Inter-m PA-9336 User manual

PA-9312/PA-9324/PA-9336
Power Amplifier
Copyright 2004 Inter-M Corporation

PA-9312/PA-9324/PA-9336 Power Amplifier
Contents
Welcome ..................................................................................................................................... 3
Unpacking ............................................................................................................................... 3
Warnings .................................................................................................................................. 3
Operation................................................................................................................................. 5
Features ....................................................................................................................................... 6
Front Panel Controls.................................................................................................................... 7
Connections.............................................................................................................................. 10
Connecting Speakers............................................................................................................... 11
Specifications............................................................................................................................ 12
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PA-9312/PA-9324/PA-9336 Power Amplifier
Welcome
A personal welcome to you from the management and employees of Inter-M
Thank you for purchasing this fine Inter-M product. All of us here at Inter-M are dedicated
to providing you with the highest quality products and the best value.
We sincerely trust this product will provide you with years of satisfactory service, but if
anything is not to your complete satisfaction, we will endeavor to make things right.
Welcome to Inter-M, and thank you for becoming a part of our worldwide extended
family!
Unpacking
Although your PA-9312/PA-9324/PA-9336 is neither complicated nor difficult to operate,
we recommend you take a few minutes to read this brief manual and familiarize yourself
with the important information regarding product features, setup and operation.
As with most electronic devices, we strongly recommend you retain the original
packaging. In the unlikely event the product must be returned for servicing, the original
packaging (or reasonable equivalent) is required.
Warnings
Environment
Never place this product in an environment that could alter its performance or reduce its
service life. Such environments are usually characterized by high levels of heat, dust,
moisture, or vibration.
Safety
1. Read these instructions carefully.
2. Follow all instructions.
3. Keep all warnings.
4. Do not operate this apparatus near water.
5. Clean only with a damp cloth.
6. Do not block any of the ventilation openings.
7. Install only in accordance with the instructions in this manual.
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PA-9312/PA-9324/PA-9336 Power Amplifier
8. Do not install near any heat sources such as radiators, heat registers, stoves, or other
devices (including amplifiers) that produce heat.
9. Do not defeat the safety purpose of the polarized or grounding type plug. A polarized
plug has two blades, with one wider than the other. A grounding type plug has two
blades and a third grounding prong. The wide blade or the third prong is provided for
your safety. If the provided plug does not fit into your outlet, consult an electrician for
replacement of the obsolete outlet.
10. Protect the power cord from being walked on or pinched, particularly at plugs,
convenience receptacles, and the point where it is attached to the apparatus.
11. Use only the attachments/accessories specified.
12. Use only with a cart, stand, tripod, bracket, or table specified, or sold with the
apparatus. When a cart is used, use caution when moving the cart/apparatus
combination to avoid overturning.
13. Unplug this apparatus during lightning storms or when unused for long periods of
time.
14. Refer all servicing to qualified service personnel. Servicing is required when the
apparatus has been damaged in any way, such as power supply cord or plug is
damaged, liquid has been spilled or objects have fallen into the apparatus, the
apparatus has been exposed to rain or moisture, does not operate normally, or
has been dropped.
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PA-9312/PA-9324/PA-9336 Power Amplifier
Operation
Make certain that speakers and input sources are properly connected before switching
on.
Keep volume levels at minimum gain before switching on.
NOTE: The system’s operation is delayed by approximately three seconds after pressing
the AC Mains power switch. This is due to the built-in protection circuitry, designed to
protect speakers and other system components.
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PA-9312/PA-9324/PA-9336 Power Amplifier
PA-9312/PA-9324/PA-9336
Public Address Power Amplifier
Features
High Power, Low Distortion
• 120W (PA-9312), 240W (PA-9324) or 360W (PA-9336) of RMS power, with less than 1%
THD.
Balanced Input
• Balanced XLR inputs to reduce ground hum and increase efficiency.
Gain Adjustment
• Input gain is adjustable from –12dB to 0dB (1V) via rear panel control.
Emergency Battery Backup
• Emergency battery backup for unexpected AC power failure.
Slim Design, Compact Size
• Streamlined design fits in a compact 3RU space.
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PA-9312/PA-9324/PA-9336 Power Amplifier
Front Panel Controls
1. Power LED
When the unit is powered on, the Power LED will glow steadily.
2. Power Switch
Pressing this switch switches the unit on, as indicated by the Power LED (1).
Pressing it again switches the unit off.
3. Output Level Indicators
These three LEDs indicate the amplifier’s output status. The –40dB LED indicates
the presence of audio signal at the amplifier’s output. The –10dB LED indicates
output at nominal operating range. The red CLIP LED indicates an excessive
output level. Do not operate the unit with the CLIP LED constantly on
(illuminated).
4. Protection Indicator
This LED indicates the state of the amplifier’s protection circuitry. When the
Protection LED is on (illuminated), the protection circuitry is active, indicating that
the unit is not operating normally. This is typically due to overheating or power
limiting. Please check the Input and Output condition of the amplifier.
5. Fan Vents
These vents provide cool air flow into the unit. It is important to keep them free of
obstructions, to prevent the unit from overheating. It is also important to operate
the unit in a dust-free environment.
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PA-9312/PA-9324/PA-9336 Power Amplifier
Rear Panel Controls
1. Speaker Output Terminals
These terminals are used to connect speakers to the unit. You may select either
4or 8conventional operation, or High Impedance operation at either 70V or
100V. Make certain the combined impedance of the speakers is equal to or
higher than the rated output impedance of the amplifier.
MODEL 4Ω70V 100V
PA-9312 22V 4283
PA-9324 32V 2142
PA-9336 38V 13.627.8
2. Audio Inputs
These balanced XLR jacks are for the input of audio signal.
3. Level Control
This knob controls the amplifier’s output level, from –12dB to 0dB (reference input
of 0dB at 1V). Rotating the knob clockwise increases the level, and rotating it
counter-clockwise decreases the level.
4. Fuse Holder
This holder contains the AC overload protection fuse. If the fuse has blown out,
replace it with a fuse of the same type and rating.
If the fuse continues to blow, refer servicing to a qualified service technician.
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PA-9312/PA-9324/PA-9336 Power Amplifier
5. AC Connector
Connect the supplied standard AC input cable here.
6. High-Pass Filter Switch
This switch activates the high-pass filter circuitry, which decreases frequencies
lower than 400Hz by –3dB. The high-pass filter is designed to protect speakers from
damage caused by excessive low frequency transients.
7. Ground Lift Switch
This switch provides for connection or disconnection of the amplifier’s ground to
AC “earth” ground, to prevent noise from ground loops. Under most
circumstances, this switch should be set to FRAME position.
8. DC Input Terminals
These terminals are provided for the connection of backup battery. Connect a
24VDC battery source to these terminals. Make certain the red terminal is
connected to the battery’s positive (+) side, and the black terminal to the
battery’s negative (-) side.
9. Fan Vents
These vents provide hot air flow out of the unit. It is important to keep them free of
obstructions, to prevent the unit from overheating. It is also important to operate
the unit in a dust-free environment.
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PA-9312/PA-9324/PA-9336 Power Amplifier
Connections
10