AUDAC EPA252 User manual

EPA152/252/502
User Manual
www.audac.eu

2
ADDITIONAL INFORMATION
This manual is put together with much care, and is as complete as could be on the
publication date. However, updates on the specifications, functionality or software may
have occurred since publication. To obtain the latest version of both manual and software,
please visit the Audac website @ www.audac.eu.

3
Index
Introduction 5
Precautions 6
Safety requirements 6
Caution servicing 6
EC Declaration of Conformity 6
Waste of Electrical and Electronic Equipment (WEEE) 7
Caution 7
Chapter 1: Pin connections and connectors 9
Connection standards 9
Chapter 2: Front & rear panel 10
Front panel overview 10
Front panel description 10
Rear panel overview 11
Rear panel description 11
Chapter 3: Connecting the amplifier 12
Input connections 12
Output connections 12
Connection modes 13
Chapter 4: Additional information 14
Technical specifications 14
Notes 16

4

5
Introduction
Dual channel Class-D amplifiers
The EPA series are energy efficient Class-D power amplifiers designed for a wide variation of
applications, ranging from standard stereo configurations to multi-zone distributed speaker
systems. They come available in various models with different output configuration and
power ratings.
An outstanding sound quality is combined with other known advantages of Class-D amplifiers
such as high energy efficiency. Automatic signal detection switches the amplifier to standby
mode when no input signal is detected. This makes the amplifier comply to international
energy and environmental requirement standards.
The compact size and lightweight design only requires a single 19” rackspace, while making
them suitable for both fixed rack and mobile applications. The convection cooled construction
requires only a minimum maintenance while guaranteeing high reliability.
The dual channel models of the EPA series are containing two individually controllable
channels with the possibility for bridging the outputs, merging their power to a single load.
They are featuring advanced protection circuitry which protects against DC malfunctioning,
short circuit, overheating and overload.
The signal input connections are implemented using balanced XLR connectors with link output
connectors, allowing linkthrough to other amplifiers. Loudspeaker outputs are connected
using both Speakon compatible and terminal block output connectors.

6
Precautions
READ FOLLOWING INSTRUCTIONS FOR YOUR OWN SAFETY
ALWAYS KEEP THESE INSTRUCTIONS. NEVER THROW THEM AWAY
ALWAYS HANDLE THIS UNIT WITH CARE
HEED ALL WARNINGS
FOLLOW ALL INSTRUCTIONS
NEVER EXPOSE THIS EQUIPMENT TO RAIN, MOISTURE, ANY DRIPPING OR SPLASHING
LIQUID. AND NEVER PLACE AN OBJECT FILLED WITH LIQUID ON TOP OF THIS DEVICE.
DO NOT PLACE THIS UNIT IN AN ENCLOSED ENVIRONMENT SUCH AS A BOOKSHELF
OR CLOSET. ENSURE THERE IS ADEQUATE VENTILATION TO COOL THE UNIT. DO NOT
BLOCK THE VENTILATION OPENINGS.
DO NOT STICK ANY OBJECTS THROUGH THE VENTILATION OPENINGS.
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 WHICH CONTAIN HIGH LEVELS 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
ONLY CONNECT THIS UNIT TO A MAINS SOCKET OUTLET WITH PROTECTIVE
EARTHING CONNECTION
THE MAINS PLUG OR APPLIANCE COUPLER IS USED AS THE DISCONNECT DEVICE, SO
THE DISCONNECT DEVICE SHALL BE READILY OPERABLE
EC DECLARATION OF CONFORMITY
This product conforms to all the essential requirements and further
relevant specifications described in following directives: 2014/30/EU
(EMC) and 2014/35/EU (LVD)
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)

7
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.
WASTE ELECTRICAL AND ELECTRONIC EQUIPMENT (WEEE)
The WEEE marking indicates that this product should not be disposed
with regular houshold waste at the end of its life cycle. This regulation
is created to prevent any possible harm to the environment or human
health.
This product is developed and manufactured with high quality materials
and components which can be recycled and/or reused. Please
dispose this product at your local collection point or recycling centre
for electrical and electronic waste. This will make sure that it will be
recycled on an environmentally friendly manner, and will help to protect
the environment in which we all live.

