Altair A3.5 User manual

A3.5,7,11
PROFESSIONAL POWER AMPLIFIERS
ADVANTAGE SERIES
NOTICE: PIN 2+
OWNERS MANUAL
EQUIPOS EUROPEOS ELECTRÓNICOS, S.A.L
Avda. de la Industria, 50. 28760 TRES CANTOS-MADRID (SPAIN).
34-1-804 32 65 34-1-804 43 58 [email protected]
www.altairaudio.com

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
CONTENTS
1. INTRODUCTION 3
2. SWITCHES, INDICATORS, ATTENUATORS AND CONNECTORS 4
FRONT PANEL 4
REAR PANEL 4
3. WORKING PRECAUTIONS 5
4. INSTALLATION 5
UNPACKING 5
MOUNTING 6
CHANGING THE FUSE 6
CONNECTING TO THE MAINS 7
INPUT CONNECTION 7
UNBALANCED INPUT 8
BALANCED INPUT 9
OUTPUT POWER CONNECTION. MODES OF OPERATION 9
STEREO MODE OPERATION 10
BRIDGE MODE OPERATION 11
EARTH LINK 11
5. OPERATION 12
POWER UP 12
INPUT ATTENUATORS 12
CLIP INDICATORS (INPUT SIGNAL OVERLOAD) 12
SIGNAL INDICATORS 13
ON/PROTECT INDICATORS 13
FAN 14
LOAD IMPEDANCES 14
MAINTENANCE 14
AMPLIFIER CONDITIONS 14
6. SPECIAL OPERATIONS 15
INPUT SENSITIVITY/GAIN ADJUST 17
LIMITER ON/OFF 17
CHANGING THE MAINS VOLTAGE 18
7. DISTRIBUTED SYSTEMS APPLICATION (PUBLIC ADDRESS) 19
8. OPTIONAL CROSS-OVER CARD 19
9. TECHNICAL SPECIFICATIONS 20
10. GRAPHS 21
11. WARRANTY 22

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
1. INTRODUCTION
Congratulations on your purchase of the ALTAIR power amplifier ADVANTAGE series. Our
dilated experience in the design and manufacture of audio power amplifiers has led us to carry out a
series of general purpose bipolar power amplifiers of great performances.
There is a lot the characteristics that make of the ALTAIR power amplifiers ADVANTAGES series,
one of the most highlighted of the audio professional market, here enumerated some:
Multiple protection
Has improved the circuits of DC output protection by relay. Guiding directly the power
transistors output to the loudspeakers binding post has improved several qualities of the signal
quality, the damping factor and the global reliability.
Equally, the conventional thermal switches (based on contacts) has been substituted of the
power modules by solid state sensors whose information completes the double condition of speed
fan control and discharge the thermal protection.
All the protection situations are displayed in the power amplifier front panel.
Clipping circuit limiter
Since most of the damage caused to loudspeakers, and even to the power amplifiers, is
normally the result of the permanence of the power unit during long periods of time in clipping,
it is necessary to have limiter mechanisms that assure their reliable operation.
For this purpose, all the ADVANTAGE series power amplifiers has a "soft-clipping" circuit that
acts on the output power by comparing the input and output signals. Once it detects a distortion or
other noticeable cut, it stabilises the integrity of the output signal thereby avoiding overloading and
saturation levels that might damage the system. This limiter effect is switchable on or off internally.
Under control
The conception of the new loudspeakers, especially the uses for low frequencies is based on
that the amplifiers that govern them behave as ideal voltage amplifiers, is say with zero output
impedance. The ADVANTAGE series approaches to this value nearly zero presenting a damping
factor better than 300 what redounds in a perfect control of the loudspeaker voice coil position along
their excursion.
Naturally, you want to use your power amplifier just now, but before beginning is important
that you read this manual. This manual will help you to install and use your new power amplifier. It is
very important that you read it carefully, mainly the paragraphs marked as NOTE, PRECAUTION and
DANGER, for your security.
Save the original packing, you can re-use it to transport the power amplifier. NEVER SHIP THE
POWER AMPLIFIER WITHOUT THE ORIGINAL PACKING.

