Altair MA SERIES User manual

MA Series
MULTICHANNEL PROFESSIONAL
POWER AMPLIFIER
OWNERS MANUAL
V 1.1 web
AUDIO ELECTRONICS DESIGN
AUDIO ELECTRONICS DESIGNAUDIO ELECTRONICS DESIGN
AUDIO ELECTRONICS DESIGN
EQUIPOS EUROPEOS ELECTRÓNICOS, S.A.L
Avda. de la Industria, 50. 28760 TRES CANTOS-MADRID (SPAIN).
34-91-761 65 80 34-91-804 43 58 [email protected]
www.altairaudio.com

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1. Contents:
1. Contents:..............................................................................................................................................................................2
2. INTRODUCTION...............................................................................................................................................................3
Multiple protection ..................................................................................................................................................................3
Clipping circuit limiter ............................................................................................................................................................3
Under control loads .................................................................................................................................................................4
Remote control ........................................................................................................................................................................4
Flexibility ................................................................................................................................................................................4
3. SWITCHES, INDICATORS, ATTENUATORS AND CONNECTORS ...........................................................................4
FRONT PANEL: .....................................................................................................................................................................5
REAR PANEL: .......................................................................................................................................................................6
4. WORKING PRECAUTIONS .............................................................................................................................................7
5. INSTALLATION ................................................................................................................................................................7
UNPACKING..........................................................................................................................................................................7
MOUNTING ...........................................................................................................................................................................7
CHANGING THE FUSE ........................................................................................................................................................8
CONECTING TO THE MAINS .............................................................................................................................................8
INPUT CONNECTION ..........................................................................................................................................................9
UNBALANCED INPUT:..................................................................................................................................................10
BALANCED INPUT:........................................................................................................................................................11
OUTPUT POWER CONNECTION. OPERATING MODES ..............................................................................................11
INDEPENDENT MODE OPERATING (NO BRIDGE) ..................................................................................................13
OPERATING IN BRIDGE MODE:..................................................................................................................................13
MONO CH1+CH2 (CH5+CH6)........................................................................................................................................13
INDEPENDENTS OUTPUTS 3 AND 4 (OUTPUTS 7 AND 8):.....................................................................................13
OUTPUTS 3 AND 4 (7 AND 8) LIKE 1 AND 2 (LIKE 5 AND 6): ................................................................................13
OUTPUTS 3 AND 4 (7 AND 8) LIKE 1+2 (LIKE 5+6): .................................................................................................14
HIGH PASS FILTER (HPF) .................................................................................................................................................14
EARTH LIFT ........................................................................................................................................................................15
6. OPERATION ....................................................................................................................................................................15
POWER UP...........................................................................................................................................................................15
INPUTS ATENUATORS......................................................................................................................................................16
CLIP INDICATORS (INPUT SIGNAL OVERLOAD)........................................................................................................16
SIGNAL INDICATORS .......................................................................................................................................................16
ON/PROTECT INDICATORS .............................................................................................................................................16
FAN .......................................................................................................................................................................................17
LOAD IMPEDANCES..........................................................................................................................................................17
MAINTENANCE..................................................................................................................................................................17
7. REMOTE CONTROL.......................................................................................................................................................18
RVC-1 REMOTE VOLUME CONTROL (Not included in the amplifier)...........................................................................18
Installing............................................................................................................................................................................18
8. INSTALLATION EXAMPLES ........................................................................................................................................18
1. GLOBAL VOLUME CONTROL INSTALLATION ...................................................................................................18
Diagram .............................................................................................................................................................................18
REMOTE CONTROL SETUP..........................................................................................................................................19
MA 150x8 set-up...............................................................................................................................................................19
CONNECTIONS...............................................................................................................................................................19
9. SPECIAL OPERATIONS .................................................................................................................................................20
SENSITIVITY/GAIN ADJUST............................................................................................................................................20
ON/OFF LIMITER................................................................................................................................................................21
REMOTE...............................................................................................................................................................................21
FILTER CHANGE, FRECUENCY, HPF, LPF ....................................................................................................................21
CHANGING THE MAINS VOLTAGE................................................................................................................................21
10. TECHNICAL SPECIFICATIONS ................................................................................................................................22
11. WARRANTY ................................................................................................................................................................23

