Roemtech SXR-120D User manual

OPERATION MANUAL
Please follow the instructions in this manual to obtain the optimum results from this unit.
We also recommend that you keep this manual available for future reference.
ON
OFF
POWER
MIC1 INPUT
PROT
MIC /4 AUX 1 AUX 2MIC 3
MIC 1 MIC 2 MASTER
100V
70V SIG
CLIP
OL
TREBLEBASS
10 0 10 0 10 0 10 0 10 0 10 0
T-60H
HIGH EFFICIENCY MIXER AMPLIFIER
SXR-120D 70/100V CLASS D AMPLIFIER
ON
OFF
POWER
MIC1 INPUT
PROT
MIC 4/AUX 1 AUX 2MIC 3
MIC 1 MIC 2 MASTER
100V
70V SIG
CLIP
OL
TREBLEBASS
10 0 10 0 10 0 10 0 10 0 10 0
SXR-120D 70/100V
120W MIXER/AMP
120W 5Channel - MIXER/AMP
SXR-120D 70/100V

TABLE OF CONTENTS
2
1. SAFETY PRECAUTIONS ..........................................................................................3
2. FEATURES .....................................................................................................................5
3. FEATURES ILLUSTRATED
3.1 Front Panel ...................................................................................................................6
3.2 ..................................................................................................................6
4. OPERATION....................................................................................................................7
5. .............................................................................................9
6. APPLICATIONS ......................................................................................................... 10
7. BLOCK DIAGRAM ....................................................................................................11
8. SPECIFICATIONS .................................................................................................... 12
9. DIMENSIONAL DIAGRAM .................................................................................... 13
Rear Panel
TROUBLESHOOTING

Safety Symbol and Message Conventions
Indicates a potentially hazardous situation which, if mishandled, could
result in death or serious personal injury.
Indicates a potentially hazardous situation which, if mishandled, could
result in moderate or minor personal injury, and/or property damage.
When Installing the Unit
Do not expose the unit to rain or an environment
where it may be splashed by water or other liquids,
as doing so may result in fire or electric shock.
Use the unit only with the voltage specified on the
unit. Using a voltage higher than that which is
specified may result in fire or electric shock.
Do not cut, kink, otherwise damage nor modify the
power supply cord. In addition, avoid using the
power cord in close proximity to heaters, and never
place heavy objects -- including the unit itself -- on
the power cord, as doing so may result in fire or
electric shock.
Be sure to replace the unit's terminal cover after
connection completion. Because high voltage is
applied to the speaker terminals, never touch these
terminals to avoid electric shock.
When the Unit is in Use
Should the following irregularity be found during
use, immediately switch off the power, disconnect
the power supply plug from the AC outlet and
contact your nearest ROEMTECH dealer. Make no
further attempt to operate the unit in this condition
as this may cause fire or electric shock.
If you detect smoke or a strange smell coming
from the unit.
If water or any metallic object gets into the unit
If the unit falls, or the unit case breaks
If the power supply cord is damaged (exposure of
the core, cracking or fraying, etc.)
If it is malfunctioning (no tone sounds.)
To prevent a fire or electric shock, never open or
remove the unit case as there are high voltage
components inside the unit. Refer all servicing to
your nearest ROEMTECH dealer.
Do not place cups, bowls, or other containers of
liquid or metallic objects on top of the unit. If they
accidentally spill into the unit, this may cause a fire
or electric shock.
1. SAFETY PRECAUTIONS
3
Be sure to ground the unit using a properly installed
ground path to avoid electric shock. Never ground to
a gas pipe, this is an explosion hazard.
Avoid installing or mounting the unit in unstable
locations, such as a weak shelf or a slanted surface.
Doing so may result in the unit falling, causing
personal injury and/or property damage.
Do not insert or drop metallic objects or flammable
materials in the ventilation slots of the unit’s cover, as
this may result in fire or electric shock.
Be sure to read the instructions in this section carefully before use.
Make sure to observe the instructions in this manual regarding the safety precautions. Ignoring
the guidelines could severely reduce the life of the amplifier and possibly void the warranty.
It is recommended that you keep this instruction manual available for future reference.
Safety symbols and messages described below are used in this manual to prevent bodily injury and property
damage which could result from mishandling. Before operating your product, please read this manual first and
understand the safety symbols and messages so that you are thoroughly aware of the potential hazards.

