AMC XA User guide

XA
2/4 CHANNEL
POWER AMPLIFIER
IA

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1. Although the AMC XA is designed with high efficiency digital amplifiers, it still
generates modest amounts of heat, adequate ventilation is required. We therefore
recommend users not to place the XA amplifier on a soft surface such as a carpeted
surface, etc.
2. CAUTION: To prevent the risk of fire or shock, do not allow any liquid or moisture to
enter into the internal parts of this product. If any liquid accidentally enters this
product, shut off the power and remove the AC power cord immediately. If the liquid is
anything other then clean water or pure alcohol, have the product examined by a
service technician. Servicing of this product should be referred to a qualified service
technician.
INSTALLATION NOTES

1. AC INLET
2. 2CH/BRIDGE SWITCHES
3. INPUTS
4. INPUT LEVEL CONTROLS
5. RS232 Connector
6. LOUDSPEAKER TERMINALS
7. AUDIO SENSE/ TRIGGER/
CONSTANT SWITCH
8.IRIN&IROUT
9. FUSE
1. POWER SWITCH AND POWER
INDICATOR
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9566 7
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REAR PANEL CONNECTIONS/FRONT PANEL CONTROLS
REAR PANEL
FRONT PANEL

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1. AC INLET
2. 2CH/ BRIDGE SWITCHES.
3. INPUTS.
4. INPUT LEVEL CONTROLS.
5. RS232 Connector.
6. SPEAKERS TERMINALS
Plug one end of the AC line cord into the
AC INLET and the other end into a
nearby wall outlet that provides the
correct AC power line voltage, or into a
convenience outlet on any other AMC
product.
There are two slide switches on the back
panel labelled "2CH/BRIDGE". These
switches allow the XA to operate in
several modes depending on the number
of loudspeakers to be connected. These
modes of operation are defined as
follows;-
With both switches
in the BRIDGE position, the XA becomes
a two channel (stereo) amplifier capable
of driving two 8 ohm loudspeakers at 90
watts per channel. In this mode, the XA
can be used as a high power, audiophile
quality, stereo power amplifier.
CAUTION: In the BRIDGE mode, the
speaker terminals should be directly
wired to the loudspeaker and not to any
accessory device like sub-woofer
amplifier network or headphones
adaptors etc that may share a common
ground with other channels.
With both switches
in the 2CH. position, the XA becomes a
four channel amplifier capable of driving
four 4 ohm loudspeakers at greater than
45 watts per channel. In this mode, the
XA can be used for Dolby surround sound
systems , multi-room type and bi-amp
applications.
There are four RCA phono connectors on
the back panel that connect to the inputs
of each of the four power amplifiers.
Connections to these inputs are made
with reference to the MODE SWITCH
settings described above;-
Connections for the CH
A can be made via L RCA input connector
of CH A and for the CH B input, use the L
RCA input connector of CH B.
NOTE: In this mode, the input phono
connectors of R RCA input connectors
are disconnected.
In this mode, the XA
operates as a 4 channel amplifier.
Connections to the inputs of these
amplifiers are made through the RCA
phono connectors of L & R RCA
connectors of CH A & CH B.
Each channel of the XA has its own,
independent level control. Before turning
on the XA for the first time, make sure
that all level controls are set to their fully
clockwise position. These controls can be
used for various functions. For example,
they can be used to match the levels of
loudspeakers in a multi-room installation,
or to lower the sensitivity of the power
amplifier, so that the volume control on
the pre-amplifier is at a more convenient
and usable position. They can also be
used to optimise the balance in a stereo
system.
NOTE: In the Bridge mode, only the input
level controls of L of CH A & CH B are
operative.
XA can be hooked to a control system
through the RS232 connector. The XA
canbehookeduptoUSBHubor
Ethernet Switch through RS232 to USB
or RS232 to Ethernet adaptor. Through
the RS232 connector the control system
can turn XA ON or OFF. For details of
commands, please refer to appendix I.
The XA is equipped with 4-circuit plug-
able Terminal Blocks allow quick
connections of the internal amplifiers to
stereo pairs of speakers in the various
zone rooms. They accept wire sizes for
14 to 28 AWG. The following describes
the connections for Bridge and 2 CH
operations;-
2 CHANNEL MODE.
4 CHANNEL MODE.
BRIDGE MODE.
2CHMODE.