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
2. SWITCHES, INDICATORS, ATTENUATORS AND CONNECTORS.
These are the switches, indicators, attenuators and connectors that you could find in your
power amplifier. The description and explanation of each one, you will find it in the corresponding
section.
FRONT PANEL:
INPUT ATTENUATOR. COOLING VENTS
INPUT SIGNAL OVERLOAD INDICATOR.
SIGNAL INDICATOR.
TURN ON / PROTECT INDICATOR.
POWER SWITCH.
REAR PANEL:
BINDING POST. COOLING VENTS
FUSE HOLDER.
MAINS CORD.
0
1
11
A
CLIP SIGNAL ON/PROTCLIP SIGNAL ON/PROT
CH-2CH-1
-15
-30
-oo 0
-20
-3
-9
dB
-15 -20
-30
-oo 0
-3
-9
dB
-15
CLIP
SIGNAL
ON/PROT
0
1

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
EARTH LINK SWITCH.
INPUT SIGNAL CONNECTOR XLR-3-31.
STEREO/ BRIDGE SWITCH.
XLR-3-32 OUTPUT SIGNAL CONNECTOR.
(ONLY WITH THE OPTIONAL CROSSOVER CARD FITTED).
INPUT SIGNAL SELECTOR FOR EACH CHANNEL.
(ONLY WITH THE OPTIONAL CROSSOVER CARD FITTED).
3. WORKING PRECAUTIONS
The manufacturer cannot be held responsible for any damage that is incurred by not using the
power amplifier in compliance with the warranty or working precautions.
DANGER: High voltage inside the amplifier. ! Do not open !. The power amplifier doesn't
contain parts that can be repaired by the user. The power amplifier could have electric
power stored in their interior even disconnected it from themains.
CAUTION: Protect the power amplifier from the rain and moisture. Ensure that no
objects or liquids enter it. If liquid is spilled into the power amplifier, disconnect the power
amplifier from the mains and consult aqualified service technician.
Don't place the power amplifier close to sources of heat. Also make sure that the front and the rear
panel there are free of obstructions, since the fan could not work properly and cause the thermal
protection work.
DANGER: The power amplifier output connectors could have high voltage. Make sureof turning off
the power amplifier before handling on these output connectors.
4. INSTALLATION
UNPACKING
Before leaving from factory, each power amplifier was carefully inspected and tested. Unpack
and inspect the power amplifier for any damage that may have occurred during shipment. If any
damage is found, doesn't connect the power amplifier to the mains, notify the salesperson
immediately, because the unit must be inspected by a qualified service technician.

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
Save the original packing, you could use if you need to transport the power amplifier. NEVER
SHIP THE POWER AMPLIFIER WITHOUT IT'S ORIGINAL PACKING.
MOUNTING
It is always advisable to mount the power amplifiers in rack, either for mobile or fixed
installations, for protection, safety, aesthetics, etc.
The ADVANTAGE series power amplifiers are designed for standard 19" rack mounting, and
occupy 2u high rack space.
Due to the weight of the unit, it should be securely fastened at the front and the back of the
cabinet. If the racks are carriage ones, it is advisable that have trays in order to allow the power
amplifier to rest on its base and in an elastic cradle, if possible. It is advisable, leave a separation
space between amplifiers and otherunits in order to facilitate its cooling, upon mounting the
amplifier in a rack.
In the mounting, either fixed or in rack, the cooling vents placed in the front and rear panel
should be free, so that the air circulates freely, and the amplifier could have a better heat
dissipation. In the same way, make sure that there are no heat sources near the front cooling vent,
because the fan exhaust cool air through thisvent.
CHANGING THE FUSE
The power amplifiers are designed to work with slow blow type fuses of 6x32, whose values
in order to work with a mains voltage of 230V 50-60 Hz or 115V 50-60 Hz. are specified in the
following list:
MODEL FUSE (230V. 50-60 Hz) FUSE (115V. 50-60 Hz)
A3.5 T5A. T8A.
A7 T6A. T12A.
A11 T8A. T16A.
Make sure that the power amplifier is disconnected from the mains.
At the power amplifier rear panel is placed the fuse holder. Unscrew the most external part of
the fuse holder.
Upon unscrewing the most external part of the fuse holder, the fuse will appear. Remove it
and change for a new one. Never use other type of element than a fuse.
Screw the external part of the fuse holder.
CAUTION: Always make sure upon changing the fuse, that this is the adequate.

