AMC MA 21 User manual

User
Manual
MA 21
Two zone mixing amplifier

Safety instructions
USER MANUAL MA 21 Two zone mixing amplifier
When using this electronic device, basic precautions
should always be taken, including the following:
1Read all instructions before using the product.
2Do 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.
4This 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.
5The product should be located away from heat sources such as radiators,
heat vents, or other devices that produce heat.
6The product should be connected to a power supply that is described
in the operating instructions or are marked on the product.
7The power supply should be undamaged and never share an outlet
or extension cord with other devices. Never leave device plugged
into the outlet when it is not being used for a long period of time.
8Care should be taken that objects do not fall into liquids and liquids
would not be spilled on the device.
9The product should be serviced by qualified service personnel if:
– The power supply or the plug has been damaged.
– Objects have fallen into or liquid has been spilled on the product.
– The product has been exposed to rain.
– The product has been dropped or the enclosure damaged.
10 There are some areas with high voltage inside, to reduce the risk of electric
shock do not remove cover of the amplifier.
The cover should be removed by the qualified personnel only.
CAUTION
To reduce the risk of electric shock, do not remove screws.
No user-serviceable parts inside. Refer servicing to qualied
service personnel. To reduce the risk of re, electric shock
or product damage, do not expose this apparatus to rain,
moisture, dripping or splashing and that no objects lled
with liquids, such as vases, shall be placed on the apparatus.
RISK OF ELECTRIC SHOCK
DO NOT OPEN

x
y
y
x
25
o
Maximum Usage 65mm
Minimum Usage 18mm
Minimum Usage 18mm
y
y
25
x
x
y
Minimum Usage 18mm
Minimum Usage 18mm
Minimum Usage 18mm
Maximum Usage 65mm
Maximum Usage 65mm
25
25
o
x
x
M
M
M
Ma
Mi
M
M
M
M
M
M
y
Max
Min
y
Mi
a
a
axi
ni
n
n
n
n
x
x
xim
nim
i
i
mu
mu
m
m
m
m
m
m
mu
mum
u
u
u
u
u
u
um
um
m
m
m
m
m
m
m U
m U
m
m
m
U
U
U
U
U
U
Us
Us
Us
U
U
sa
sa
a
ag
ag
g
g
g
g
g
ge
ge
g
g
g
g
g
g
ge 6
e 1
e
e
e
65
18
1
6
6
65
18m
8
8
8
8
65
5
5m
8m
8m
5m
m
y
mm
mm
m
y
y
m
m
m
m
m
mm
m
m
m
m
m
m
m
x
Table of contents
USER MANUAL MA 21 Two zone mixing amplifier
Before you start
Introduction......................................................................................................................................................3
Features................................................................................................................................................................3
Operation
Front panel ........................................................................................................................................................4
Rear panel...........................................................................................................................................................4
Function description of MA 21 amplifier......................................................................................5
Function description of paging microphone Talk St Z2...................................................7
Specifications
General specifications................................................................................................................................8

USER MANUAL MA 21 Two zone mixing amplifier
Before you start
MA 21 two zone mixing amplifiers for commercial and industrial applications. Possibility to plug in two zone
paging microphone or set microphone input to selected zone by using logic inputs in 5 pin XLR conector.
Low impedance speaker lines designed in paralel to 100 V outputs. Line input selector for each zone allows to
broadcast different background music into zones.
Amplifier is ideal for two zone application, but can be used in stereo background music system as well.
FEATURES
• Two100Vorlowimpedancezones
• ABclassaudioamplier
• Lineinputselectorforbothzones
• XLRmicrophoneandcontrolinputs
• PriorityinputMIC1
• Connectorfortwozonepagingmicrophone
• Separatetoneandmastercontrolforbothzones
• XLRandRCAinputsconnectors
• RCApreampoutput
03

USER MANUAL MA 21 Two zone mixing amplifier
Front Panel
Rear Panel
1. Mic input level control |2. Line input selector |3. Line input level control |4. Tone control - bass |5. Tone control - treble
6. Zone 2 master level control |7. Zone 1 master level control |8. Output level indicator |9. Power switch
1. Main powe connector and fuse 2. Main voltage selector |3. 100V amplifier output |4. low impedance output |5. preamp output |6. line level audio input
7. paging micropohe input |8. microphone input
Operation
04
1 96 75432 8
1 2 3 4 567 8

