Jvc Zero9 Service Manual

Page 1

SERVICE MANUAL

MODEL

ZERO-9

SPEAKER SYSTEM

No. 2489
JUNE 1979

Page 2

1. Specifications

Type
Speakers

t 3-Way, 4-speaker bass reflex

: 12 (30 cm) x 2 free edge woofer
4-1/2" (10 cm) metal dome 8:
cone construction type midrange
Dynaflat ribbon type tweeter

Power handling : 150 W RMS (DIN)

capacity 300 W (MUSIC)
Frequency response : 25 -- 50 000 Hz
Impedance : 6 Q

2. Removal Procedures
2-(1 ) Attenuater

Pull off the knob and remove the hexagonal nut retaining
the attenuater by using a pair of needle-nosed pliers
or a box wrench. When the knob is excessively tight, wrap
it with a piece of thick tape or a strip of rubber and then
grasp with a pair of pliers.

7 Nut
7/
a, . Washer
Knob C Attenuater
. a
Control Panel {n.1, j Buifle Board
Fig. 1

2-(2) Removal and attachment
of the speaker units

Loosen the screws with a 5-mm hexagonal wrench. Vinyl
tubes are employed as spacers for the midrange speaker
and tweeter. When these speaker units are replaced, also
replace the spacers together with them.

2-(3) Removal and attachment of
the speaker protector

When removing the speaker protector, insert a small
pointed object into a hole at the rim of the protector and
pull toward you. Pull the protector at several equidistant
points along its outer edge in this same way. When attach-
ing the protector, apply a slight amount of adhesive into
the six slots of the equalizer and then push the protector
in its place.

ZERO-9
No. 2489

: 92 dB/W, m

: 450 Hz, 5500 Hz

:0, -l, -2, -3, -4, -6 (d8)
constant resistance

Saund pressure
Crossover frequency
Level control

Dimensions : 41-5/16"(H) x 16-1/8(W) x
16-3/16"(Dl
(104.8 x 40.8 x 41.0 cm)
Weight 92.6 lbs (42 kg)

2-(4) Removal of the dividing network

Loosen the six screws on the back panel and the single
screw below the back panel (181 mm below the center
of the back panel). Then the back panel can be taken off.

Network board

Dir 11:1 (HI-1 (3 r

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fwfibvnl in /%"J . i V
Il~$:'.'.l i (hit // J . '
ll, w
, -~ -._ 3

(

Wood screw
(12 mm) x 6

(32 mm) x 1
2-(5) INPUT terminals

Before installing the terminal knob into the back panel, turn
the terminal knob until a few of its threads on the stem
remain exposed to receive the nut as illustrated in Fig. 3.

Nut
9
Threads should 9 .7 Terminal
remain here. . ' .7
/ _//¢._,)
0 X vi :3;
d
,1
l l '~ .
5 Q 3..-"...7 '7_.-""V
( I" M 6) .- Red for
£9 (+) terminal
Fi . 2 L (3" 'Washer
ll Black for / l
(4 terminal @
. lg"
| \1
% we -- Knob
Fig. 3