McIntosh MC-7300 Brochure

MC73OO

Power Amplifier

The Mclntosh "Always In Style"

TIMELESS LOOKS
PEAK PERFORMANCE
OPTIMUM DEPENDABILITY
CLASSIC DESIGN

The classic appearance of a Mclntosh amplifier
complements any home decorative scheme. Each
component is selected for durability, as well as
aesthetics.

Consider the construction and materials used in
the front panel and knobs. Reverse silk-screened
with thermal setting epoxy screen inks, the glass

panels are meticulously hand inspected and are
free from bubbles, flow marks and other faults.
Anodizing, an electro-chemical process that leaves
a color dyed and hardened surface impervious to
attack from common household cleaning fluids,
oils and acids from the skin, is used on the panel
frame and aluminum knobs to maximize their
resistance to wear.

This handsome combination of glass, anodized
aluminum, and thermal setting epoxy inks requires
very little maintenance to keep the MC7300 look­ing brand new. Its subtle yet sophisticated styling
will

remain

in

good

taste

throughout

the

years.

(safe operating area). The power transistor
characteristics, the power supply voltage used, and
the output autoformer ratio have been matched for
high efficiency, maximum power output with low
distortion, and reliable long life operation.

Versatile Mclntosh Power Amplifiers
Deliver Full Power — Always

The Mclntosh output circuit, superior in its perfor­mance, demands a superior method of coupling
the amplifier output to the loudspeaker load. A

Mclntosh designed and manufactured
autotransformer ensures peak performance and
protection, as well as outstanding compatibility
between amplifier and speaker.

The Mclntosh autotransformer offers these benefits:

• Transistors, used in amplifier output circuits, are
designed to work into an optimum low im­pedance load. Variations in frequency, or the use
of multiple speakers (which modify the im­pedance as seen by the output of the amplifier),
often compromise an amplifier's performance.

The Mclntosh autotransformer prevents these
variables from causing restricted performance,
output transistor heating, and/or circuit failure.

Rear view

Mclntosh Quality Begins With Careful
Design For Cool Operation

An

amplifier's
per ventilation for cool operation. In fact, as little
as one degree centigrade rise in temperature can
reduce the life of an amplifier by 10%. Mclntosh
has designed its amplifiers to maximize trouble­free cool operation.

Output stages are mounted on super-sized heat
sinks that have maximum surface areas of cooling
capability. The sinks are placed in an air tunnel
chassis that occupies the amplifier space from top
to bottom. Cooling air, which flows through the air
tunnel, dissipates life-limiting heat. This heat
dissipation capability is coupled with a chassis
construction that encourages ventilation. A Mcln­tosh designed and manufactured autotransformer
matches the transistor output circuit to the
loudspeakers.

The Mclntosh output circuit uses 20 metal cased
bipolar epitaxial power transistors and 4 metal cas­ed driver transistors. The output transistors feature
high fT (gain - frequency product) and large SOA

life

can be cut

short

without

the

pro-

• In the event of an output circuit failure, the
Mclntosh autotransformer conducts the speaker-

damaging DC (direct current) directly to ground,
thus protecting expensive loudspeakers from

potential damage.

• The Mclntosh autotransformer contributes a flex-

ibility in loudspeaker connecting capability not
otherwise possible. Here's how:

Ordinary amplifier output circuits are usually

restricted to operating in 4 or 8 ohms. In stereo,
the Mclntosh autotransformer perfectly matches
the output circuit to 2. 4, or 8 ohms. In mono
the MC7300 autotransformers provide matching
into 1, 2, 4, 8 or 16 ohms. In addition, the
autotransformer can provide either a 25 volt or a

70.7 volt output that can feed multiple
loudspeakers for background music applications.

Heat sinks