AUDAC AMP20 MK2 User manual

AMP20MK2
User Manual
www.audac.eu

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Index
Introduction 5
Precautions 6
Safety requirements 6
Caution servicing 7
EC Declaration of Conformity 7
Waste of Electrical and Electronic Equipment (WEEE) 7
Chapter 1: Connections and connectors 9
Connection standards 9
Chapter 2: Overview AMP20MK2 11
Front panel 11
Rear panel 12
Chapter 3: AMP20MK2 Quick start guide 14
Connecting the AMP20MK2 14
Configuring the AMP20MK2 15
Ready 15
Chapter 4: Technical specifications 16

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Introduction
Mini Stereo Power Amplifier
The AMP20 MK2 is a Mini Stereo Power Amplifier with a power rating of 2 x 15 Watt,
which lends itself perfectly to small speaker systems requiring compact and economical
audio solutions. It offers the ideal solution for applications such as classrooms, offices
and meeting rooms where a small amount of speakers are required.
The compact size and very high efficiency makes it perfectly suited to be hidden in a
closet, on a false ceiling or mounted under a desk or table.
The combination of the stereo balanced line and microphone input make it perfectly
suited for applications where it should be used in combination with projection screens
and video sources while a microphone is connected. Two gain potentiometers make it
possible to control the sensitivity and balance between music and speech, while a switch
allows bridging of the output channels to obtain one channel with merged output power.
A remote wall mixer can be connected for applications where local mixing of the inputs
is desirable, while large distances can be covered between the source and amplifier
using simple CAT5 twisted pair cabling. The volume controller input allows connection
of an additional wall controller for overall volume control.
The Class-D Amplifier technology, standby mode and included switching power supply
makes this device compliant to Energy Star 3.0 and other strict energy efficiency and
environmental requirements.

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Precautions
READ FOLLOWING INSTRUCTIONS FOR YOUR OWN SAFETY
• ALWAYS KEEP THESE INSTRUCTIONS FOR FUTURE REFERENCE. NEVER
THROW THEM AWAY
• ALWAYS HANDLE THIS UNIT WITH CARE
• CLEAN ONLY WITH DRY CLOTH
• HEED ALL WARNINGS AND FOLLOW ALL INSTRUCTIONS
• NEVER EXPOSE THIS EQUIPMENT TO RAIN, MOISTURE, ANY DRIPPING OR
SPLASHING LIQUID. NEVER PLACE AN OBJECT FILLED WITH LIQUID ON TOP
OF THIS DEVICE
• DO NOT INSTALL THIS UNIT NEAR ANY HEAT SOURCES SUCH AS RADIATORS
OR OTHER APPARATUS THAT PRODUCE HEAT
• DO NOT PLACE THIS UNIT IN ENVIRONMENTS WITH A HIGH LEVEL OF DUST,
HEAT, MOISTURE OR VIBRATION
• THIS UNIT IS DEVELOPED FOR INDOOR USE ONLY. DO NOT USE IT OUTDOORS
• PLACE THE UNIT ON A STABLE BASE OR MOUNT IT IN A STABLE RACK
• ONLY USE ATTACHMENTS & ACCESSORIES SPECIFIED BY THE
MANUFACTURER.
• UNPLUG THIS APPARATUS DURING LIGHTNING STORMS OR WHEN UNUSED
FOR LONG PERIODS OF TIME
• CAREFULLY CHECK THE UNIT’S CONDITION AFTER UNPACKING.
IF THERE IS ANY DAMAGE TO THE CARTON BOX OR THE UNIT ITSELF,
INFORM YOUR VENDOR IMMEDIATELY.
• ONLY CONNECT THIS UNIT TO A MAINS SOCKET OUTLET WITH PROTECTIVE
EARTHING CONNECTION
• THE INSTALLATION, CONNECTION AND CONFIGURATION OF THE DEVICE
SHOULD BE DONE BY QUALIFIED TECHNICIANS

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CAUTION
• USE CABLES OF THE RIGHT GAUGE FOR CONNECTING LOUDSPEAKERS TO
THE AMPLIFIED OUTPUTS
• USE CABLES WITH CLEAR COLOUR CODING INDICATING THE POLARITY AND
MAINTAIN THE SAME POLARITY THROUGHOUT THE WHOLE SYSTEM.
• ONLY USE THE CORRECT LOAD IMPEDANCE (MIN 4 OHM) WHEN
CONNECTING LOUDSPEAKERS TO THE AMPLIFIED OUTPUTS. EXCEEDING
THESE LIMITS COULD CAUSE FIRE OR OTHER FAILURES.
• DO NOT CONNECT INDUCTIVE LOADS DIRECTLY TO THE AMPLIFIED OUTPUTS
• AVOID ELECTRIC SHOCKS: SWITCH OFF THE AMPLIFIER WHEN CONNECTING
CAUTION - SERVICING
This product contains no user serviceable parts. Refer all servicing
to qualified service personnel. Do not perform any servicing
(unless you are qualified to do so.)
EC DECLARATION OF CONFORMITY
This product conforms to all the essential requirements and
further relevant specifications described in following directives:
2004/108/EC (EMC) and 2006/95/EC (LVD)
WASTE ELECTRICAL AND ELECTRONIC EQUIPMENT (WEEE)
The WEEE marking indicates that this product should not be
disposed with regular household waste at the end of its product
life. This regulation is created to protect both the environment
and human health.
This product is developed and manufactured with high quality
materials and components which can be recycled and/or reused.
Please dispose of this product at your local collection point or
recycling centre for electrical and electronic waste. Do this to
make sure that the product is recycled in an environmental friendly
way, and help to protect the environment in which we all live.

