McIntosh MC205, Руководство пользователя

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Therefore, it is important that they plug directly into
the wall outlet.
Also, most owners desire one power switch for the
whole audio system. The MC205 is equipped with
a circuit that provides remote Power Control from a
McIntosh A/V Control Center. When the A/V Con-
trol Center is switched On, a (+5V) signal operates
the power relay in the MC205. The MC205 also has a
remote Power Control input for Zone B operation (two
of the five channels).
is perfectly preserved.
The MC205 Power
Amplifier with Power
Guard is not limited
to just the rated power
output, but will actually
produce distortion free
output well above its
rated power due to the
McIntosh philosophy of
conservative design.
Power Supply Circuits
To compliment the design of the MC205, there is a
high current power supply for the five power ampli-
fier channels. Refer to figure 20. The very large Power
Transfomer, has toroidal windings on a toroidal core
and can supply over 35 amps of continuous current.
Refer to figure 21 (golf ball is for size comparsion). It
is enclosed in the legendary McIntosh Potted Enclo-
sures and weighs over 12.06kg. The super size main
filter capacitors can store over 310 Joules of energy for
the five amplifier channels, necessary for the wide dy-
namic range that “Digital Audio” demands. The power
amplifier draws high current from the AC power line.
overdriven amplifier can
produce both audible
and inaudible distortion
levels exceeding 40%.
The audible distor-
tion is unpleasant to
hear, but the inaudible
ultrasonic distortion is
also undesirable, since
it can damage valuable
Loudspeaker System
tweeters. You will never
experience the harsh
and damaging distortion
due to clipping.
The Power Guard circuit
is a waveform compara-
tor, monitoring both the
input and output wave-
forms. Under normal
operating conditions,
there are no differences
between the shape of
these waveforms. If an
amplifier channel is
overdriven, there will be
a difference between the
two signal waveforms. When the difference exceeds
0.3% (equivalent to 0.3% harmonic distortion), the
Power Guard activates the PG light and a dynamic
electronic attenuator at the amplifier input reduces
the input volume just enough to prevent any further
increase in distortion. The Power Guard circuit acts
so fast that there are absolutely no audible side ef-
fects and the sonic purity of the music reproduction
Technical Description
Figure 17
Input Test Signal
Figure 21
Block Diagram
of the
Power Supply
Figure 20
Figure 18
Without Power Guard
Figure 19
With Power Guard