8

9
Chapter 1
Pin 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 signal input connections
Pin 1: Ground
Pin 2: Signal +
Pin 3: Signal -
For balanced signal link-through connections
Pin 1: Ground
Pin 2: Signal +
Pin 3: Signal -
Wire up the system
The wiring of the system must be done according to the following rules, to guarantee a
proper functioning of the system in all circumstances.
1. Speaker cable for amplified outputs:
Minimum 2 x 1.5 mm²
If distance > 15m: 2 x 2.5 mm²)
2. Audio signal inputs (inputs & signal linkthrough outputs)
Must be connected with high-quality audio cable and high-quality
connectors

10
Chapter 2
Front & rear panel
Front panel overview
ON
100
PROTECT
CLIP
SIGNAL
100
PROTECT
CLIP
SIGNAL EPA502
Front panel description
Volume control knobs:
These volume control knobs allow level adjustment for each individual channel.
Indicator LED’s:
These LED’s indicate the operation of the corresponding amplifier channel. A signal indicator,
clip indicator and protect indicator are available for each channel.
The signal indicator illuminates in green colour when the signal level exceeds the -20 dB level.
The clip indicator illuminates in yellow colour when the channel is working at maximum level.
To ensure the best signal-to-noise ratio, illumination of this indicator should only occur
at peak levels. When it illuminates frequently, the channel output will be overdriven and a
distorted ‘clipping’ sound occurs on the output.
The protect indicator illuminates in red colour when any overload, thermal overheating or
other fault is detected. It also illuminates for several seconds when powering on the amplifier
and slowly fades out when switching off the amplifier. When the protect LED is illuminated,
no signal will be available on the output.
Power switch with LED:
A power switch allows to turn the amplifier on and off. The indicator LED next to the power
switch indicates the current status of the amplifier. When operational, it illuminates in blue
colour. When switched to standby (energy-saving) mode, the power LED will illuminate in
orange colour. The amplifier switches automatically to standby mode when no input signal
is available for about 30 seconds and instantly switches back to operation when any signal
is detected.

11
Rear panel overview
Bridge Parallel
Stereo
MODE
CH 1
AC Input 230V 50/60Hz, 220W Fuse: T10AL/250V
CH 2
Speakon 2 Speakon 1
CH 1:
Bridge :
CH 2:
Speakon 1
Bridge
CH 1
SPEAKER OUTPUT
INPUTLINK
CH 2
INPUTLINK
CH 2:
Speakon 2
EPA502
AUDAC
PROFESSIONAL POWER AMPLIFIER
Rear panel description
AC Power inlet with fuse:
The mains power supply has to be applied to this AC power inlet. The connection is made
by an IEC C14 power connector and is fitted with a fuse. When replacing the fuse, make
sure that the value of the replacement fuse matches the value of the original fuse. (EPA152:
T5AL/250V - EPA252: T6.3AL/250V - EPA502: T10AL/250V )
Loudspeaker connections:
The loudspeaker output connections for each channel are implemented using both Speakon
compatible and terminal block connectors. Depending of the application requirements, the
appropriate connection method can always be used. A detailed description for connecting
loudspeakers in the most appropriate way for each application can be found in the next
chapter ‘Connecting the amplifier’.
Input connections:
The signal input connections are implemented using balanced XLR connectors with link
output connectors. Each channel is provided with an individual input connection whereto
the signal coming from the audio source of pre-amplifier shall be fed, while the link output
connectors can be used for linkthrough to other amplifiers.
Operation mode switch:
An operation mode switch allows switching between stereo, bridge and parallel mode.
Bridge Parallel
Stereo
MODE
It is default configured in stereo mode (center position) whereby each amplifier channel is
fed with an individual input signal. In bridge mode (left position), the power of both channels
is merged for delivering double power to a single load. In parallel mode (right position), the
input is linked, feeding the identical signal to both channels.

12
Chapter 3
Connecting the Amplifier
NOTE
Make sure the power is switched OFF when any change is made to the connections of
the amplifier.
Input connections
The signal input connections are implemented using balanced XLR connectors with link
output connectors. Each channel is provided with an individual input connection whereto
the signal coming from the audio source of pre-amplifier shall be fed, while the link output
connectors can be used for linkthrough to other amplifiers.
Bridge Parallel
Stereo
MODE
CH 1
INPUTLINK
CH 2
INPUTLINK
An operation mode switch allows switching the channels between stereo, bridge and parallel
mode.
Output connections
The loudspeaker output connections are implemented using both Speakon compatible and
terminal block connectors. Depending of the application requirements, the appropriate
connection method can always be used.
CH 2
Speakon 2 Speakon 1
CH 1:
Bridge :
CH 2:
Speakon 1
Bridge
CH 1
SPEAKER OUTPUT
CH 2:
Speakon 2
The ‘Speakon 1’ output connector carries signals for both both channels, allowing connection
for both channels through a single 4-core cable or bridge mode connections.
ATTENTION
Do not make any direct connection with line transformers on the loudspeaker outputs
of the amplifier. When using in combination with line transformers units, make sure the
used transformers are designed for being used in combination with Class-D amplifiers
(containing integrated decoupling network).