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
CONNECTING TO THE MAINS
The connection of thepower amplifier to themains takes place by means of a three-wire cord
provided by the factory. The European standard colour code is: Brown-Live, Blue-Neutral and
Yellow/Green-Earth, keeps in mind this mains configuration, whenever handle the power amplifier
plug.In the connection of several devices to the same AC distribution boardand extension cables,
keeps in mind the maximum current of the power amplifier, and make sure that the mains
connector, as well as the AC distribution board, are of enough current capacity, since could take
place in the mains connector, and in the same AC distribution board a overheating, with the risk of
fire and/or short circuit. The following list shows the maximum average current requirement of the
different models of power amplifiers at normal music operation:
MODELS MAXIMUM CURRENT REQUIREMENT
A3.5 2A.
A7 4A.
A11 6A.
Make sure that the power amplifier power switch is at position 0 (turned off).
Insert the male connector of the three-wire cable into the mains plug.
Turn on the power amplifier power switch. Right now the power amplifier will turn on.
CAUTION: Make sure that the mains voltage is the correct, as well as their fuse is the adequate.
INPUT CONNECTION
Each power amplifier's channel incorporates one XLR-3-31 female connector. The inputs are
balanced, with a nominal impedance of 20 KΩ(10 KΩunbalanced). The next list shows the input
pins correspondence as A.E.S recommendation practice:
INPUT CONNECTOR XLR-3-31
PIN 1 GND
PIN 2 HOT (+)
PIN 3 COLD (-)

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
The input connectiondepends on two factors, the first is the type of input signalbalanced or
unbalanced, and the second the ground configuration of the sound source (floating or ground-
referenced). The next pictures shows some of the different possibilities of connection, relying on the
type of input signal, balancedor unbalanced and according to the ground configuration of the
equipment (floating or ground-referenced).
In the next diagrams, we use the following symbols:
Sound source with mainscord without ground connection.
Sound source with mains cord with ground connection.
Sound source with the EARTH-LINK OFF.
Sound source with the EARTH LINK ON.
UNBALANCED INPUT: This type of connection will be used when the sound source doesn't provide
balanced output. If it is possible, will be employed the connection type 1.
1) Using twin-lead shielded cable:
Floating sound source ( or )
Ground-referenced sound source ( or )
2) Using single conductor coax cable:
Floating sound source ( or )

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
Ground-referenced sound source ( or )
BALANCED INPUT:
Floating sound source ( or )
Ground-referenced sound source ( or )
OUTPUT POWER CONNECTION. MODES OF OPERATION
Each channel includes a pair of five-way binding post. The red binding post is positive and the
black is ground. Keep in mind thepolarity upon connecting the speakers since changing the
speaker polarity of a system reduces the total output power by the effect of the phase cancellations
mechanisms.
In the output connection it is necessary to keep in mind a series of important precautions in
order to avoidan accidental short circuit or a possible damage in the equipment:
Consider the power-handling capacity of your speakers before connecting it to the power
amplifier. Equipos Europeos Electrónicos is not liable for damage occurred by the connection of
speakers to the power amplifier with anominal power lower that the power amplifier.
Turn off the power amplifier and turn down the input attenuators, whenever takes place
an output power connection. The output power connectors could have high voltage, with
the rising danger of short circuit.

