Inter-m R-150 User manual

R-150/R-300/R-500
Reference Series Amplifier
Copyright 2004 Inter-M Corporation

R-150/R-300/R-500 Reference Series Amplifier
Contents
Welcome ..................................................................................................................................... 3
Unpacking ............................................................................................................................... 3
Warnings .................................................................................................................................. 3
Operation................................................................................................................................. 5
Features ....................................................................................................................................... 6
Front Panel Controls.................................................................................................................... 7
Operational Modes .................................................................................................................. 11
Speaker Impedance and Connections .............................................................................. 11
Speaker Connection Procedures............................................................................................ 12
Speaker Cable ...................................................................................................................... 13
Maintaining Proper Polarity .................................................................................................. 13
Rack Mounting Your Amplifier ............................................................................................. 13
Block Diagram .......................................................................................................................... 14
Specifications............................................................................................................................ 15
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R-150/R-300/R-500 Reference Series 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 R-150/R-300/R-500 Reference Series Amplifier 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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R-150/R-300/R-500 Reference Series 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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R-150/R-300/R-500 Reference Series Amplifier
Operation
Make certain that speakers and input sources are properly connected before switching
AC Mains power 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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R-150/R-300/R-500 Reference Series Amplifier
R-150/R-300/R-500
Power Amplifier
Features
High Performance Monitor Amp
• Studio quality monitor amp provides clean sound for the studio, conference room,
concert hall and commercial installations.
Advanced Protection Circuitry
• Thermal and current overload protection, short and open circuit protection, power-
on delay, for component and loudspeaker protection.
Ultra-Efficient Cooling System
• Convection cooling uses no fan, providing ultra-quiet performance in critical
applications.
Bridged Mono and Input Parallel Operation
• Bridged mono and input parallel modes for increased power and versatility.
Versatile Connectivity
• Balanced and unbalanced inputs on XLR and 1/4” phone connectors, as well as
speaker connect and five-way binding post output connectors to accommodate a
wide array of system options.
LED Indicators
• Front panel LED indicators show power, clip, protection and level status.
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R-150/R-300/R-500 Reference Series Amplifier
Front Panel Controls
1. Power Switch
Pushing this switch up swiches the unit on. Pushing it down swiches the unit off.
2. Power Indicator LED
When the unit is switched on, the Power LED will glow steadily.
3. Protection Indicators
There are two protection indicator LEDs – one LED for Channel 1 of the amplifier
and one LED for Channel 2. These LEDs indicate 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.
(Note that the Protection Indicators light for approximately six seconds when the
amplifier is first switched on.)
The amplifier offers the following modes of protection:
Thermal Protection: Activates when internal operating temperature exceeds 100˚
Celsius.
Compressor/Limiting: When maximum output power is reached, output level will
be reduced to avoid distortion.
DC Fault Protection: DC detection circuitry shuts the speaker output when a DC
fault voltage of ±3dB or greater is detected.
Power On/Off Muting: Audio to speakers is delayed for several seconds on
powering on and off to reduce potential speaker damage from transients.
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R-150/R-300/R-500 Reference Series Amplifier
4. Input Attenuators
These are detented controls for regulating each channel’s input level. Clockwise
rotation increases gain.
5. Handles
Use these handles to easily move the amplifier.
6. Clip Indicators
The red CLIP LED indicates an excessive output level, lighting when distortion
reaches approximately 1%. Do not operate the unit with the CLIP LED steadily
illuminated.
7. Output Level Indicators
The LEVEL LED indicates the amplifier’s output status, lighting when audio signal
reaches –15dB.
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R-150/R-300/R-500 Reference Series Amplifier
Rear Panel Controls
1. Speaker Output Terminals
These five-way binding posts and speaker connect jacks are used to connect
speakers to the unit.
Speakers may be connected in Stereo or Bridged Mono mode. Please refer to the
illustrations below. When connecting speakers in Bridged Mono mode, use the
Channel 1 “+“ output for the positive lead, and the Channel 2 “+“ for the
negative lead.
2. AC Connector
Connect the supplied standard AC input cable here.
3. Mono/Stereo Mode Selector
Use this slide switch to select either Stereo or Bridged Mono operation. When
Bridged Mono mode is selected, only Channel 1 is active. Use the Channel 1
Input Attenuator to set input level, and refer to the corresponding indicator LEDs
for operating status.
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R-150/R-300/R-500 Reference Series Amplifier
4. Input Connectors
Balanced input connectors are provided on XLR jacks, while unbalanced
connections can be made using the 1/4” phone jacks. (When operating in
Bridged Mono mode, only Channel 1 input is active.)
5. Heat Sink
Heat is emitted via the external HEAT SINK when the amplifier is switched on.
When the amplifier is rack mounted, we recommend that you keep the rear of
the rack open in order to release heat.
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