis in the far field with I watt input (4 0 volts RMS. 16 ohms) and
referenced to I meter distance using the inverse square law Listed sound
pressures (SPL re 20 µPa) represent an average from 1 kHz to 4 kHz using the 2446,
2450 or 2485 driver
Rear Height:
Rear Width: 400 mm [15.75 in]
Height: 238 mm [9
Width: 403 mm [15
Net Weight: 2.2 kg [6 lb]
Shipping Weight. 4.6 kg [10 lb]
Molded structural foam (nominal 10 mm [0.38 in]
wall thickness)
235 mm [9.25 in]
[Front mounting only]
3/8
in]
7/8
in]
Beamwidth vs Frequency
Directivity vs Frequency
Page 3
Frontal Isobar Contours
500 Hz octave bandwidth constant sound pressure contours
of 0 to - 15 dB in steps of -3 dB. The contours are plotted on
polar grid lines with on axis being the center of the plot. The
data was gathered by taking an octave polar plot at all
oblique angles from 0° (horizontal) to 90° (vertical) in steps of
15°. Same test conditions as horizontal polar response.
1 kHz octave bandwidth constant sound pressure contours.
Same conditions as 500 Hz contours.
4 kHz octave bandwidth constant sound pressure contours.
Same conditions as 500 Hz contours.
2 kHz octave bandwidth constant sound pressure contours.
Same conditions as 500 Hz contours.
8 kHz octave bandwidth constant sound pressure contours.
Same conditions as 500 Hz contours.
Page 4
Harmonic distortion. Second and third harmonic distortion
curves of the 2385A with I watt (4.0 V RMS) and 10 watts (12.65
V RMS) applied to the JBL Model 2445 compression driver.
Measured on axis at a distance of 1 meter in a reflection-free
environment.
Frequency response and impedance. Frequency response of
the 2385A, measured on axis at a distance of 1 meter with 1
watt (4.0 V RMS) applied to a JBL Model 2445 compression
driver, in a reflection-free environment, with impedance vs.
frequency curve.
Horizontal off-axis response. Horizontal off-axis response taken at 15 degree intervals out to 60° off axis. Both
normalized (equalized flat on axis) and unequalized responses are shown.
Vertical off-axis response. Vertical off-axis response taken at 15° intervals out to 60° off axis. Both normalized
(equalized flat on axis) and unequalized responses are shown.
JBL continually engages in research related to product improvement New materials. production methods. and design refinements are introduced into existing products without notice as a routine
expression of that philosophy. For this reason, any current JBL product may differ in some respect from its published description, but will always equal or exceed the orginal design specifications unless
otherwise stated.
SS 2385A
JBL Professional, 8500 Balboa Boulevard, PO. Box 2200, Northridge, California 91329 U.S.A.
CRP 2M
12/95
Loading...