JDM A 4320 User manual

JDM®4 Zone Public Address Amplifiers
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Professional Four Zone
Desktop Mixing Amplifiers
A 4320 60W
A 4322 120W
Operating Instructions
Revision 02/10/12

Congratulations on purchasing this 4-Zone amplifier. It is housed
in a heavy duty 3RU rack mount cabinet and includes a host of
features. It provides an economical solution for smaller
installations including offices, workshops, smaller shopping
arcades, schools etc.
FEATURES
VERSATILE INPUTS
Channel 1 is a front panel mounted 6.35mm phone jack that
accepts either an unbalanced or balanced (tip / ring / sleeve)
microphone. Channels 2-3 comprise balanced XLR inputs via
the rear panel, with mic / line sensitivity adjustment provided, as
well as a switch to provide phantom power for condenser mic
inputs. Channel 4 has a switch to select between balanced XLR
or a pair of RCA line level inputs. Channel 5 comprises a pair of
RCA inputs, switch selectable between line or phono level.
TELEPHONE INPUT
A telephone paging and music-on-hold input connection is
provided via spring terminals on the rear panel. Music sources
can be from a choice of optional modules that are installed into
the front panel slot.
SLOT FOR OPTIONAL INPUT MODULES
A slot in the front panel is provided in order to fit one of the
following optional modules: A 4344A (TP-100RDS) AM/FM RDS
Radio tuner module, A 4346 (CDR-100RDSU) CD/tuner module
with USB.
PRIORITY MUTING
MIC 1, CHIME and SIREN have priority over other inputs. The
muting level can be adjusted via a knob on rear panel.
REMOTE CHIME AND SIREN
This is operated by buttons on the front panel which play various
tones across the speakers. When the spring terminal on the rear
panel is shorted, CHIME is activated.
FOUR ZONES SPEAKER SELECTOR
Any combination of mono speakers (4 or 8ohm) can be selected
via front panel selector switches.
PRE OUT
A preamp output socket is provided enabling connection to extra
slave amplifiers or a signal processor.
24V EMERGENCY OPERATION
The unit will operate from 24V batteries for use in emergency
applications. Screw terminals provided on the rear.
AMP SECTION
• Automatic variable speed fan
• Over current protection
• Load short circuit protection
• Built-in low pass filter circuit
• Output level LED VU meter
SAFETY INSTRUCTIONS
• Please read these instructions before use. DO NOT switch on
the mains power until installation is complete.
• Locate the device away from any heat source, such as
radiators, heating vents or in direct sunlight etc.
• DO NOT install in a confined space such as a cupboard or
book case. Ensure adequate ventilation of the unit.
• DO NOT expose to any form of liquid.
• DO NOT drop any foreign object or liquid inside the amplifier.
• This device should be serviced by a qualified service person.
IN THE BOX
• JD-MEDIA PA Mixer Console
• Power Cord
• Rack Mounting Brackets, Screws And Washers
• Operation manual
OPTIONAL ACCESSORIES
• A 4346 (CDR-100RDSU) CD Player / AM/FM Radio Tuner
module with FM RDS / USB
• A 4344A (TP-100RDS) AM/FM Radio Tuner module with
FM RDS
Note: The three modules listed above fit into the slot on the
PA mixer front panel. Each module includes the antenna
terminal, which fits into the PA amplifier rear panel.
• C 0377 PUSH-TO-TALK Paging Mic which connects using
only a 3-Pin XLR Jack.
Note: These are the accessories which are supported for this
product in Australia, and which have descriptions within this
manual, as well as having their own manuals.
INSTALLATION
MOUNTING
These amplifiers are designed to fit into standard 19” racking
space, and include the left and right mounting brackets in the
box.
COOLING
When installing in a rack frame, never block the air vents on the
side, and make sure there is enough space (44mm) on either
side of the amplifier to allow air flow. Check the temperature
inside the rack system to ensure it is not above 40 degrees
Celsius. A cooling fan on the rear rack panel is recommended.
JDM®4 Zone Public Address Amplifiers
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JDM®4 Zone Public Address Amplifiers
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FRONT PANEL CONTROLS
1. POWER SWITCH
Push to switch on. Power LED will illuminate when on.
2. MASTER
This knob is used for adjusting the volume of the output audio
mixed from all five sources.
3. TREBLE
This control is used for adjusting the high frequency sound to the
Master Volume output.
4. BASS
This control is for adjusting the low frequency sound to the
Master Volume output.
5. PHONO / LINE
This knob adjusts the volume of the input for channel 5, which
can be either a phono or line input as selected by the rear panel
switch.
6. CH2-4
These knobs adjust the volume of the mic or line input as
selected by the rear panel switch of CH2-CH4.
7. CH1
Adjusts the volume level of MIC 1.
8. CH-1 INPUT JACK
6.35mm MIC input socket.
9. CHIME
Pressing this switch will activate the tone chime circuity.
This is a 4 tone ascending BONG BONG BONG BONG sound.
10. SIREN
Pressing these switches will activate the siren tones. Two sound
patterns are offered, depending on which button is pressed. One
tone is continuous; the other tone varies in pitch in a repeating
cycle.
11. SPEAKER SELECTOR (SP1-SP4)
These switches activate the amplifier speaker zones. Any zones
can be set to any output loading, but the total output loading must
not exceed the amplifiers maximum loading specification.
12. LEVEL METER
LED VU Meter displays the audio output level.
13. BLANK PANEL (PACK)
This is used for mounting the optional tuner (A4344A) or CD
player (A4346) modules or ‘PACKs’, which can be installed into
front panel slot, with the complementary antenna module being
installed on the rear.
14. PACK (BASS & TREBLE)
These BASS and TREBLE knobs control the bass and treble
signals of the optional tuner or CD player (also called ‘PACK’),
but only when either is installed in the front slot of the amplifier.
Fig 1: Front Panel Layout