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NOTICE: PIN 2+
About electronic manual.
The present manual have hypertext, when you click above a cursive text
that mention other part of document ( for example: This ) it will go to this part
of document.
2. INTRODUCTION
Congratulations on your purchase of the ALTAIR MULTICHANNEL series power amplifier. 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 are a lot the characteristics that make of the ALTAIR power amplifiers MULTICHANNEL
series; one of the most highlighted of the audio professional market, here enumerated some:
Multiple protection
The DC output protection and transient suppression commands a relay (per output channel
pairs). It is improved several characteristics of the signal quality by incorporating cascode preamps,
damping factor control and special care to 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 thermal shutdown 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 MULTICHANNEL 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

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or other noticeable cut, it stabilises the output signal integrity, Thereby avoiding overloading and
saturation levels that might damage the system. This limiter effect is switchable on or off internally.
Limiter is not level adjustable. Limiter action depends only upon the excess distortion found in
the output channels.
Under control loads
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, i.e., with zero output
impedance. The MULTICHANNEL series approaches to this nearly zero value presenting a damping
factor better than 300 what redounds to a perfect control of the loudspeaker voice coil position along
their excursion.
Remote control
The MULTICHANNEL Amplifiers series allows a versatile remote control of its channels,
allowing, controlling the 8 channels independently, or in groups. We can install and control a sound
system in different places.
Flexibility
We can use it in multiple configurations since it has 8 channels modular structure, for
example, multichannel amplification of up to 4 stereo ways, independent biamplification, thanks to its
internal filter, like for instance operating with satellites and subwoofer, multi-channel amplification, L R
C, 5,1 etc, amplification in different places, matching channels to duplicate the given power to a
loudspeaker (bridge), mixing two inputs and to amplify the mono signal in several channels.
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 PACKAGING.
3. SWITCHES, INDICATORS, ATTENUATORS AND CONNECTORS
These are the switches, indicators, attenuators and connectors that we could find in your
power amplifier. You will find the description and explanation of each one, it in the corresponding
section.

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FRONT PANEL:
COOLING VENTS
INPUT ATTENUATOR.
INPUT SIGNAL OVERLOAD INDICATOR/LIMITER ACTION
SIGNAL PRESENCE INDICATOR
BRIDGE MODE INDICATOR
ON/PROTECTION INDICATOR
POWER SWITCH
.

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REAR PANEL:
COOLINGVENTS
BINDING POST
FUSE HOLDER. MAINS CORD.
REMOTE VOLUME CONTROL
MONO/ESTEREO SWITCH
ASSIGN INPUTS SWITCH 1,2 OR 3,4, ( 5,6, OR, 7,8)
BRIDGE MODE SWITCH
EARTH LIFT SWITCH
HIGH PASS FILTER SWITCH
INPUT SIGNAL CONNECTOR XLR-3-31
INPUT SIGNAL JACK

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4. 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 the mains.
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 a qualified service technician.
Don't place the power amplifier close to sources of heat. Also make sure that the front, lateral 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 sure of turning off
the power amplifier before handling on these output connectors.
5. 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 sales person
immediately, because the unit must be inspected by a qualified service technician
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 MULTICHANNEL 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 other units 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, lateral and rear
panel should be free, so that the air circulates freely, and the amplifier could have a better heat

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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 this vent.
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)
MA80.4 T5A. T10A.
MA80.8 T6.3A. T12A.
MA150.4 T6.3A. T12A.
MA150.8 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.
CONECTING TO THE MAINS
The connection of the power amplifier to the mains 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 board and 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