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2 CH MODE.
BRIDGE MODE.
When the MODE SWITCH
of the XA are set to 2 CH operation,
simply connect the wires from L
loudspeakers to the L sides of speaker
terminal blocks (marked - and +) of CH A
& CH B and R loudspeakers to the R
sides of speaker terminal blocks (marked
- and +) of CH A & CH B. Make sure that
the red terminal on each loudspeaker is
connected to the corresponding +
terminal on each speaker terminal block
and likewise for the black terminal on
each loudspeaker to each - terminal on
each speaker terminal block .
When the MODE
SWITCHES are set to BRIDGE mode
operation, only the + terminals on the
speaker terminal blocks of XA are used.
For this mode of operation, connect the
red terminal of the right speaker to the L+
terminal of CH A speaker terminal block
and the black speaker terminal to the R+
terminal of CH A speaker terminal block.
The left speaker is connected in a similar
way, where the red terminal of the
speaker is connected to the L+ terminal
of CH B speaker terminal block and the
black terminal of the speaker is
connected to the R+ terminal of CH B
speaker terminal block.
NOTE: The XA amplifier is normally used
in Bridge or 2 CH modes for both CH A
and CH B. However, it can also can be
set to operate as CH A for 2CH and CH B
for bridge mode. So the XA will be
capable of driving one 8 ohm loudspeaker
at 90 watts and two 4 ohm loudspeakers
at greater than 45 watts per channel.
Typical applications include,
satellite/subwoofer systems and Dolby
surround sound decoder systems. To set
the XA in this mode of operation, please
consult your AMC dealer.
7. AUDIO SENSE/TRIGGER/CONSTANT
SWITCH
The remote power switch is located on
the back panel of the AMC XA and
provides the following functions;
When the remote power
switch is set in the AUDIO SENSE
position, the XA is turned on or off
automatically, depending on the audio
signal level at the inputs. With an audio
signal greater than 10 mV at any of the
four stereo inputs of XA, the amplifier will
automatically turn on. If the signal level
drops below this level, the amplifier will
remain on for a period of approximately 5
minutes before it automatically reverts to
standby mode.
Please note that when AC power is first
applied to the XA while the remote power
switch is in the AUDIO SENSE position,
the amplifier will automatically turn on,
even without an audio signal being
present at any of the audio inputs.
However, after approximately 5 minutes,
the amplifier will revert to standby mode,
assuming no signals are present at any of
the inputs.
When the remote power
switch is set in the TRIGGER position,
the AMC XA can be turned on
automatically by an external trigger
voltage. The trigger voltage is applied to
the trigger input socket, located on the
back panel of the XA.. This trigger voltage
can originate from a system controller or
from another XA. The sensitivity of this
input ranges from +3Vdc to +30Vdc and
will also accept AC voltages over the
same range. The current required from
the trigger source is only 0.2mA.
The XA is also provided with a trigger
output socket, also located on the back
panel. When the XA is turned on, the
trigger output socket provides a +12Vdc
signal that can be looped through or
"daisy-chained" to the trigger input of
another XA amplifier (or other
component) in a multi component
installation. When the external trigger
voltage is set to 0V, the XA will be in
standby mode and the voltage from the
AUDIO SENSE.
TRIGGER.