JDM®4 Zone Public Address Amplifiers
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REAR PANEL CONTROLS
1. AC POWER
2. IMPEDANCE
This is for selecting the impedance of the high impedance
speaker terminals.
3. DC 24V TERMINAL
This terminal is for connecting the 24V battery for battery
operation.
WARNING: Ensure the correct battery polarity to prevent
damage to the amplifier.
4. FUSE HOLDER
This fuse holder contains the power fuse(T 2AL 250V). Ensure it
is replaced with same type of fuse when it blows. If it
continuously blows, there may be an amplifier fault. Please
contact a qualified service technician.
5. ANTENNA
Only fitted when either a tuner (A4344A) or CD (A4346) module
is installed. See Fig 4 for wiring.
NOTE: The picture of the amplifier’s rear panel above shows the
antenna terminal in place. This section of the amplifier’s rear
panel is blocked by a removable ‘knock-out’ section of metal
plate, which needs to be punched out and removed in order for
the antenna terminal to be screwed in place.
6. M.O.H (MUSIC ON HOLD)
Used for connecting to the telephone system when a tuner or CD
module is installed.
NOTE: The tuner or CD player output volume for music on hold
is set at a fixed level, and is not adjustable via the front panel or
module volume controls.
7. REMOTE CHIME
When these terminals are shorted, the chime is activated.
8. TEL IN
These terminals are for connection to a telephone system for
paging. Use an Austel approved line isolation unit with this input.
NOTE: When paging, all other input signals except AMP IN are
muted.
9. CH2-4 INPUT SOCKETS
These are for microphone or line inputs. Microphone input
sensitivity and impedance is 3mV/600 ohm. Line input is
300mV/50k ohms.
The XLR sockets of channels 2 and 3 have been designed for
Mic or Line input. Use the switch beside the XLR socket to
accommodate either.
NOTE: Pin 1 on the XLR and the Sleeve on the phone jack are
grounded.
10. MUTE
This adjusts the muting level when a signal is muted by MIC1,
CHIME or SIREN.
11. LINE–MIC
Set this switch to the desired input type. On CH4, it will switch
between XLR and RCA input options.
12. LINE–PHONO
This channel 5 input is for a magnetic cartridge turntable or a line
level input via RCA jacks, such as a cassette deck, CD/DVD
player etc.
13. LINE–PHONO
Set this switch to the desired input type for channel 5.
14. PRE AMP OUT–AMP IN
This jack is for connecting line level output signal to external
amplifier or a signal processor such as an equalizer.
15. SPEAKER TERMINALS
Refer to the speaker connection terminals Fig. 3a, 3b and 3c
WARNING.
• DO NOT connect speakers to more than one terminal
type. That is, connect only to the four ohm, or only to the
eight ohm, or only to the high impedance terminals.
• DO NOT connect speakers to the four ohm or eight ohm
terminals where the power rating of the speakers is less
than the power rating of the amplifier.
• For the high impedance terminals DO NOT connect
speakers where the total impedance is less than the rated
impedance (see Fig. 3c). Failure to follow this may result
in damage to the amplifier and / or speakers.
16. PHANTOM POWER
These dip switches provide CH2 and CH3 with phantom power
for condenser microphones.
IMPORTANT: When using phantom power, turn the CH2 and
CH3 volume control knobs on the front panel anti-clockwise
to decrease the level, so as to avoid damaging the speakers.
Fig 2: Rear Panel Layout