When Installing the Unit When the Unit is in Use
SAFETY PRECAUTIONS
4
Never plug in or remove the power supply plug with
wet hands, as doing so may cause electric shock.
When unplugging the power supply cord, be sure
to grasp the power supply plug; never pull on the
cord itself. Operating the unit with a damaged
power supply cord may cause a fire or electric
shock.
When moving the unit, be sure to remove its power
supply cord from the wall outlet. Moving the unit
with the power cord connected to the outlet may
cause damage to the power cord, resulting in fire or
electric shock. When unplugging the power cord,
be sure to grasp the plug itself rather than pulling
on the cord.
Do not block the ventilation slots in the unit’s cover.
Doing so may cause heat to build up inside the unit,
shortening the life of the unit.
Avoid installing the unit in locations that may have
the following environments; high humidity or
steam, high dust, direct sunlight, near heaters,
smoke or steam. Doing so may void the warranty,
shorten the product life or result in electrical shock
or fire.
Do not place heavy objects on the unit as this may
cause damage to the unit and inhibit the
convective cooling. There should be adequate
space all around the unit so that it may remain cool
while in operation.
Make sure that the volume control is set to
minimum position before the power is switched on.
This unit is capable of producing extreme sound
pressure and may cause hearing damage.
Do not operate the unit for an extended period of
time when the audio is distorting or the “clip” light
on the front panel is emitting. Over time, this could
damage the unit and create excess heat.
Contact your ROEMTECH dealer as to the proper
way to clean this unit. If dust is allowed to
accumulate in and around it, this presents a fire
hazard and may also cause damage to the
amplifier.
Inspect the power cord for damage periodically
and keep it free from debris, dust and away from
sharp metal objects that could damage it. Be
certain the plug is fully inserted into the wall outlet.
If the unit is to be unused for long periods of time, it
should be powered down and unplugged.
CAUTION: When using any 70V / 100V amplifier for distributed audio, bass settings should not be set to
higher levels. This is because a phenomenon known as “transformer saturation” occurs in some
speaker transformers at frequencies typically lower than 70Hz. Once saturation begins, the speaker’s
primary transformer coil causes an exceptionally high load on the entire system. This can lead to the
destruction of the speaker transformer (a possible fire hazard) and/or an overload condition for the
amplifier.

2. FEATURES
5
1. Rated Power: 120W RMS.
2. 100V, 70V speaker outputs.
3. Six total inputs (five mixable).
4. Two line level inputs.
5. One line level emergency full override/pass-through input.
6. Four mic level inputs.
7. EMC input has priority over all inputs.
8. Override feature mutes all except EMC inputs when signal is detected on MIC 1.
9. Treble and Bass adjustments.
10. Extensive thermal, short circuit, overload and power fluctuation protection circuitry.
11. Three year ROEMTECH warranty.

ON
OFF
POWER
MIC1 INPUT
PROT
MIC /4 AUX 1 AUX 2MIC 3
MIC 1 MIC 2 MASTER
100V
70V SIG
CLIP
OL
TREBLEBASS
10 0 10 0 10 0 10 0 10 0 10 0
3. FEATURES ILLUSTRATED
6
3.1 FRONT PANEL
11 12
1 2 3 4 5 6 78 9 10
1. MIC1 unbalanced input jack
2. MIC1 volume control knob
3. MIC2 volume control knob
4. MIC3 volume control knob
5. MIC4 / AUX1 volume control knob
6. AUX2 volume control knob
7. BASS adjustment
8. TREBLE adjustment
9. Master volume control
10. PROT/100V/70V/OL/CLIP/SIG
status indicators
11. Power switch
12. Power indicator
3.2 REAR PANEL
MIC3 MIC 2 MUTE MIC 4/AUX 1EMC IN
AUDIO AUX2 AUX1
OUTPUT INPUT
L L
R R
70V/
100V
OUTPUT
70V100V
COM COM COM
13 14 15 17 19 20 21 22
16 18
13.
14. 100V/70V output terminal
15. 100V/70V speaker output switch
16. Emergency input jack (line level)
17. Dual line output (RCA)
18. Two channel AUX RCA input
19. MIC4/AUX1 input interface (passive mix)
20. MIC3 input jack
21. MIC2 input jack
22. MUTE override level
AC power input
SXR-120D 70/100V
120W MIXER/AMP

7
4. OPERATION
1.Connect the speakers:
Maximum output voltage: 70V
SPK- SPK+
70V/
100V
OUTPUT
70V100V
COM COM COM
70V/
100V
OUTPUT
70V100V
COM COM COM
①When the 100V/70V selector is switched to
the 70V position, as shown below:
②When the 100V and 70V selector switch to
100V position, as shown below:
Maximum output voltage: 100V
Note:
1. Before connecting the speakers, please make sure that the amplifier is powered off. If the amplifier
is powered on during the wiring and installation process, electric shock is likely via the speaker connections.
2. Make sure there are no short circuits along the speaker connections before power up of the amplifier.
3. During the installation of speakers, please make sure that the sum of the speaker loads does not
exceed the 120 watt rating of the amplifier.
2.Connect external devices
I. Please ensure that the amplifier and all equipment being connected are powered off.
II. Make sure that all of the connections are impedance and level matched with the amp inputs.
:
3.Connect the power cord and turn on the amplifier:
I. Please make sure that the power switch of the amplifier and its connected equipment are
turned off (in the OFF position).
II. Turn the master volume knob all the way down.
III. Connect the supplied power line to the AC IN interface.
IV. Plug the power cord in.
V. Turn on the connected equipments (computer, etc.) then turn on the amplifier and adjust levels.
SPK- SPK+

8
4. OPERATION
4.
I. Turn the volume all the way down, plug in the microphone and microphone cable to the amplifier.
II. Adjust the volume to approximately 30% of max.
III. Speak into the microphone and gradually turn up the volume until you reach the desired level.
Plugging in microphones:
5.Shutting down the system:
I.Turn the master volume knob all the way down.
II.Turn off the power switch of the amplifier. Afterwards, shutdown the connected audio sources.