trigger output socket will likewise be 0V.
When the remote power
switch is set in the CONSTANT position,
the power on and off states of the AMC
CONSTANT.
XA are controlled by the front panel
master power on/off switch.
NOTE: The bi-color power LED above the
front panel power switch, indicates the
power status of the XA. This LED will light
up RED when the XA is in stand-by mode
and GREEN when turned on.
8. IR IN & IR OUT
9. FUSE
FRONT PANEL.
1.POWER SWITCH AND POWER.
IR signal from rooms or IR OUT of other
units can be connected to the 3.5mm mini
IR IN jack on the rear panel of XA. So, XA
can be controlled by the IR remote control
in each room through IR sensor. There is
IR OUT as buffered output of IR IN for
controlling units hooking up to XA or
operating as daisy chain for the IR signal
passing through the system.
There is T2AL 250 fuse put inside the
fuse holder besides AC Inlet. Replace
always with the same type of fuse.
The press button switch marked power
can be used to switched the XA on or off.
When the XA is switched on, the led
above the power switch will light up.
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SPECIFICATIONS
Weltronics Corp. reserved the right to improve its products at any time. Specifications are
subject to change without notice.
SPECIFICATIONS:
BRIDGE MODE
2 CHANNEL MODE
Power output into 8 ohms (20Hz~20KHz) ............................................................90W
With both channels driven
Rated THD. .......................................................................................................0.05%
Damping factor ....................................................................................................>100
Input sensitivity for 1W/90W into 8 ohm .............................................110mV/1000mV
Power output into 4 ohms (20Hz-20KHz) .............................................................45W
With all channels driven
Rated THD. .......................................................................................................0.05%
Damping factor ....................................................................................................>100
Input sensitivity for 1W/45W into 4 ohms .............................................100mV/680mV
Input impedance ................................................................................R=10K C=200pf
Frequency response 20Hz~20KHz ................................................................+/-0.5dB
"A" WTD. singal to noise ratio (ref. 1W/8 ohms) ...............................................100dB
Dimensions (WxHxD) ...................................................................482.6x53.3x284.7mm
Net weight ..............................................................................................................4.3kg
Shipping weight (2 in 1).......................................................................................15.15kg
Power consumption .............................................................................................. 120W
Specifications are subject to change without notice.

APPENDIX I - SERIAL COMMUNICATION
SPECIFICATIONS
*RS232 asynchronous serial
communication
*9600 bps, 8 bits, 1 stop bit, no parity
*no flow control
Full command format:
Full command format is based on human
readable ASCII characters. All codes are
separated with field separators and
terminated by line terminator.
field separator
separator for fields in the command line
one or more spaces
line terminator
terminator for the command line
CR, LF, CR/LF, or LF/CR
Turn Power On:
POWER ON<CR>
Turn Power Off:
POWER OFF<CR>
Read Power Status:
POWER<CR>
RETURN: "ON" or "OFF"
Power Toggle:
POWER TOGGLE<CR>
Display unit identity:
Display the brand name of this unit:
BRAND<CR>
Display the model name of this unit:
MODEL<CR>
Display the current version of the
firmware:
VERSION<CR>
Reset unit:
Reset and reboot the system by
issuing the following command:
RESET<CR>
To restore all "Setup" values to factory
default:
FACTORY<CR>
To enter firmware upgrade mode:
FIRMWARE<CR>
After software upgrade mode is entered,
the firmware upgrade software needs to be
executed from a PC or supplied upgrade
system in order to start the upgrade
process.
To enter test mode:
TEST<CR>
HARDWARE SPECIFICATION
SOFTWARE SPECIFICATION
COMMAND REFERENCE
Power On/Off
System Commands
Restore to factory default:
Enter firmware upgrade mode:
Enter test mode:

All the safety and operating instructions should be read
before the appliance is operated.
The safety and operating instructions should be retained for
future reference.
All warnings on the appliance and in the operating instructions
should be adhered to.
All operating and use instructions should be followed.
The appliance should not be used near water - for example,
near a bathtub, washbowl, kitchen sink, laundry tub, in a wet
basement, or near a swimming pool, etc.
The appliance should be used only with a cart or stand that is
recommended by the manufacturer.
An appliance and cart combination should be
moved with care. Quick stops, excessive force,
and uneven surfaces may cause the appliance
and cart combination to overturn.
This equipment is not designed for use mounted on a wall or a
ceiling.
The appliance should be situated so that its location or position
does not interfere with its proper ventilation. For example, the
appliance should not be situated on a bed, sofa, rug, or similar
surface that may block the ventilation openings, or placed in a
built-in installation, such as bookcase or cabinet that may
impede the flow of air through the ventilation openings.
The appliance should be situated away from heat sources
such as radiators, heat registers, stoves, or other appliances
(including amplifiers) that produce heat.
The appliance should be connected to a power supply only of
the type described in the operating instructions or as marked
on the appliance.
Power-supply cords should be routed so that they are not likely
to be walked on or pinched by items placed upon or against
them, paying particular attention to cords at plugs,
convenience receptacles, and the point where they exit from
the appliance
The appliance should be cleaned only as recommended by
the manufacturer.
The power cord of the appliance should be unplugged from the
outlet when left unused for a long period of time.
Care should be taken so that objects do not fall and liquids are
not spilled into the enclosure through openings.
The user should not attempt to service the appliance beyond
that described in the operating instructions. All other servicing
should be referred to qualified service personnel.
The appliance should be serviced by qualified service
personnel when:
a) The power-supply cord or the plug has been damaged; or
b) Objects have fallen, or liquid has been spilled into the
appliance; or
c) The appliance has been exposed to rain; or
d) The appliance does not appear to operate normally or
exhibits a marked change in performance; or
e) The appliance has been dropped, or the enclosure is
damaged.
(APPLIES TO TUNER AND RECEIVERS ONLY)
An outdoor antenna should be located away from power lines.
(APPLIES TO TUNER AND RECEIVERS ONLY)
If an outside antenna is connected to the receiver, be sure the
antenna system is grounded so as to provide some protection
against voltage surges and built up static charges.
Section 810 of the National Electrical Code,ANSI/NFPA No.
70-1984, provides information with respect to proper
grounding of the mast and supporting structure, grounding of
the lead-in wire to an antenna discharge unit, size of grounding
conductors, location of antenna-discharge unit, connection to
grounding electrodes, and requirements for the grounding
electrode. See Figure.
a) Use No. 10 AWG (5.3 mm ) copper, No. 8 AWG (8.4 mm )
aluminum, No. 17 AWG (1.0 mm ) copper-clad steel or
bronze wire, or larger, as a ground wire.
b) Secure antenna lead-in and ground wires to house with
stand-off insulators spaced from 4-6 feet (1.22-1.83 m)
apart.
c) Mount antenna discharge unit as close as possible to where
lead-in enters house.
d) Use jumper wire not smaller than No.6 AWG (13.3 mm )
copper, or the equivalent, when a separate antenna-
grounding electrode is used. See NEC Section 810-21(j).
1. READ INSTRUCTIONS
2. RETAIN INSTRUCTIONS
3. HEED WARNINGS
4. FOLLOW INSTRUCTIONS
5. WATER AND MOISTURE
6. CARTS AND STANDS
6A.
7. WALL OR CEILING MOUNTING
8. VENTILATION
9. HEAT
10. POWER SOURCES
11. POWER-CORD PROTECTION
12. CLEANING
13. NON USE PERIODS
14. OBJECT AND LIQUID ENTRY
15. SERVICING
16. DAMAGE REQUIRING SERVICE
17. POWER LINES
18. OUTDOOR ANTENNA GROUNDING
22
2
2
SAFETY INSTRUCTION
S3125A
PORTABLE CART WARNING
Antenna Lead
In Wire
Ground
Clamp
Electric
Service
Equipment
Power Service Grounding
Electrode System
(NEC Art 250 Part H)
Ground Clamps
Antenna
Discharge
Unit (NEC
Section 810.20)
Grounding Conductors
(NEC Section 810.21)
Antenna Grounding According to
the National Electrical Code
National Electrical Code
Available from Library, book
stores, or National Fire Protection
Association (Batterymarch Park,
Quincy. MA 02269).
AMC 21-3004

PN: 21-4081