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Fig 3a, b, c: Connect speakers as per these diagrams. Ensure power is off before connecting or disconnecting speakers.
Fig 3a Fig 3b
Fig 3c

JDM®4 Zone Public Address Amplifiers
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TELEPHONE
PABX UNIT
TELEPHONE PAGING INPUT
MUSIC ON HOLD
SPEAKERS
SPEAKERS
SPEAKERS
BALANCED
INPUT SOURCE
AUX INPUT SOURCE
EG: CD PLAYER
Fig 4: Connection Guide

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SPECIFICATIONS
A 4320 Power: ........................................................60 watts RMS
A 4322 Power: ......................................................120 watts RMS
Distortion: ................................................................< 1% @ 1kHz
Signal to Noise Ratio....................................Line: >70dB Mic: >60dB
Frequency Response..........................................80Hz - 15kHz, ±3dB
Mic input sensitivity:................................................3mV balanced
Line inputs sensitivity: ........................................................300mV
Phono input sensitivity: ......................................................2.4mV
Telephone input..................................................................245mV
Bass: ..................................................................±10dB @ 100Hz
Treble: ................................................................±10dB @ 10kHz
A 4320 Standby current (DC operation): ..............................0.42A
A 4322 Standby current (DC operation): ..............................0.38A
Power supply: ................................................240V AC or 24V DC
Dimensions: ........................................≈420W x 320D x 110H mm
A 4320 weight: ....................................................................10.5kg
A 4322 weight: ....................................................................12.5kg
Fig 5: Block circuit diagram.

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During the warranty period, we undertake to repair or replace your product at no charge if found to be defective due to a manufacturing
fault. The warranty excludes damage by misuse or incorrect installation (i.e. failure to install and operate device according to
specifications in the supplied instruction manual), neglect, shipping accident, or no fault found, nor by use in a way or manner not
intended by the supplier.
For repair or service please contact your PLACE OF PURCHASE.
Our goods come with guarantees that cannot be excluded under the Australian Consumer Law. You are entitled to a replacement or
refund for a major failure and for compensation for any other reasonably foreseeable loss or damage. You are also entitled to have the
goods repaired or replaced if the goods fail to be of acceptable quality and the failure does not amount to a major failure.
JDM warrants this product for two years from the date of purchase from its resellers to the consumer. If this item is part of an
installation or another product, please contact the installer or supplier for your warranty.
Note: Under no circumstances should you attempt to repair the device yourself or via anon-authorised JDM service
centre, as this will invalidate the warranty!
It is at JDM distributors discretion as to whether the goods will be repaired or replaced (whilst under warranty); and as to whether
identical goods will be used to replace the item due to changes of models / products.