Jbl 2485 j brochure

Page 1

PROFESSIONAL SERIES

FEATURES:

120 \Vatts continuous program above 300 Hz

100 mm (4 in) edgewound aluminum ribbon
Voice coil

100 mm (4 in) phenolic diaphragm

4) mm (2 in) horn throat diameter

COMPRESSION
DRIVER

Model 2485] is an extremely highipower profesr
sionaliquality compression driver It has a 100 mm
(4 in) voice coil and a magnetic structure weighing
10.5 kg (23 lb). It can take the most explosive trani
sients in stride and reproduce them at thunderous
leVels. Model 2485] is built to typical jBL standards
of precision.

Diaphragms of phenolic impregnated linen are
Virtually indestructible. After manufacture, each
driver is tested for conformity to rigid performance
standards.

The driver features a waterproof rear cover for
the mounting of a line matching transformer in
outdoor applications. A waterproof gland nut allows
cable connections to be made while maintaining
moisture isolation integrity.

Page 2

n L A:-
JILX"
GIU]

Model 2485} is unequalled by any other driver in
both power capacity and efficiency. It can be used
as the high frequency section of twoeway systems
for highepower reinforcing applications or by itself
with a 300 Hz highepass filter for voice paging or
reinforcing systems of high quality and powerr

ARCHITECTURAL SPECIFICATIONS:

SPECIFICATIONS:

Throat Diameter, 49 mm (zinl
Nominal Impedance: loo
llinimum Impedance: 12 J ((9 3 kHz

DC Resistance: .5 Q t 10,0 (4L) 25 C
lJoivei- (.apaeiogi l 0 continuous program above 01] Hz

bensiuvity: 111 dB i lL, l (9 1 m oneaxis on horn
118 dB SPL, 1m\i on planeAvave tnhe

Nominal eaieieriev: with (son Hz to 23 kHz)
Frequency Rangc: 300 Hz to o Lllz

Recommended (irossox er: .500 Hz or higher, 11 dB octave minimum

The compression driver shall consist of a ierrite magnetic structure with all mag
netie assemhlv parts machined from east or extnidcd hillet stock. The phasing plug
shall he assemhled of concentric horns to minimize phase cancdlaLions, and it shall
lie coupled to a tapered throat. The diaphragm shall he phenoliceimpregnated linen
for high durahiliti 'I he voice coil shall he edgewotind aluminum rihhon of not less
than 100 mm (4 in) in diameter, operaLing in a magnetic field of not less than 1.9 tesla
(19.000 gausslr The driver shall he fitted with a waterproof rear cover suitable for the
internal mounting of a line matching transformer, and waterproof gland nut for cable
connections

Performance specifications of a tvpical production unit shall he as follows,
Measured sensitiv' ' with a 1 mW input on a 25 mm (1 in) terminated tuhe. averang
from 500 ll; to 2.5 kllz. shall he at least 118 dB SPL. Measured sensi 4' with a I \Y
input at I m distance on axis from the mouth of a horn with a Q of 63 a\ eraged in
the 2 Lllz octave hand shall he at least 111 dB SPL. As an indication ofelectromee
chanical com' sion efficiency, the BI factor shall he at least 19 newtons per ampere.
Frequencv response, measured on a terminated tube. shall he flat within i 5 dB
from 300 Hz to 5.5 Lily. Nominal impedance shall he 16 ohms and power capacity
shall lie at least 120 watts normal speech or miisie program material

The compression drn er shall he the .lBL Model 248-3]. Other drivers will he cone
sidered for equivalency provided that submitted data from a recognized inde
pendent test lahoraton' verifv that the above performance specifications are met

120

SPL 180: 20a Pa}
2 3

8
impedance Ohms

A ' ~316
10!) non 50¢ woo 2m: 5000 «me man

Frequency in Hz

Response on JBL 2366 Constant Coverage BieRadial Hornr
Frequency response of the 2485} coupled to aJBL 2366
Constant Coverage BieRadial horn, measured oneaxis at a
distance ofI meter with a lewatt (4.0 V RiVIS) input in a
reflectionefree environment, with impedance vs frequency
curve A horn with a pure exponential flare, such as typical
radial horn designs, will exhibit greater high frequency output
oneaxis at the expense of lost angular coverage

UBL

jBL Professional, 8500 Balhoa Boulevard, PD. Box 2200, Northridge,

Diaphragm: .23 mm 10.009 in) phenolic

Voice Coil Diameter: 100mm (4 in)

Voice Coil Material: Edgewound aluminium rihhon

Flua Densiti" 1.9 '1 (19,000 gaiiss)

California 91329 If.S.A. "/89 10.

B1 Factor: 19 .\I/:\
Positive voltage to black terminal gives diaphragm motion toward the phasin plm

Dimensions: 235 mm 911 in) diameter
330 mm 13 in) depth

Mounting Four l/azo threaded holes, 90° apart
on 101.5 mm (4 in) diameter

Weight 13.8 Lg (sol/a lit)
gilt: 145kg(321h)

Ciiritinuous program it detioeel as 3 dB giLiiiLr rliao eontioiioiis pint noise» and it a
eorisi-riariie r\prt..ioo oi the rran.diiteit alriiii, to handle» normal speech and

Shipping w

rniitie priigiiim rniireiiai (zonrioiioos pinh mnsc poner iAtlngs are- lured nith pinle
nooe iiipiii liming . o till ere.r iaeroi iiiiii a high pass tilrei set at rhe speeiiieei
lowei limiting tradiienei ior tivo hours iiiiiaoon

1sentiriiiri ioeiitiiied vith l \t inpiit at i m tiisrariee on avs irom the month oi a
both arm a Q ot os nitramti in the 2 Hi; oerave h d

l.\t tpetiiied hi reeopoilerl slaindards Urg'AiH/uriims, serisitiviti it roeasiireti \ch the
eiiiier eonpltd to a itriiiiriited tube The- JBI. .entiriiiti lining rtprusunls rhe- 51].
in a 2s mm [1 m7 [Clnlin er riiiie, using a i row iiipiii signal (it izri v into lofli
snepr iiom suit 11/ to 2: MIL The Sunsilniq tarinii him a i \i inpar voiilei he

in til; grtalcr

tw
in 12
no in
3
§
g in mi 316
e
a
110 W

.. __ in
2a 5a m m sea «m 2mm mm mm ammo

Response on PlaneeWave Terminated Tuber Frequency
response and impedance modulus of Model 2485] coupled
to a 49 mm (2 in) diameter terminated planeewave tube, with
sensitivity referenced to a 25 mm (1 in) tube. This is the
power response of the transducer, and is the frequency
response that will he obtained on a true fullerange constant
directivity horn design, such as JBL s 2361) series of Constant
Coverage BieRadial Hornsr

lal. eonrmiialli eiipigm in rcsLiiich ii-lareti to proeiiier impioii-nii-nr he nliutuills piodaerion
iotthotit, and design rei'ioeioeins are iinrotiiieeei into LMumg piotiiito iviriioiir noriee at a
routine etprestioii or that pliilotopln ior this reimm ani eorrent jBl. proeiiier mai diiter in
some re.peet tiom it~ piihloheti (ILerlptiun. hiir \Hll aluiiis etioal oi i-tee-eei the original
design speeiiiearions iiniets otlieriiitt ~mieii

$52488 Printed in i's.\