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
Never put the output power connectorsin parallel. This connection doesn't increase the
power and could cause the break of the power amplifier.
Do not connect the power amplifieroutput connectors to the output connectors of any
other power amplifier. This connection could cause the break of one or both power
amplifiers.
Do not connect the output connector ground (blackbinding post) to any input connector
ground (PIN1 of the connector XLR-3-31). This could create a ground loop and could cause
feedback oscillations.
Use loudspeaker cables sizes capable to manage the output current of the power
amplifier. The selection of a good loudspeaker cable, with a good quality and an adequate
diameter is very important, and is one of the things that less is kept in mind.
The next list shows the maximum output current of the power amplifiers according to the
model:
MODELS MAXIMUM OUTPUT CURRENT
A3.5 9A.
A7 13A.
A11 16,5A.
There are many factors that determine the loudspeaker cable diameter: the length of the
cable, the type of signal that is going to circulate for it, the output power of the power amplifier etc.
A cable with high resistance reduces the damping factor, limiting the power amplifier capacityfor
controlling the speakers accurately.
The possible output connections, depends on the configuration of the STEREO/BRIDGE mode
switch on the rear panel:
CAUTION: Do not change the configuration of STEREO/BRIDGE switch unless the power amplifier is
first turned off. Before turn on the power amplifier, make sure that the mains, input and output
connections are correct. If doesn't follow theserecommendations, could cause a power amplifier
and/or loudspeakers breakdown.
STEREO MODE OPERATION: In this mode the two channels of the power amplifier are totally
independent, so that the two input signals, and the two power outputs will be wiring
independently. In order to configure the power amplifier in STEREO mode, turn the amplifier off,
slide the STEREO/BRIDGE switch toward the left (as you face the rear panel), and wire the input and
output connections according to the next picture:

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
BRIDGE MODE OPERATION: In BRIDGE mode, the input should be inserted on the XLR CH! input
connector. In this mode the power of the two channels will be added over a single load. The CH1
input attenuator controls both channels, remaining the CH2 input attenuator disabled. The output in
BRIDGE mode, must be taken between both red binding post (positive load pole is the red binding
post of CH1 and the negative load, the red binding post of CH2). To put the power amplifier in
BRIDGE mode, turn the power amplifier off, slide the STEREO/BRIDGE switch toward the right (as you
face the rear panel), and wire the input andoutput connections according to the following picture:
EARTH LINK
In some installations, it might be necessary to isolate the power amplifier input signal electric
ground, from the system mains earth, in order to avoid ground loops, that could generate
unwanted noises. For this reason, the power amplifier provides an EARTH-LINK switch placed at the
rear panel to lift themains earth from the power amplifier input signal electric ground.

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
MAINS EARTH LINKED WITH THE P. AMPLIFIER INPUT SIGNAL ELECTRIC GROUND.
MAINS EARTH LIFTED FROM THE P. AMPLIFIER INPUT SIGNAL ELECTRIC GROUND.
CAUTION: Sometimes, lifting the mains earth, by using a ground-lift connector,
cancels some hum noises on the audio system, but this is very dangerous and not
advisable, because should any circumstance part of the mains signal is derived to
the chassis, could cause a short circuit through our body, upon having eliminated
one of the working precautions of the unit. For this circumstance, NEVER lifts the
mains earth (use the EARTH-LINK switch of the unit) in order to avoid possible
accidents.
5. OPERATION
POWER UP
Plug in all input and output connectors (following the recommendations of the
sections INSTALLATION - INPUT CONNECTION AND INSTALLATION - OUTPUT
CONNECTION). Ensure that both power amplifier's input attenuators are turned fully
counter-clockwise ( -∞position). At this time you can switch on the power amplifier.
Upon switch the power amplifier on, the delay turn on system takes place, that minimises the
effect of the transient currents on the loudspeakers. In a few seconds, the delay turn on system
stops working (a RELAY click will be listened) and the load is connected.
When turning on a rack of power amplifiers they should be switched on individually. The
practice of leaving all power amplifiers in a rack switched on and powering up the whole rack by
connecting it to the mains is dangerous and likely it blows the mains fuse of the rack power supply,
if with good approach, the rack has one. In a rack of power amplifiers, switch the power amplifiers
on in a one by one basis.
Note that upon switching the power amplifier on, the ON/PROTECT indicator ON/PROT lights red
(indicating that the power amplifier is cutting the output signal), and after a few seconds this led
changes to green and a RELAY click will be listened indicating that the power amplifier is connecting
the output signal to the loudspeakers. At this time you can turn up the power amplifier input
attenuators.
INPUT ATTENUATORS
Each power amplifier channel has an input signal attenuator, gauged. The
calibration is measured between ±1 dBu relative to the scale.
The input attenuators are independent for each channel in STEREO mode. In mode
BRIDGE both channels depend on the CH1 input attenuator.
CLIP INDICATORS (INPUT SIGNAL OVERLOAD)
The CLIP red LED
CLIP
, illuminates when the power amplifier starts to saturate, moreover, if
the limiter is ON, this LED indicates that the circuit limiter starts to work (for more information see
0
1