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Chapter 1
Connections and connectors
CONNECTION STANDARDS
The in- and output connections for AUDAC audio equipment are performed
corresponding to international wiring standards for professional audio equipment.
Cinch (RCA):
For unbalanced line input connections
Tip: Signal Sleeve: Ground
White: Left Red: Right
XLR:
For balanced input connections
Pin 1: Ground
Pin 2: Signal +
Pin 3: Signal -
3-Pin Euro-Terminal Block:
For balanced input connections
Left: Signal - (XLR Pin 3)
Center: Signal + (XLR Pin 2)
Right: Ground (XLR Pin 1)
For balanced input connections:

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For unbalanced input connections:
REMOTE WALL MIXER RJ45 (Audio, +8V DC, -8V DC):
For connection to Remote Wall Mixers (Audio Input & Mixing)
Pin 1 White-Orange AUDIO Left +
Pin 2 Orange AUDIO Left -
Pin 3 White-Green + 8V DC
Pin 4 Blue - 8V DC
Pin 5 White-Blue GND
Pin 6 Green GND
Pin 7 White-Brown AUDIO Right +
Pin 8 Brown AUDIO Right -
VOLUME CONTROLLER RJ45:
For connection to wall mounted volume controllers (Overall volume control)
Pin 1 White-Orange N/C
Pin 2 Orange N/C
Pin 3 White-Green - 8 V DC
Pin 4 Blue 0 ~ - 8V Variable in
Pin 5 White-Blue GND
Pin 6 Green GND
Pin 7 White-Brown N/C
Pin 8 Brown N/C
ATTENTION
The twisted pair cabling must always be ‘straight’. In case
of self made cabling, it must be wired as described above,
to make the system work properly.

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Chapter 2
Overview AMP20MK2
Front panel
The front panel of the AMP20MK2 contains all the control and indicator functions.
Two gain control potentiometers are provided with which the gain of the line and
microphone inputs can be regulated separately and the balance between the music
and speech can be set.
A slide switch provides the possibility to switch the amplifier between Stereo and
Mono / Bridge mode. If this switch is set to stereo, the output will be stereo. If its set
to Mono / Bridge, the Left and Right channels will be summed to a dual-mono output.
Three indication LED’s for ‘ON / STANDBY’, ‘SIGNAL’ and ‘CLIP’ indicate the operation
mode of the amplifier. The ‘ON / STANDBY’ LED will turn green when the device is
switched ON and running. When no signal with a sufficiently high level is detected
for a certain period of time, it will switch to standby mode and this LED will turn
orange. The ‘SIGNAL’ LED will turn green when a signal with a sufficiently high level
is detected and the ‘CLIP’ LED will start blinking when the signal reached the clipping
level and the internal limiter starts working.

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All necessary connections of the AMP20 MK2 are provided at the backside of the device.
An overview and explanation of all the connectors and possibilities is given below.
1) 24 Volts power connector:
The 24 Volts power supply connection is provided on the left side of the AMP20MK2’s
rear panel. The included power supply (PSD241) should be connected to the terminal
block connectors. Pay attention to the polarity when connecting the power supply.
2) Loudspeaker output:
The loudspeakers should be connected to the 4-pins ‘AMP OUT’ Terminal Block
connector. Depending on the position of the Stereo and Mono / Bridge switch on
the front panel, the corresponding audio output will be available here. When used
in Stereo mode, the left loudspeaker(s) should be connected to the two leftmost
terminals and the right loudspeaker(s) should be connected to the two rightmost
terminals. When used in Bridge mode, the loudspeaker(s) should be connected to the
two outer terminals.
3) Remote wall mixer and Volume controller connections:
Two RJ45 connectors are provided for connecting Remote wall mixers and external
overall volume controllers. The connections on these extension ports should be made
by using a simple CAT5 twisted pair (or better) cable in a straight pinout configuration.
The pinout and colour coding is described on Chapter 1 of this instruction manual.
The remote wall mixer connection carries the supply voltage to the wall input unit and
a stereo differential audio signal from the wall input unit to the amplifier.
Rear panel

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The audio signal coming from the remote wall mixer will be proportionally mixed with
the direct line and microphone inputs.
The volume controller connection carries a negative supply voltage to the external
volume controller and has an input for a variable negative voltage. Depending on this
voltage, the overall volume will be regulated. When no external volume controller is
connected, the overall volume of the device will be defaulted to its maximum.
4) Balanced Stereo Line and Microphone inputs:
The balanced stereo line and microphone input are performed using 3-pins terminal
block connectors.
All different kinds of balanced and unbalanced line level audio sources can be
connected to the line inputs. Some examples are CD & MP3 players, Tuners, Laptops,
DVD players, ...
The microphone input provides the possibility of connecting any kind of microphone
without phantom power requirement.

