Bogen M-CLASS AMPLIFIER M450 - Manual (Page 4)

Introduction
Bogen's M-Class amplifiers deliver on what professional sound installers need most: Flexibility, Power, and
Reliability.
Flexibility
The M-Class allows for the installation of up to 2 input modules, accepting inputs from microphones, telephone
systems, stereo sources, mono sources, or daisy-chaining of amplifiers. Each M-Class model comes standard with
a single, professional-quality, stereo, high-impedance balanced input module (BAL1S).
The M-Class has three operating modes to meet different installation needs - Stereo, Dual Mono, or 70V Mono.
Front panel controls allow independent operation of each power amplifier channel in stereo mode. In either
70V Mono or Dual Mono modes, the inputs form a 2:1 mixer with the front panel controls setting the signal
levels from each input. Prioritized input modules and 2:1 mixer operation allow the M-Class to supply the front-
end signal processing required in paging systems and the power to cover any size installation.
Power
With three different models (M600, M450, and M300), the M-Class provides 2-channel operation at 600W,
450W, and 300W per channel into 4-ohm loads. Single channel, 70V Mono operation capacities are 1200W,
900W, and 600W. Along with being powerful, these amplifiers are also compact - using up only 2 rack spaces
(3-1/2") in a standard 19" rack.
Reliability
Driven by a conservatively-rated toroidal power transformer, these amplifiers are built for solid performance
with low distortion and a high slew rate. Output module circuitry is located away from input module circuitry,
minimizing noise and ground loops.The amplifiers require little maintenance and cleaning as internal electron-
ic components are located outside of the forced air-stream flow. Front-mounted fan filters provide easy removal
and cleaning.
M-Class amplifers have a variety of electronic protection circuits including overcurrent, DC voltage, and ther-
mal circuits. A special Clip/Limiting circuit continuously monitors the amount of distortion in the output signal
and reduces input levels as the amplifier approaches clipping. Back-Slope™, Bogen’s unique voltage stabilization
circuitry, regulates the AC energy supplied to the power toroid. This improves both system performance and
reliability despite varying AC supply conditions.
An energy-conserving sleep mode (defeatable) with instant-on return signal operation reduces wasted heat
production in paging systems with intermittent use. In addition, large output heatsinks and dual independently-
controlled, high-output, variable speed fans provide superior cooling and quiet operation while reducing dust
accumulation.
Bogen's M-Class amplifiers are enclosed in a heavy-gauge steel chassis, which prevents mechanical damage to
the unit's internal components even if the unit is subjected to rough handling and excessive portable installa-
tions.The control knobs are located in a recessed section of the cast aluminum front panel to reduce the like-
lihood of mishandling and damage.The angled design of the amplifier's front panel allows easy finger access to
the front knob cover when the amplifiers are stacked tightly in a rack.
Package Contents
* M-Class Amplifier * 2 Rack Ears
* 2 Filters and Grilles * Instruction Manual
* Control Knob Cover * BAL1S Input Module (pre-installed)
* 4 Rubber Feet & Screws
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