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short circuit. The following list shows the maximum average current requirement of the different
models of power amplifiers at normal music operation:
MODEL MÁXIMUM CURRENT REQUIREMENT
MA80.4 2A.
MA80.8 4A.
MA150.4 6A.
MA150.8 8A.
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
The input signal to the power amplifier is made by 8 (4 ) IN Xlr-3-31 female connectors and 8
(4) Jacks 1/4 connectors, both in parallel (XLR with Jack), one XLR and Jack for each channel input.
The inputs are balanced, with a nominal impedance of 20 KΩ(10 KΩ unbalanced), the positive
corresponds to pin 2, and the negative to pin 3 and pin 1 is ground. The following table shows the
correspondence of inputs pins:
INPUT CONECTOR XLR-3-31
PIN 1 GND
PIN2 HOT (+)
PIN3 COLD (-)
PRECAUTION: If you are a user of another old ALTAIR amplifier series having your equipment with PIN
3+, you must change your wiring configuration externally to avoid phase problems.
The input connection depends on two factors, the first is the type of input signal balanced or
unbalanced, and the second the ground configuration of the sound source (floating or ground-
referenced). The next pictures show some of the different possibilities of connection, relying on the

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type of input signal, balanced or 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 mains cord without ground connection.
Sound source with mains cord with ground connection.
Sound source with the EARTH-LIFT ON.
Sound source with the EARTH-LIFT OFF.
UNBALANCED INPUT:
This type of connection will be used when the sound source doesn't provide balanced output.
If it is possible, we recommend the use of 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 )
POWER
AMPLIFIER
SOUND
SOURCE +
+-

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Ground-referenced sound source ( or )
BALANCED INPUT:
Floating sound source ( or )
Ground-referenced sound source ( or )
OUTPUT POWER CONNECTION. OPERATING MODES
Each channel includes a pair of five-way binding post. The red binding post is positive and the
black is negative phase. Keep in mind the polarity upon connecting the speakers since changing the
speaker polarity of a system reduces the total output power by the effect of phase cancellations
mechanisms.
We must connect both wires to the red binding in bridge mode. Follow printing instructions
Hot (+) speaker wire must be connected to red binding 1
and (-) speaker wire must be connected to red binding
post 2 (BRIDGE MODE).
POWER
AMPLIFIER
SOUND
SOURCE +
+-

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There are important precautions to avoid accidental short circuit or possible damage in the
equipment, in output connections.
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 a nominal 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.
Never put the output power connectors in parallel. This connection doesn't increase the
power and could cause the break of the power amplifier.
Do not connect the power amplifier output 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 (black binding post) to any input
connector ground (PIN 1 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:
MODEL MAXIMUN RMS CURRENT
REQUIEREMENT
per channel (4 ohm loads)
MA80.4 4,5A.
MA80.8 4,5A.
MA150.4 6A.
MA150.8 6A
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 capacity for
controlling the speakers accurately. Typical values are 1 to 2,5 mm2.
The possible output connections, depends on the configuration of the MONO, STEREO, BRIDGE
mode switches on the rear panel:
CAUTION: Do not change the configuration of ON/OFF BRIDGE switch unless the power
amplifier is first turned off. Before turn on the power amplifier, make sure that the mains, input and