USER MANUAL MA 21 Two zone mixing amplifier
Function description of MA 21 amplifier
MIC INPUT LEVEL CONTROL
These rotary knobs are designed for adjusting volume level of the 3 pin and 5 pin
XLR inputs. First three inputs can be used for microphone level audio only.
LINE INPUT SELECTOR
This knob allows to select and broadcast to zone one of three audio source con-
nected to line level RCA inputs. Individually for both zones input selector gives a
opportunity to broadcast different background music to different zones.
LINE INPUT LEVEL CONTROL
These two knobs designed for adjusting volume level of line audio input.
TONE CONTROL
The separate tone controls provide attenuation of bass and treble response. The
flat position is obtained when the knobs are set to middle position. Turn bass
control knob (BASS) and treble tone control knob (TREBLE) clockwise to raise
tone level by approximately +10 dB; turn counterclockwise to lower tone level by
approximately -10 dB.
MASTER LEVEL CONTROL
This potentiometer is designed to adjust audio level in the main output.
OUTPUT LEVEL INDICATOR
These two led bars indicates output signal amplitude of both zones. If the red led indi-
cator starts lighting continuously please decrease the sound volume by using master
control, because red led bar indicates too high signal level. First led in led bar is main
power indicator.
POWER SWITCH
Use this switch to power on or off the amplifier. Green led in the front panel led
bar lights up if the amplifier is powered.
MAIN POWER CONNECTOR AND FUSE
Power connector is designed for main powers connecting to amplifier. This con-
nector is combined with fuse holder and 4A 250V fuse.
MAIN VOLTAGE SELECTOR
Allows to select main power voltage. Set the proper voltage before the first time
turning on amplifier according to your area: ~115 V (60 Hz) or 230 V (50 Hz).
05
Operation

USER MANUAL MA 21 Two zone mixing amplifier
Function description of MA 21 amplifier
100V OUTPUT
Output terminal is designed to connect speaker line to amplifier. There are availa-
ble two types of output: low impedance 8 Ω and 100 V outputs for constant volt-
age audio line. Each of the amplifier zones can run only one output configuration
at the same time. Operating amplifier using 8 Ω and 100 volt concurrently may
cause damage to the amplifier or connected speakers.
LOW IMPEDANCE OUTPUT
Output designed for 8 Ω loudspeakers. Operating amplifier using 8 Ω and 100
volt concurrently may cause damage to the amplifier or connected speakers.
PREAMP OUTPUTS
This is line level RCA output to connect audio recording equipment or any other
purpose. Subwoofer out and record out are the same type preamp output con-
nected in parallel inside the amplifier.
LINE LEVEL AUDIO INPUT
RCA input for line level audio. Signal from line inputs can be selected and broadcast to
zones by using line input selector located in the front panel.
PAGING MICROPHONE INPUT
This input is designed to connect Talk St Z2 paging microphone to amplifier. 5
pin XLR connector’s audio inputs pin’s and 3 pin XLR are connected in parallel
with each other, because of this reason please connect only one microphone in
one MIC input.
Paging microphone input pinout 5pin XLR connector:
1. GND |2. MIC audio signal + |3. MIC audio signal - |4. Zone 2 mute trigger |
5. Zone 1 mute trigger
MIC 2 and MIC 3 input zoning can be controlled by external buttons, relays or
external devices as well.
Application and circuit diagram:
Microphone is muted in both zones
Microphone is muted in zone 2
Microphone is muted in zone 1
MICROPHONE INPUT
This is balanced microphone input. This input as well as MIC 2 and MIC 3 inputs
are suitable for dinamic microphones only. MIC 1 input is priority input.
06
Operation

USER MANUAL MA 21 Two zone mixing amplifier
Function description of paging microphone Talk St Z2
INPUT CONNECTOR
Designed to connect gooseneck microphone. 3 pin XLR connector.
ZONE 1 SWITCH
Disables microphone mute in zone 1 and allows make announcement
in this zone.
ZONE 2 SWITCH
Disables microphone mute in zone 2 and allows make announcement
in this zone.
ALL ZONES SWITCH
Disables microphone mute in zone 1 and zone 2 and allows make announce-
ment
in these zones.
OUTPUT CONNECTOR
Designed to Talk St Z2 to MA 21 amplifier. 5 pin XLR connector. Max distance
between amplifier and Talk St Z2 is 20 m. Distance can be increased if separate
shielded microphone cable is used to transmit audio signal from Talk St Z2 to
audio amplifier.
1. Input connector |2. Zone 1 switch |3. Zone 2 switch |4. All zones switch | 5.
Output connector
1. GND |2. Audio signal + |3. Audio signal - |4. Zone 2 mute signal |5. Zone 1
mute signal
Operation
1
2
3
4
51
2
3
4
5
Talk St Z2 cable diagram
1
2 3 4
5
07

USER MANUAL MA 21 Two zone mixing amplifier
Amplifier
The specifications are correct at the time of printing this manual.
For improvement purposes, all specifications for this unit, including
design and appearance, are subject to change without prior notice.
Power supply AC 230 V/115 V 50/60 Hz
AC power consump-
tion 500 W @ full power
Output Power 2 X 100 W
Total Harmonic
Distortion 0.05 % @ 1KHz
Input sensitivity XLR - 57 dBu
RCA -10 dBu
Priority input MIC 1
Preamp out level + 2 dBu
Output 8 Ω output binding post connector
100 V output screw terminal
Frequency Response 8 Ω output 20 Hz - 20 kHz
100 V output 50 Hz - 18 kHz
SN range < 70 dB
Dimensions H x W x D 88 mm x 425 mm x 305 mm
Weight 9 kg.
09
General Specifications

AMC is a registered trademark of AMC Baltic www.amcpro.eu
Notes