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
section SPECIAL OPERATIONS- LIMITER CONFIGURATION). The CLIP indicators
CLIP
are independent
in each channel, and indicate a real saturation,by comparing input and output continuously, and
are independent of the mains voltage.
The CLIP indicators
CLIP
also illuminates when there is an output short-circuit, whenever one
input signal is being introduced to the power amplifier.
To make the loudspeakers life longer, avoid this situation of overload during extended periods
of time.
If the input signal level is too high, don't turn the power amplifier limiter off, because it is an
efficient protection for the loudspeakers.
In general, the loudspeakers resist high peaks of instantaneous power, but when exposed to
extended saturations they lose any guarantee of good operation.
The saturation measuring circuit is sensitive to peaks; it has a quick attack time and a slow
release time.
SIGNAL INDICATORS
The SIGNAL green LEDs
SIGNAL
illuminates when the output signal of the corresponding
channel reaches 25 dBu before saturation.
These LEDs indicate signal presence in the power amplifier input.
This SIGNAL measurement circuit is sensitive to peaks; it has a quick attack time and a slow
release time to indicate the average power.
ON/PROTECT INDICATORS
The ON/PROT LED ON/PROT
indicates the connection or disconnection of the loadfrom the power
amplifier. These bi-colour LED ON/PROT ON/PROT illuminates in red when the load is disconnected
from the power amplifier and it illuminates in green when the load is connected to the power
amplifier.
Therefore, whenever this indicator is in red, will indicate us that the load is disconnected from
the power amplifier, and the power amplifier is not operative at that moment. This occurs when the
power amplifier is turned on, and when the ERROR or THERMAL protections are activated.
When the power amplifier output transistors reach 90ºC, the thermal protection circuit of the
corresponding channel is activated. The thermal protection, disconnects the load from the power
amplifier, turning red the ON/PROT LED ON/PROT of the corresponding channel. This only happens
under themost severe conditions of continuous overload; in such a case, it is essential to localise
and to rectify the cause of this overheating condition. The thermal protection circuit returns
automatically to its normal operation when the power amplifier output transistors drops under the
security level, connecting the load again, and turning green the ON/PROT LED ON/PROT
.
The power amplifier load protection circuit, work when a continuous voltage appears in the
power amplifier output connectors, disconnecting the load from the power amplifier (the ON/PROT
LED ON/PROT of the corresponding channel illuminates on red). When the continuous voltage
disappear, the load protection circuit automatically, connects the load to the power amplifier, and
the ON/PROT LED ON/PROT turns green.
The power amplifier has two ON/PROT LED ON/PROT indicators, one per channel.

