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 +
+-