13
Connection modes
Stereo (2-Channel) mode:
In 2-Channel mode, each channel will be driven by a separate input signal with individual
loudspeaker(s) connected to it. The operation mode switches shall be in stereo mode (center
position). If both channels shall be fed with identical signals, the parallel mode (right position
of operation mode switch) can be used. Loudspeaker cabling shall be connected to the +
and - terminals for each individual loudspeaker output connection.
Channel 1Channel 2
Input 1 Input 2
Bridge Parallel
Stereo
MODE
CH 1
AC Input 230V 50/60Hz, 220W Fuse: T10AL/250V
CH 2
Speakon 2 Speakon 1
CH 1:
Bridge :
CH 2:
Speakon 1
Bridge
CH 1
SPEAKER OUTPUT
INPUTLINK
CH 2
INPUTLINK
CH 2:
Speakon 2
EPA502
AUDAC
PROFESSIONAL POWER AMPLIFIER
Bridged (mono) mode:
In bridged (mono) mode, both output channels will be merged for delivering double power to
a single load. The bridged configuration can be enabled through placing the operation mode
switches in bridge mode (left position). The input connections of channel 1 shall be used
while loudspeakers are connected between + and - terminals of both separate channels.
Input
Bridge Parallel
Stereo
MODE
CH 1
AC Input 230V 50/60Hz, 220W Fuse: T10AL/250V
CH 2
Speakon 2 Speakon 1
CH 1:
Bridge :
CH 2:
Speakon 1
Bridge
CH 1
SPEAKER OUTPUT
INPUTLINK
CH 2
INPUTLINK
CH 2:
Speakon 2
EPA502
AUDAC
PROFESSIONAL POWER AMPLIFIER
Channel 1+2

14
Chapter 4
Additional information
Technical specifications
RMS Output power EPA152 4 Ohm stereo 2 x 150 W
8 Ohm stereo 2 x 80 W
8 Ohm bridge 1 x 300 W
EPA252 4 Ohm stereo 2 x 250 W
8 Ohm stereo 2 x 130 W
8 Ohm bridge 1 x 500 W
EPA502 4 Ohm stereo 2 x 500 W
8 Ohm stereo 2 x 300 W
8 Ohm bridge 1 x 1000 W
Frequency response 20 Hz - 20 kHz
Signal to Noise ratio > 90 dB
Total Harmonic Distortion + Noise < 0.1%
Crosstalk > 70 dB
Inputs Type Balanced line
Connectors Female XLR
Male XLR linkthrough
Impedance 12 k Ω
Sensitivity 0 dB (1 V RMS)
Outputs Type Loudspeaker output
Connectors Speakon compatible
2-pin terminal block ~ 5.08 mm pitch
Controls Front panel control
Indicators Power (& standby)
Protect
Clip
Signal
Cooling system Convection cooled
Amplifier technology Class-D
Power supply Type Switching mode
Range EPA152 100-240V AC - 50/60 Hz
EPA252 100-240V AC - 50/60 Hz
EPA502 230-240V AC - 50/60 Hz

15
NOTE
The power supply range for EPA502 is default configured for use on 230-240V AC -
50/60 Hz (EU) mains network. Internal modification allows this model being used on
110-120V AC - 50/60 Hz (US) mains network. Contact your local service center for
more information.
Power consumption Standby EPA152 0.8 W
EPA252 0.8 W
EPA502 0.7 W
Idle EPA152 24.1 W
EPA252 19.2 W
EPA502 26.1 W
1/8 Rated power EPA152 69 W
EPA252 98.1 W
EPA502 183 W
1/3 Rated power EPA152 145 W
EPA252 224 W
EPA502 426 W
Dimensions (W x H x D) 482 x 44 x 330 mm
Unit height 1 HE
Weight EPA152 4.1 Kg
EPA252 4.4 Kg
EPA502 4.7 Kg

16
Notes