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output connections are correct. If doesn't follow these recommendations, could cause a power
amplifier and/or loudspeakers breakdown
INDEPENDENT MODE OPERATING (NO BRIDGE)
Both channels are independent in this mode, for that reason we connect both inputs (1-2, 3-4,
5-6, 7-8) and outputs independently.
Be sure that BRIDGE SWITCH is towards right position (rear view).
In order to perform the power amplifier in stereo mode, switch off and then perform it.
OPERATING IN BRIDGE MODE:
In order to perform bridge mode, switch off your power amplifier, then puts switch towards
left (rear view) and wire inputs and outputs connections accordingly.
We use pairs of channels in bridge mode, (CH1-CH2, CH3-CH4, CH5-CH6, CH7-CH8), inputs
should connected thought odd inputs (or putting the switch corresponding to the channels that we
want to put in bridge in MONO) of pairs that we want put in Bridge mode. The power from the two
channels is added to one only speaker.
The input odd attenuator (for example CH1) controls both channels, the even attenuator is
disabled (in this example, CH2)
The output in bridge mode must be, hot (+) speaker connect to red binding odd (in picture 1)
and (-) speaker wire must be connected to red binding post even (2 in image).
MONO CH1+CH2 (CH5+CH6)
The connections may be the same than in independent operating mode, but you must change
mono/stereo switch to mono:
The level is controlled from CH1 (CH5), the input signal comes from mixing CH1 and CH2 (CH5
and CH6). Therefore, we have mono mix CH1 and CH2 (CH5 and 6) signal in (loudspeakers) OUTPUTS
1 and 2 (5 and 6).
INDEPENDENTS OUTPUTS 3 AND 4 (OUTPUTS 7 AND 8):
We have connect loudspeakers in OUTPUTS 3 and 4 (7 and 8), the signal that we want amplify
is connected to inputs CH3 and CH4 (CH7 and CH8).
OUTPUTS 3 AND 4 (7 AND 8) LIKE 1 AND 2 (LIKE 5 AND 6):
We have connect loudspeakers in OUTPUTS 3 and 4 (7 and 8), the signal that we want amplify
connected to CH1 and CH2 (CH5 and CH6). The level is controlled from CH3 and CH4 (CH7 and CH8)

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OUTPUTS 3 AND 4 (7 AND 8) LIKE 1+2 (LIKE 5+6):
We have connect loudspeakers in OUTPUTS 3 and 4 (7 and 8), the signal that we want amplify
connected to CH1 and CH2 (CH5 and CH6).
The level is controlled from CH3 and CH4 (CH7 and CH8)
The connection diagram is similar to the previous one but we must put the switch towards left
HIGH PASS FILTER (HPF)
An active filter 12 dB/oct Butt. type is built in, tuned at 100Hz high pass filter as factory default.
By demand, filter structure, normally configured as HPF can be turned to LPF characteristic. The
cut-off frequency can also be changed to a different one.
If you want more information go to SPECIAL OPERATIONS - FILTER CHANGE, FRECUENCY, HPF,
LPF . Main application is to drive systems with satellites (in HPF mode) and subwoofer in full range.
DISABLED 100 HZ HIGH PASS FILTER

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ENABLED 100 HZ HIGH PASS FILTER
EARTH LIFT
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-LIFT switch placed at the rear panel to
lift the mains earth from the power amplifier pair 1-2 (3-4, 5-6 and 7-8) input signal electric ground.
MAINS EARTH LINK TO THE POWER AMPLIFIER PAIR 1-2 (3-4, 5-6 AND 7-8)
MAINS EARTH LIFT FROM THE POWER AMPLIFIER PAIR 1-2 (3-4, 5-6 AND 7-8)
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.
.
6. OPERATION
POWER UP
Plug in all inputs and outputs connectors (following the recommendations of the
sections INSTALLATION - OUTPUT POWER CONNECTION. MODES OF OPERATION . Ensure
that both power amplifier input attenuators are turned fully counter-clockwise (-∞position).
At this time, we 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

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connecting it to the mains is dangerous and likely, it blows the mains fuse of the rack power supply
when available. 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
blinks (indicating that the power amplifier is cutting the output signal), and after a few
seconds this green doesn’t blink, it light up and a RELAY click will be listened indicating that the power
amplifier is connecting the output signal to the loudspeakers. At this time, we can turn up the power
amplifier input attenuators.
INPUTS ATENUATORS
Each power amplifier channel has an input signal attenuator.
The input attenuators are independent for each channel. In BRIDGE mode, both
channels depend on the odd (CH1, CH3, CH5, CH7) input attenuator.
CLIP INDICATORS (INPUT SIGNAL OVERLOAD)
The CLIP red LED, light on 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
section SPECIAL OPERATIONS - LIMITER ON/OFF
The CLIP indicators are independent for each channel, indicate a real saturation.
The CLIP indicators also light on when there is an output short-circuit, whenever one input
signal is being introduced to the power amplifier.
We must avoid this situation of overload during extended periods, to make the loudspeakers
life longer.
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
extend overload situations they lose any guarantee of good operation.
SIGNAL INDICATORS
The SIGNAL green LEDs illuminates when the output signal of the corresponding
channel reaches approximately -35 dBu before saturation.
These LEDs indicate signal presence in the power amplifier output.
ON/PROTECT INDICATORS
The ON/PROT green LED shows three working states:
Amplifier off, protection mode, amplifier working