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Chapter 3
AMP20MK2 Quick start guide
This chapter guides you through the setup process for a basic AMP20MK2 project whereto
a line level audio source and a microphone are connected directly . An external volume
controller and remote wall mixer are installed remotely.
Line Level
Music Source
Stereo Audio
Mic CAT5
CAT5
Microphone
VC3008/4008
WP523
AUDAC
LINE IN
MIC IN
Overview of the AMP20MK2 setup
Connecting the AMP20MK2
1) Connecting audio inputs
Connect all your audio sources (CD & MP3 players, tuners, microphones, ... ) to the
audio inputs of the AMP20MK2. All the direct audio inputs are performed using 3-pins
terminal block connectors. For more information about the connections and wiring
pinout, check Chapter 1 of this manual.

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2) Connecting audio outputs
This suggested application uses a total of four loudspeakers. The AMP20MK2 contains
two speaker outputs (stereo) meaning that two speakers should be connected on
every amplified output. The speakers must be connected in parallel and the load on
each amplifier output channel should be 4 Ohm or higher.
3) Connecting the external units
The external (optional) wall volume controllers and remote wall mixers should be
connected to the corresponding RJ45 connector ports. The connections should
be made by using simple CAT5 twisted pair (or better) cabling in a straight pinout
configuration. The maximum cable length between the external units and the
AMP20MK2 may not exceed a total cable length of 100 meters.
4) Connecting the power supply
The included power supply should be connected to the 2-pins Euro Terminal block
connector. Watch the polarity when connecting the power supply.
Configuring the AMP20MK2
1) Adjusting the input sensitivity & volume
The configuration of the AMP20MK2 only includes the sensitivity adjustment of the
inputs and the overall volume regulation. The sensitivity of the inputs can be regulated
by the two potentiometers on the front panel of the AMP20MK2. The correct regulation
depends on the signal level of the connected sources and the requirements for each
specific application. The regulation should be done experimentally, making a good
balance between the music signal from the audio source and the speech from the
microphone.
The line and microphone level signal coming from the remote wall mixer is mixed
locally and the balance can be set using both push-lock potentiometers. The output
level can be set using the big volume dial. This signal is mixed with the direct line and
microphone inputs at equal levels.
After all sensitivity settings have been made, the overall volume control can be done
using the VC3008/4008 volume controller.
Ready
Your system is now ready for use.

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Chapter 4
Technical specifications
Inputs Type Stereo Balanced Line
Connectors 2 x 3-pins Euro Terminal Block ~ 3.81 mm
Impedance 20 k Ohm
Sensitivity - 12 dBV ~ +10 dBV
Type Balanced Microphone
Connectors 3-pins Euro Terminal Block ~ 3.81 mm
Impedance 47 k Ohm
Sensitivity - 34 dBV ~ -18 dBV
Output Type Stereo Loudspeaker Output
Connectors 4-pins Euro Terminal Block ~ 5.08 mm
Impedance Min Load of 4 Ohm
Power 2 x 7.5 Watt @ 8 Ohm Stereo
2 x 15 Watt @ 4 Ohm Stereo
1 x 30 Watt @ 8 Ohm Bridge
THD+N < 0.1 %
Crosstalk - 75 dB
Signal / Noise ratio > 95 dB
Power consumption Standby 0.8 Watt
Nominal (1/8 MUP) 5.3 Watt
Absolute Max 35 Watt
Efficiency 1/8 MUP 70%
MUP 87%
Cooling Passive
Protection Over-Heat
Short circuit
Limiter
Auto Power Down Minimum signal -46 dB
Timing Max 90 Seconds

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Power supply 24V DC
PSD241 switching power supply included
100 ~ 240V AC / 47~63 Hz
NOTE: ‘MUP’ stands for Maximum Undistorted Power
Dimensions (W x H x D) 108 x 44 x 164 mm
Weight 0.80 Kg
Packaging Carton box
Shipping weight & Volume 1.12 Kg - 0.0078 Cbm
Optional Accessories VC3008/4008 Remote Volume controller
WP523 Remote Wall Mixer
MBS200 Mounting Bracket
CLA832 RCA / Cinch to Terminal Block cable
CLA835 XLR Female to Terminal Block cable
TR3030 100V Line Transformer 30 Watt

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Notes

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Notes

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Notes