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
FAN
The power amplifier includes a thermally controlled system, which continuously regulates the
fan speed depending on, the heat energy it has to evacuate. This variable speed circuit avoids
abrupt changes of temperature and substantially extents the working life of the components builds
in. At power amplifier turn on, the fan rotates at maximum speed, inorder to exhaust the maximum
dust possible. Soon after, the fan's speed drops to normal speed. The power amplifier fan rotates at
maximum speed also, in an overheating situation (when a thermal protection is activated) so that
the heat drops under the security level quickly.
The fan is placed inside the power amplifier, and incorporates some cooling vents in the front
and rear panel for which the air is evacuated, for that reason it is important make sure that the
cooling vents are always free so that the air could circulate with freedom.
LOAD IMPEDANCES
The power amplifiers ADVANTAGE series, are designed to drive a 4Ωor higher load
impedances in STEREO mode (8Ωor higher in Mode BRIDGE), without current limiting.
When the power amplifier is working in BRIDGE mode, the load impedance must be 8Ωor
higher, with the same consideration that in STEREO mode with 4Ωload impedance. This is because
in BRIDGE mode, each channel is like driving with the half load impedance.
MAINTENANCE
Periodically, and in a technical service, you must clean the dust and dirt accumulated inside
the power amplifier, especially in the heatsinks, the fan and the cooling vents, with a vacuum
cleaner or with an air-compressor gun. The dirt diminishes considerably the capacity of radiation
and ventilation.
The input attenuators (potentiometers) are sensitive to the dust accumulated, and therefore for
trouble free operation they must be cleaned with an air compressor gun or be changed if
necessary.
NOTE: Equipos Europeos Electrónicos don't recommend the use of spray cleaners because they
could damage the lubricant layer of the potentiometers. Use compressed air to clean them or
replace with similar parts.
AMPLIFIER CONDITIONS
INDICATORS AMPLIFIER CONDITION
The power amplifier has just been turned on (it is still in
the initial delay) and it is not receiving an input signal. In
this case the ON/PROT indicators of both channels
would be illuminated in red.
OR
A protection was activated (ERROR or THERMAL). The
power amplifier is not receiving an input signal. In this
case would be illuminated inred the ON/PROT indicator
of the channel in which the protection has been
activated.

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
INDICATORS AMPLIFIER CONDITION
The power amplifier has just been turned on (it is still in
the initial delay) and it is receiving an input signal. In this
case the ON/PROT indicators of both channels would be
illuminated in red.
OR
A protection was activated (ERROR or THERMAL). The
power amplifier is receiving an input signal. In this case
would be illuminated in red the ON/PROT indicator of the
channel in which the protection has been activated.
The channel with this indicator status is not receiving an
input signal, but is ready in order to receive it.
Normal operation. The channel with this indicator status is
receiving an input signal, and amplifying it.
The channel with this indicator status is receiving an input
signal too high. If the limiter is engaged, it will be working,
and if it is not engaged, the output signal will be
saturated.
The channel with this indicator status has its output in
short-circuit
There is no power tothe amplifier, either because it is not
plugged or because the power switch is in the OFF
position.
INDICATORS RED: GREEN:
6. SPECIAL OPERATIONS
In order to configure some of the power amplifier possibilities it is necessary to open it,
removing the nine screws on the upper cover.
NOTE: This type of operations takes place with the unit open, for what it should be carried out by a
qualified technician.
DANGER: Before opening the amplifier, disconnect it from the mains. It is important to indicate that
although theunit ispower out (with the power switch in 0 position), if it continues connected to the
mains there are different parts of the unit that are subjected to high voltage.
CAUTION: Protect the power amplifier from the rain and moisture, mainly if it is open. If liquid is
spilled into the power amplifier, disconnect it from the mains and consult a qualified service
technician.
The input sensitivity and limiter configuration of both channels, takes place in the driver card,
shown in the next figure (DRIVER A5/11 ALTAIR -081). This board is located parallel to the power
amplifier bottom plate. The driver board is wide, occupying almost the whole width of the power
amplifier. The input sensitivity configuration of both channels is close the XLR-3-31 of CH1, and the
limiter configuration is close the XLR-3-321 of CH2.

