AUDAC ATU44MK2 User manual

ATU44MK2
User Manual
www.audac.eu

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Index
Introduction 4
Precautions 5
Safety requirements 5
Caution servicing 6
EC Declaration of Conformity 6
Waste of Electrical and Electronic Equipment (WEEE) 6
Chapter 1: Connections and connectors 8
Connection standards 8
Chapter 2: Overview ATU44MK2 9
Block diagram 10
Chapter 3: Connections 10
Chapter 4: Technical specifications 11

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Introduction
Universal input adapter unit
The ATU44MK2 is a universal input adapter unit for conversion between various audio
level signals, offering a wide variety of connection and extention possibilities to audio
systems. The speaker level input features various tappings for 100V, 70V, 50V and 33V
audio levels, while a balanced line input allows conversion between balanced and/or
unbalanced line level audio signals.
A typical application example is the conversion of any loudspeaker level audio signal to
balanced or unbalanced line level signals. Any type of loudspeaker level signal can get
applied to its input. This can be useful for expansion of any constant voltage distributed
audio system and feeding the transformed output to an additional amplifier. Another
typical application is connection of recording equipment on loudspeaker lines.
Using the galvanic isolation between all the in & outputs, it can be used as an audio
isolation solution, solving hum and buzz problems caused by ground loops.
The front panel switch allows input signal selection between line or loudspeaker level
input, while all inputs are connected using terminal block connectors. The line output is
connected using a male XLR connector.
A variety of optionally available mounting brackets are allowing desk, closet or 19”
equipment rack installation.

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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.
• THE INSTALLATION, CONNECTION AND CONFIGURATION OF THE DEVICE
SHOULD BE DONE BY QUALIFIED TECHNICIANS

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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.
CAUTION
The symbols shown are internationally recognized symbols that warn about potentional
hazards of electrical products. The lightning flash with arrowpoint in an equilateral
triangle means that the unit contains dangerous voltages. The exclamation point in
an equilateral triangle indicates that it is necessary for the user to refer to the users
manual.
These symbols warn that there are no user serviceable parts inside the unit. Do not
open the unit. Do not attempt to service the unit yourself. Refer all servicing to qualified
personnel. Opening the chassis for any reason will void the manufacturer’s warranty.
Do not get the unit wet. If liquid is spilled on the unit, shut it off immediately and take
it to a dealer for service. Disconnect the unit during storms to prevent damage.

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ADDITIONAL INFORMATION
This manual is put togheter with much care and effort and is as complete as could be
on the publication date. However, updates on the specifications and functionality may
have occurred since publication. To obtain the latest version of this manual please
visit the Audac website @ www.audac.eu.

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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.
XLR:
For balanced line output connections
Pin 1: Ground
Pin 2: Signal +
Pin 3: Signal -
ATTENTION
Make sure the power of the device and other connected devices is switched off, before
any connections or wiring adjustments are being made. Disregarding this rule can lead
to electrical shocks and/or permanent damage of the equipment.

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Chapter 2
Overview ATU44MK2
The panel of the ATU44MK2 contains all connections for the loudspeaker level and line
in & outputs, accompanied with an input selector switch.
1) Loudspeaker input:
The loudspeaker input is implemented using a 5-pin terminal block connector with
various tappings for 100V, 70V, 50V and 33V audio levels. Depending of the available
audio level, the input signal shall get connected to the appropriate tappings.
2) Balanced line level input:
The balanced line level input is implemented using a 3-pin terminal block connector.
Line level input signals (balanced or unbalanced) shall be connected to this terminal.
3) Input selector switch:
This switch allows selection of the input signal between line level (left position) or
loudspeaker level (right position) inputs.
4) Balanced line level output:
The balanced and galvanic isolated output signal connection is available on the female
XLR connection. The level of this output connection matches line level (depending of
matching input levels), allowing it to be fed directly to any line level input on amplifiers
or pre-amplifiers.

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Block diagram
Chapter 3
Connections
1) Connection of constant voltage loudspeaker signals:
The ATU44 can be used for conversion of a constant voltage loudspeaker level signal
as mainly used in distributed public address audio systems, into a balanced line level
audio signal. Depending of the line voltage (100V, 70V, 50V or 33V), the correct terminals
of the loudspeaker input (5-pin terminal block) connector shall be used. The line level
output (available on the XLR connector) can then be fed directly to any line level input
on amplifiers or pre-amplifiers. Make sure the input selector switch is in 100V (right)
position.

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2) Connection of low impedance loudspeaker signals:
The ATU44 can be used for conversion of a low impedance (8Ω) loudspeaker level
signal into a balanced line level audio signal. Depending of the amplifier power, the
corresponding terminals of the loudspeaker input (5-pin terminal block) connector
shall be used. Below table gives an overview of the matching voltage tappings for
various amplifier power:
Voltage tapping Amplifier power
33 Volt
50 Volt
70 Volt
100 Volt
< 150 Watt amplifier power (@ 8 Ohm)
150 Watt < 300 Watt amplifier power (@ 8 Ohm)
300 Watt < 600 Watt amplifier power (@ 8 Ohm)
> 600 Watt amplifier power (@ 8 Ohm)
The line level output (available on the XLR connector) can then be fed directly to any
line level input on amplifiers or pre-amplifiers. Make sure the input selector switch is
in 100V (right) position.
3) Connection line level input signals:
The ATU44 can be used as a galvanic isolator between line level input signals allowing
it for being used as an audio isolation solution, solving hum and buzz problems caused
by ground loops. The line level input shall be applied to the 3-pin line level terminal
block input connector.
For balanced input signals, Sig+ (XLR pin 2) shall be connected to the ‘+’ terminal, Sig-
(XLR pin 3) shall be connected to the ‘-’ terminal, and GND (XLR pin 1) shall be connected
to the ‘GND’ terminal. For unbalanced input signals, the signal shall be connected to the
‘+’ signal and the ‘GND’ shall be connected to the ‘-’ terminal.
The line level output (available on the XLR connector) can then be fed directly to any
line level input on amplifiers or pre-amplifiers. Make sure the input selector switch is
in Line (left) position.

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Chapter 4
Technical specifications
Inputs Type 100V, 70V, 50V, 33V audio inputs
Connectors 5-pin terminal block (5.08 mm pitch)
Type Balanced line level audio input
Connectors 3-pin terminal block (5.08 mm pitch)
Impedance 600 Ohm
Outputs Type Balanced line level audio output
Connectors Male XLR
Impedance 600 Ohm
Dimensions (W x H x D) 108 x 44 x 165 mm
Weight 0.45 Kg
Packaging Carton box
Shipping weight & Volume 0.77 Kg - 0.0078 Cbm
Compatible devices WLI18 Wall line input unit
WMI18 Wall microphone input unit
Optional accessories MBS1xx Mounting brackets