AMC a4x120d User manual

IMPORTANT SAFETY INSTRUCTIONS
When using this electronic device,
asic precautions should always e
taken, including the following:
1. Read all instructions before using the product.
2. Do not use this product near water (e.g., near a bathtub, washbowl, kitchen sink, in a
wet basement or near a swimming pool etc).
3. Use this device when you are sure that amplifier has a stable base and it is fixed securely.
4. his product, in combination with loudspeakers may be capable of producing sound
levels that could cause permanent hearing loss. Do not operate for a long period of
time at a high volume level or at a level that is uncomfortable. If you experience any
hearing loss or ringing in the ears, you should consult with otorhinolaryngologists. he
product should be positioned so that proper ventilation is maintained.
5. he product should be located away from heat sources such as radiators, heat vents, or
other devices (including amplifiers) that produce heat.
6. he product should be connected to a power supply that is described in the operating
instructions or are marked on the product. Replace the fuse only with one of the
specified type, size and correct rating.
7. he power supply cord should be undamaged and never share an outlet or extension
cord with other devices so that the outlet or extension cord's power rating is
exceeded. Never leave device plugged into the outlet when it is not being used for a
long period of time.
8. Care should be taken so that objects do not fall into, and liquids would not be spilled
through, the enclosure's openings.
9. he product should be serviced by qualified service personnel if:
•he power supply cord or the plug has been damaged.
•Objects have fallen into or liquid has been spilled on the product.
•he product has been exposed to rain.
•he product has been dropped or the enclosure damaged.
10. here are some areas with high voltage inside, to reduce the risk of electric shock do not
remove cover of the amplifier. he cover should be removed by the qualified personnel only.
No user servicea le parts inside.

CON EN S:
Before you start
Introductions 4
Features 4
Operation
Front panel 5
Rear panel 5
Function description 6
Output terminal 7
Controls and connectors
Connectors 8
Cable wiring examples 8
Block diagram 11
Specifications
General specifications 12

Introduction
hese A4X120D four channel D - class power player amplifiers are designed for public address systems
such as: paging, announcements and background music broadcasting in industrial plants, offices,
schools, shopping centers, night clubs, dinning rooms, conference hall, auditoriums and recreations
areas.
Features
•Four free-standing D - class amplifiers with 120W rated power.
•Switching power supply.
•Balanced XLR input and link connectors.
•Phoenix output connectors
•HPF filter for each input.
•Independent input level controls for each channel.
•Signal, protect and clip indicators.
•Multi-stage protection from, over-heating, over-current, short circuit, low output impedance and DC
voltage.

Front Panel
1. Handle
2. Cooling vent
3. Status indicators
4. Power switch
Rear Panel
1. Power connector and AC fuse ( 4AL 250V)
2. Phoenix output
3. Balanced XLR input
4. Balanced XLR link output
5. HPF 400Hz filter switch
6. Input level control
7. Cooling vent

Functions description
HANDLES
For easy transport while carrying, or while rack mounting, the amplifier features two handles located
conveniently on the left and right sides of the front panel.
COOLING VENTS
Cool air is pulled in through the front panel fan filters and eliminated through the rear panel vents.
CLIP LED
Lights whenever the channel is outputting signal at full strength and signal is distorted. Reduce signal level
to ensure undistorted output signal.
PROTECTION LED
his LED lights up for approximately one second after the A4X120D is powered on and then turns off if the
amplifier is not damaged. his LED also lights when overheating or other severe problems occur. It is
normal for the protection LED to fade slowly when the amplifier is powered off.
SIGNAL LED
LED in the front panel indicates audio signal of the corresponding channel.
POWER SWITCH
Use this switch to power on or off the amplifier. he LED in the front panel lights up if the amplifier is
powered on.
POWER CONNECTOR
Power connector is designed for main powers connecting to amplifier. his connector is combined with
fuse holder and 4A, 250V fuse.
PHOENIX OUTPUT
Use these to connect each channel with A4X120D to 4 Ω or 8 Ω loudspeakers, or to one of the 70 and 100
volt outputs if you are using a constant voltage system.
BALANCED XLR INPUT
Connect audio signal to these electronically balanced connectors. Please note that the A4X120D needs
atleast 0 dBu to achieve maximum power.
LINK
Connects outgoing signals from these XLR connectors. Input and link connectors are connected with each
other directly.
HIGH PASS FILTER
HPF filter reduce low frequency is in the audio signal.
LEVEL CONTROL
hese controls allow you to precisely adjust the input level of the signal arriving at the rear-panel input
connectors. At their fully counterclockwise position, the signal is attenuated by -12 dB. At their fully
clockwise position, the signal is no attenuated. When 0dBu of signal arrives at the input and the input level
controls are set to their fully clockwise position (0dBu), the Amplifier delivers full power.

Output terminal
Each of the amplifier channels can run only one output configuration at the same time. Operating
amplifiers using 4 ohm and 70 or 100 volt concurrently may cause damage to the amplifier or
connected speakers.

Connectors
S connector
RS connector
XLR male connector XLR female connector
RCA connector
Cable wiring examples
Cable to balanced input from balanced output. RS connectors.

Cable to unbalanced input from balanced output. RS and S connectors.
Cable to balanced input from unbalanced output. S and RS connectors.
Cable to unbalanced input from unbalanced output. S connectors.
Cable to balanced input from balanced output. XLR connectors.
Cable to unbalanced input from balanced output. XLR and S connectors.
Cable to balanced input from unbalanced output. S and XLR connectors.

Cable to balanced input from balanced output. RS and XLR connectors.
RCA cable.
Cable to unbalanced input from RCA output. RCA and S connectors.
Cable to balanced input from RCA output. RCA and XLR connectors.
Cable to balanced input from RCA output. RCA and RS connectors.
Cable to RCA input from balanced output. RCA and XLR connectors.
Cable to RCA input from balanced output. RCA and RS connectors.

Block diagram

General specifications
Power supply AC 230 V, 50 Hz
Output power 4 x 120 W
AC power consumption (Stand y) 33 W
AC power consumption 550 W @ RA ED POWER
Total harmonic distortions < 5 %
Input sensitivity 0 dBu
Max input level + 26 dBu
S/N ratio 90dB
Frequency response 50 Hz – 18 kHz +/- 3 dB
Protection Short circuit, thermal, current limit, DC offset,
current inrush, RF protection, urn on/ urn off
muting.
Cooling Fan forced air.
Indicators Power on, protection, signal, clip.
Controls Power switch, input level, HPF filter.
Output 100 V, 70 V, 22 V
Dimensions 88 mm (H) x 482 mm (W) x 433 mm (D)
Weight 17,8 kg
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