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
The voltage selector is placed in the left side of the power supply card, shown in the next
figure (POWER SUPPLY A5/11 ALTAIR -082). The power supply card is located in the front-left side of the
power amplifier, (as you face the front panel).
S2 0 dBu.
SENS.
CH2
S1
0 dBu.
SENS._CH1
ON
OFF
J4
LIMITER

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
INPUT SENSITIVITY/GAIN ADJUST
The power amplifier input sensitivity may be configured with two resistors, one for each
channel. When not installed this resistors, the input SENSITIVITY (input level necessary in order to
produce the maximum output level) of the channel is 0 dBu, and with a resistor of 3K16 we obtain a
input SENSITIVITY of +8 dBu. These are the two extreme values of the resistor to configure the input
sensitivity. The factory configuration is with input sensitivity 0 dBu.
Channel 1 Channel 2
The different resistors to obtain input sensitivities between 0 dBu and +8 dBu are show in the
next table:
INPUT SENSITIVITY RESISTOR (1/4W, 1%)
0 dBu (0,77 V). Without resistor.
+1 dBu (0,87 V). 42K2.
+2 dBu (0,98 V). 20K0.
+3 dBu (1,10 V). 12K1.
+4 dBu (1,23 V). 9K09.
+5 dBu (1,38 V). 6K81.
+6 dBu (1,55 V). 5K23.
E+7 dBu (1,74 V).N(1/4W, 4K02.
+8 dBu (1,95 V). 3K16.
CAUTION: Never put a resistor to configure the input sensitivity less than 3K16. This can produce a
misoperate of the power amplifier.
The gain (times that the output signal is increased with respect to input signal), depends on the
power amplifier model, as well as of the input sensitivity configuration. In the next table is shown
the gains according to the power amplifier model and its input sensitivity configuration (with
intermediate input sensitivities, subtract the gain corresponding to 0 dBu with the configured input
sensitivity, and obtain the power amplifier gain i.e.: 36-6 = 30).
GAIN (dB)
INPUT SENSITIVITY
MODELS 0 dBu (0,775 V). +8 dBu (1,95 V).
A3.5 31 23
A7 34 26
A11 36 28
LIMITER ON/OFF
The power amplifier's limiter reduces the input signal when the power amplifier starts to
saturate, which avoids high saturation and loudspeaker damage.

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
It is very advisable use the limiter circuit.
When the limiter ON/OFF switch is not pushed, the limiter is enable (ON). When this switch is
pushed, the limiter is disable (OFF).
The limiter configuration (ON/OFF) affects to both channels of the power amplifier.
The factory configuration is with the limiter enable (ON) in both channels.
LIMITER CONFIGURATION
Configuration Switch position
CH1 -> LIMITER ON.
CH2 -> LIMITER ON.
ON
OFF
J4
LIMITER
CH1 -> LIMITER OFF.
CH2 -> LIMITER OFF.
ON OFF
J4
LIMITER
CHANGING THE MAINS VOLTAGE
The power amplifier is set to operate at 230V, 50-60Hz or at 115V, 50-60Hz.
Make sure that the power amplifier is disconnected of the mains.
Set up the voltage selector, placed in the left side of the power supply card (POWER SUPPLY
A5/11ALTAIR -082), in the position that showsthe voltage that you want to connect it.
Power Amplifier set up 115 V.
Power Amplifier set up 230 V.
Make sure that the fuse is the right one for the selected voltage:
MODEL FUSE (230V. 50-60 Hz) FUSE (115V. 50-60 Hz)
A3.5 T5A. T8A.
A7 T6A. T12A.
A11 T8A. T16A.

