McIntosh MC2KW Owner's Manual

22
Technical Description, con’t
tions. The different types of protection circuits incorporated
in the MC2KW Power Amplifier insure a long and safe op-
erating life. This is just one of the many characteristics of
McIntosh Power Amplifiers that make them world famous.
The MC2KW Power Amplifier also includes the unique
patented McIntosh Power Guard circuit. Power Guard
eliminates the possibility of ever overdriving the amplifier
into clipping. Refer to figures 23, 24 and 25. An overdriven
amplifier can produce both audible and inaudible distortion
levels exceeding
40%. The au-
dible distortion
is unpleasant to
hear, but the in-
audible ultra-
sonic distortion
is also undesir-
able, since it can
damage valuable
loudspeaker sys-
tem tweeters.
You will never
experience the
harsh and dam-
aging distortion
due to clipping.
The Power
Guard circuit is a waveform comparator, monitoring both
the input and output waveforms. Under normal operating
conditions, there are no differences between the shape of
these waveforms.
If an amplifier
channel is
overdriven, there
will be a differ-
ence between the
two signal wave-
forms. When the
difference ex-
ceeds 0.3%
(equivalent to
0.3% harmonic
distortion), the
Power Guard ac-
tivates the PG
light and a dy-
namic electronic
attenuator at the
amplifier input
reduces the input
Figure 23
Input Test Signal
Figure 24
Without Power Guard
With Power Guard
Figure 25
volume just
enough to pre-
vent any further
increase in dis-
tortion. The
Power Guard cir-
cuit acts so fast
that there are ab-
solutely no au-
dible side effects
and the sonic pu-
rity of the music
reproduction is
perfectly pre-
served. The
MC2KW 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 conserva-
tive design.
Power Supply Circuits
To compliment the fully balanced design of the MC2KW
Power Amplifier there is a high current, high voltage power
supply inside each of the MC2KW Power Modules. The
very large Power Transfomer has a toroidal windings on a
toroidal core. Refer to figure 26 (the golf ball is for size
comparsion). It is enclosed in the legendary McIntosh Pot-
ted Enclosures and weighs over 26.6 pounds (12.06kg).
The super size main filter capacitors can store over 430
Joules of energy necessary for the wide dynamic range that
Figure 26

McIntosh MC2KW Specifications

General

Brand	McIntosh
Model	MC2KW
Category	Amplifier
Language	English