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The ON/PROT LED indicates the connection or disconnection of the load from the power
amplifier.
The thermal protection disconnects the load from the power amplifier. This only happens
under the most 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.
Each channel of the power amplifier has an independent load protection circuit.
The power amplifier has ON/PROT LED indicators and relay, one per channel pair (stereo).
FAN
The power amplifier includes a thermally controlled system, which continuously regulates the
fan speed depending on the heat energy it has to discharge. 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, in order 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
lateral 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. The amplifier uses one only
fan, so speed is related to any of the 4 (8) channels needs.
LOAD IMPEDANCES
The power amplifiers MULTICHANNEL series, are designed to drive a 4Ωor higher load
impedances in INDEPENDENT mode (8Ωor higher in BRIDGE Mode), 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 INDEPENDENT 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 heat sinks, 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.

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7. REMOTE CONTROL
The MULTICHANNEL SERIES has remote volume control possibility of each channel. Ask your dealer for
the RVC-1 accessory
RVC-1 REMOTE VOLUME CONTROL (Not included in the amplifier)
Installing
The power multichannel remote control is made thought of RVC-1 unit, you be
able to set-up the channels that you want control inside it.
It may be installed or into standard wall boxes or on surface adaptors.
If would like you can put all switches to ON therefore whit a single RVC-1 you can control all
channels volume * (* it depends on which connector of remote control of the Multichannel power
amplifier you have plug)
• The remote is wiring with a to
standard Cat-5 cable, normally is
used in computer networks it have 8
ways with RJ45 connectors. Pin 1 to
pin 1, pin 2 to pin2, … pin 8 to pin 8.
You should install in cascade (also in parallel, with a cat 5 splitter) to IN/SPLIT input and
SPLIT/IN output
You have two remote volume control connection in each Multichannel Power Amplifier
8. INSTALLATION EXAMPLES
We show the examples with power amplifier MA150.8, or a MA80.8
1. GLOBAL VOLUME CONTROL INSTALLATION
Diagram

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REMOTE CONTROL SETUP
You must put all switches towards on
Connected to REMOTE VOLUME CONTROL CH1-4
1
VOLUME CH1 2 VOLUME CH2 3 VOLUME CH3 4 VOLUME CH4 5 VOLUME CH5-6 6 VOLUME CH7-8
S1 (RVC-1) ON ON ON ON ON ON
MA 150x8 set-up
MODE BRIDGE EARTH LIFT FILTER
CH1-CH2 STEREO OFF * OFF
CH3-CH4 MONO CH1+CH2 OFF * OFF
CH5-CH6 STEREO OFF * HPF
CH7-CH8 MONO CH1+CH2 ON * LPF**
* See section INSTALLATION - INPUT CONNECTION
** See section SPECIAL OPERATIONS - FILTER CHANGE, FRECUENCY, HPF, LPF - Low Pass
Filter (LPF)
CONNECTIONS

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9. SPECIAL OPERATIONS
In order to configure some of the power amplifier possibilities it is necessary to open
upper cover, we need unscrewing the 12 screws.
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 the unit is power 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.
SENSITIVITY/GAIN ADJUST
Input sensibility change is made into unit.
Power amplifier input sensibility (input level necessary to obtain top level output) perform by
means of a resistor (see next table), one for each channel