Me ME580, Руководство пользователя

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UNDERSTANDING YOUR ME580
ME Amplifiers Melbourne, Australia
GENERAL DESCRIPTION
The ME580 Power Amplifier is a nominal 100 watt per channel Stereo Amplifier, which may also be
connected as a bridged Mono Amplifier for greater power output. Operation of the ME580 is controlled and
monitored by a microcontroller. Unbalanced AC and DC Direct inputs are provided, as well as Balanced inputs.
Selection of the Balanced or Unbalanced inputs is via a switch located on the rear panel.
In keeping with established ME design philosophy; overall negative feedback is not used, with the
feedback being taken instead from the output of the voltage amplifier stage.
A DC servo is incorporated within the circuitry to ensure that there is no DC offset at the output if
there is a small DC offset at the input when DC input coupling is used.
In addition a Load Compensation switch is provided on the rear panel which allows the user to select
circuitry that ensures minimum distortion irrespective of the speaker load impedance.
The ME580 is equipped with two independently controlled variable speed cooling fans, one for each
channel. The fans are mounted directly on the output transistor heat sinks to provide optimum cooling by
forcing air directly through the cooling fins. This arrangement also provides a degree of acoustic filtering which
reduces fan noise to very low levels. The fans are fitted with ceramic bearings, which help to reduce noise, and
provide a very long service life.
The ME580 also has independent power supplies for each channel, which allows for greater capacity
within the available space, as well as reducing the chance of transient peaks on one channel affecting the
other channel. The power supply has a large capacitor bank fitted, which provides generous peak capacity to
deal with short loud music passages, as well as providing excellent imaging and bass response. A high
capacitance option can be specified, which increases the peak power handling capacity even further.
MICROCONTROLLER MONITORING AND CONTROL
The microcontroller in the ME580 performs a range of monitoring and control functions to optimize the
operation of the amplifier, as well as providing several convenience features, which are described below:
1. Power Up / Power Down Control
Power Up and Power Down are controlled by the microcontroller to reduce surges and possible
speaker “thump” when switching the amplifier on or off.
2. Temperature Monitoring
Continuous independent monitoring of the operating temperature of each output channel and a
further internal temperature sensor is provided. The microcontroller controls the independent
variable speed cooling fans for each channel, to ensure optimum cooling under all operating
conditions. In the event of an over-temperature condition being detected from any of the three
temperature sensors, the microcontroller will shut down the amplifier and run the fans at maximum
speed to clear the over-temperature condition. The status of the temperature monitoring feature is
indicated by the TEMP light on the front panel escutcheon, as follows:
OFF - Amplifier below normal Operating Temperature.
GREEN - Amplifier within normal Operating Temperature range.
AMBER - Amplifier within 5°C of Over-Temperature Shutdown.
RED - Amplifier Over-Temperature Shutdown.
Note: The fans will continue to run after the amplifier is turned off until the ME580 is below 38°C.