McIntosh MC 2250, Руководство пользователя

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The Front Panel Controls and
How to Use Them
GAIN CONTROLS
When your system is first connected, turn the
LEFT and RIGHT/Mono GAIN controls to minimum
(fully counterclockwise) before turning the power on.
The controls can then be advanced to the desired
settings; normally maximum (fully clockwise). When
using the MC 2250 for MONO-BRIDGE or MONO-
PARALLEL operation, use the RIGHT/Mono GAIN
control. The LEFT channel control is not used in the
MONO mode of operation.
HEADPHONES
The stereo HEADPHONE jack is located next to
the power switch. The headphones are driven by left
and right preamp sections in the MC 2250. The
preamp circuits have been designed to power low
impedance dynamic headphones. High impedance
headphones will work but at a reduced listening
level. The HEADPHONE output is not affected by the
SPEAKER switch.
SPEAKERS
The SPEAKER switch turns the loudspeakers on
or off. The switch must be in the ON position to hear
sound from the loudspeakers. When the switch is
OFF, you can listen to headphones in private.
POWER
The POWER switch turns the MC 2250 ON or OFF.
Each time the power is turned on, the red SYSTEM
TEST readout and green POWER GUARD lights will
be alternately visible as the self test sequence auto-
matically proceeds. The switch does not control the
power outlet on the back panel. If you wish to con-
trol the AC power from a preamplifier control center,
plug the AC cord of the MC 2250 into a controlled
outlet on the rear of the preamplifier control center
and leave the POWER switch in the ON position.
POWER GUARD
Each channel of the MC 2250 is equipped with a
POWER GUARD circuit. POWER GUARD prevents
the MC 2250 from causing high distortion when the
input is overdriven. It acts automatically when dis-
tortion exceeds 0.5%. As long as the amplifier is not
overdriven, the NORMAL green POWER GUARD
lights will stay on. If the input signal is excessive for
either or both channels, the corresponding red LIMIT
light will go on instead. The sound will remain clear
and undistorted. When the excessive driving signal
is removed, the NORMAL green lights will return.
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