9
5. TROUBLESHOOTING
Symptom Likely Cause
1. No power, no lights are lit on the amp.
1Power cord not fully connected
2. Power switch on front panel is not on
.
2. Inputs are connected, power light is on
but there is no sound.
3. The audio suddenly goes quiet
during normal operation.
1. Make sure temperature “PROT” light is not on
2. Check speaker wire continuity with a meter.
4. Low sound
5. Sound is distorted
3. Check fuse, it is possibly blown due to speaker short
1. Make sure source volume is up.
2. Make sure mixer volume is up.
3. Make sure master volume is up.
4. Make sure there is no speaker short.
5. Make sure speaker wires are all connected.
1. Improper taps are set on the speakers.
2. Improper speaker voltage switch position.
3. Source volume, or mixer volume is too low.
1. Source volume is too high.
2. Mixer volume is too high.
3. Check to see if the “CLIP” light is on - it shouldn’t be.
due to overheating.

6. APPLICATIONS
REAR PANEL CONNECTIONS
10
70V/
100V
OUTPUT
70V100V
COM COM COM
MIC3 MIC 2 MUTE
MIC 4/AUX 1EMC IN
AUDIO AUX2 AUX1
OUTPUT INPUT
L L R R
OPEN
CLOSE
PLAY STOP NEXTPREVIOUS
ON
OFF
POWER
Audio source equipment like CD/MP3 player
VOL
PLAY MSG
MIC
in
PLAY SIREN
REC in
ON
OFF
STANDB Y
PLAYALARM MODE RECORD
STOPSTART
Alarm signal generator
Speakers
AC power input
MIC

11
7. BLOCK DIAGRAM
MIC1 MIC2 MIC3 MIC4
EMC IN
AUX2AUX1
2-STAGE EQ BA SS TREBLE
LEVEL
120W
Protection circuit
LED display
Amplifier output
LEVEL LEVEL LEVEL LEVEL LEVEL
MUTE_MIC1
MUTE_ALL
Q2
GND
MUTE_ALL
Q1
GND
MUTE_MIC1
AUDIO OUT
Switchover between 70V and 100V
DC 24V inverter
power supply
Switching
power supply
Amplifier
module

12
8. SPECIFICATIONS
Input Sensitivity
Pre-output
MIC:5mV
AUX: 350mV
EMC: 775mV±40mV
±1mV
±20mV
AUDIO OUT:1V±50mV/100Ω
Model
Rated Power
SXR-120D
120W
Output Level 70V/100V
Mic Frequency Resp. Low frequency
High frequency
:±10dB at 100Hz；
:±10dB at 10KHz
SNR
THD
LED Indicators
Short-circuit Mode
Cooling Mode
Protection Mode
Frequency Response AUDIO OUT z～z
MIC：200Hz～16KHz（±3dB）
：20H 20KH （±3dB）
MIC ≥65dB; ≥70dB：Music:
THD+N≤0.1%
Short-circuit, no voltage
Air cooling
Overheat/Short-circuit
Voltage
Operation Temperature
Storage Temperature
Relative Humidity
+5 C +40 C~
-20 C +70 C~
<95%(No condensation)
Power Consumption
Dimension
Weight
484×295 44mm×
200W
3.6Kg
Music Frequency Resp. Low frequency
High frequency
:±10dB at 100Hz；
:±10dB at 10KHz
PROT, 70V, 100V, OL, CLIP, SIG & POWER
~110V 50Hz
~120V 50Hz
~110V 60Hz
~120V 60Hz

Over 40mm
44
48
484
44
436
44
295
6
70V/
100V
OUTPUT
70V100V
COM COM COM
MIC3 MIC 2 MUTE MIC 4/AUX 1EMC IN
AUDIO AUX2 AUX1
OUTPUT INPUT
L L
R R
9. DIMENSIONAL DIAGRAM
13
UNIT:mm
Over 40mm
Over 40mm
ON
OFF
POWER
MIC1 INPUT
PROT
MIC /4 AUX 1 AUX 2MIC 3
MIC 1 MIC 2 MASTER
100V
70V SIG
CLIP
OL
TREBLEBASS
10 0 10 0 10 0 10 0 10 0 10 0
ON
OFF
POWER
MIC1 INPUT
PROT
MIC /4 AUX 1 AUX 2MIC 3
MIC 1 MIC 2 MASTER
100V
70V SIG
CLIP
OL
TREBLEBASS
10 0 10 0 10 0 10 0 10 0 10 0
SXR-120D 70/100V
120W MIXER/AMP
4
SXR-120D 70/100V
120W MIXER/AMP

Version V1.1
1491 N. Kealy St.
Suite 8
Lewisville, TX 75057
www.roemtech.com PH: 972-221-3030 copyright 2018, ROEMTECH LLC
PUBLIC ADDRESS AMPLIFIER
SXR-120D MIXER/AMP