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PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
7. DISTRIBUTED SYSTEMS APPLICATION (PUBLIC ADDRESS)
Currently, the standard of public address PA, uses loudspeakers of 70.7 Volts and 100 Volts
with different powers. The professional power amplifiers ADVANTAGE series could work with these
public address systems. In order to use the power amplifiers in distributed systems, it is necessary to
choose the loudspeaker voltage operation (and therefore the power amplifiermodel) and wire the
loudspeakers in parallel and then to the power amplifier output, always keeping in mind that the sum
of the loudspeaker power placed in parallel with the power amplifier output should not never
overcome the maximum acceptable power of the amplifier. The next table shows the voltages and
powers to choose from.
Note that both configurations are in Bridge mode so, never refer any loudspeaker to ground in
the sound system installation.
OUTPUT POWER Watts RMS 1KHz, THD+N 0,1%
Bridge mode
MODEL 70,7 V LINE 100 V LINE
A3.5 -- --
A7 700 --
A11 -- 1100
8. OPTIONAL CROSS-OVER CARD.
An optional crossover card is available as anoption to be installed and configured by using a
simple screwdriver.
The card provides High and Low frequency crossover outputs of 24 dB/octave L-R type.
Refer to its corresponding user manual for proper operation.

20
PROFESSIONALPOWER AMPLIFIERS ADVANTAGE SERIES
9. TECHNICAL SPECIFICATIONS
MODEL A3.5 A7 A11
OUTPUT POWER IN WATTS
(RMS, 1KHz, THD < 0,1%) 8Ω100 200 300
Stereo mode:
(per channel, botch channel driven) 4Ω175 350 550
Bridge mode: 8Ω350 700 1100
8Ω120 230 350
Dynamic power EIA RS-490:
(Botch channels driven) 4Ω220 410 650
TOTAL HARMONIC DISTORTION (THD+N): Less than 0,05% at rated output power at 1 kHz into 4 Ω.
INTERMODULATION DISTORTION SMPTE: - Less than 0,08% at 60Hz, 7KHz, 4:1 ratio,
into 4Ω. at rated output power.
DIM-30: - Less than 0,04% into 4Ω.
INPUT SENSITIVITY:
at rated output power (4Ω)Internally selectable by means of resistor:
From 0 dBv (0.775 V) to +8dBv (1.95 V).
INPUT IMPEDANCE: Balanced: 20 KΩ.
Unbalanced: 10KΩ.
COMMON MODE REJECTION RATIO (C.M.R.R.): Greater than 70 dB, 20 Hz to 10 KHz.; 90 dB at 50 Hz.
DAMPING FACTOR: Greater than 300 at 1 KHz into 8Ω.
HUM AND NOISE:
("A" weighted) Greater than 100 dB, 20Hz to 20KHz ref. full output.
FREQUENCY RESPONSE: 20 Hz to 20KHz (-0,5 dB).
OUTPUT SLEW RATE: Typically 20 V/us.
CHANNEL SEPARATION: Greater than 65 dB at 1KHz.
INPUT CONNECTORS PER CHANNEL: XLR-3-31 Balanced.
OUTPUT CONNECTORS PER CHANNEL: Binding post.
INDIDATORS: CLIP LED (one per channel).
SIGNAL LED (one per channel).
ON/PROT LED (one per channel).
COOLING: Forced air by continuous variable speed fan. Front to rear cooling.
PROTECTIONS: Electronic against short-circuit and open circuit.
Thermal against output transistors overheats.
DC out by relay. Delayed turn on/off
Mains inrush transient. (A7, A11 only)
POWER SUPPLY: 115/230 Volts + 10%, -30%, 50/60 Hz.
POWER REQUIREMENTS AT FULL OUTPUT: 350 V.A. 700 V.A. 1100 V.A.
NET/SHIPPING WEIGHT: 11 Kg. / 14 Kg. 14 Kg. / 17 Kg. 15 Kg. / 18 Kg.
DIMENSIONS 483x89x370 m/m (19" x 2 u.).
RACK MOUNTING: 430 m/m deep needed including external XLR's.
NOTE: EQUIPOS EUROPEOS ELECTRÓNICOS S.A.L. reserves the right to modify the technical
specifications without previous notice.