Specifications

all cases, the leads to and from the speaker should be
twin conductor or twisted together When using 8 ohm
speakers and for the normally short distances of under
30 feet between the amplifier and speaker, No 18 wire
or larger can be used. For distances over 30 feet
between the amplifier and speaker use larger diameter
wire. Select the correct size wire for the wire length
from the chart It is recommended that the DC resis-
tance of the speaker leads be less than 5% of the
speaker impedance. Up to 10% can be tolerated. Resis-
tance of the leads should be computed for the length
of wire both to and from the speaker or speakers.
MAXIMUM WIRE LENGTH
- For 4 ohm Load -
Wire
Gauge Feet Meters
18
16
14
12
10
15
25
40
60
100
4 6
76
122
183
30 5
- For 8 ohm Load •
Wire
Gauge
Feet
Meters
18
16
14
12
10
30
50
80
120
200
9 1
152
24 4
36 6
61 0
Wire lengths above represent the wire resistance
equal to 5% of the speaker impedance
For multiple speaker operations, run separate leads
from the amplifier to the speakers
CONNECTING LOUDSPEAKERS
Connect the leads from the left loudspeaker to the
Left - and + OUTPUT terminals on the MC7100
Connect the leads from the right loudspeaker to the
Right - and + terminals For MONO bridged operation
connect the speaker to the MONO - and + output
terminals
AC POWER
The amplifier AC power cord is plugged into a 120
volt 50/60Hz wall outlet, or into a outlet on the
preamplifier If you wish to control the AC power from
a preamplifier control center, be sure the AC cord of the
MC7100 is plugged into the controlled outlets on the
rear of the preamplifier control center
Power Guard Operation
McIntosh Exclusive Digital Dynamic Protection Circuit
Improved recordings and recording techniques
have imposed higher power demands on today's amplifi-
ers Poorly designed amplifiers can present music
listeners with a form of harsh unpleasant distortion due
to amplifier overload (hard clipping) Clipping, which
looks and acts like non musical square waves, is caused
when the amplifier is asked to produce more power
output with low distortion than it is capable of or
designed to deliver Amplifiers, when driven to clipping,
can deliver up to 40% harmonic and intermodulation
distortion that decreases the pleasure and enjoyment
you get from listening This form of distortion (clipping
signal) also produces extra heat energy which will
damage most speakers Mclntosh leadership in
engineering has developed the Power Guard circuit
which - (1) dynamically prevents power amplifiers from
being overdriven into hard clipping - (2) assures that the
amplifier will produce its maximum output without
increased distortion - (3) protects your speaker from
excessive heating Power Guard is a patented Mclntosh
design (U S patent #4048573)
The MC7100 has a circuit that compares the
wave shape of the output signal to the input signal
If the disparity between the two signals, due to
overdrive, exceeds an average of 0 3% (equivalent to
0 3% total harmonic distortion) an amber POWER
GUARD indicator illuminates With any further increase
in distortion the POWER GUARD circuit operates to limit
the amplifier input dynamically so that the amplifier
cannot be overdriven POWER GUARD eliminates
amplifier output clipping POWER GUARD only operates
when the amplifier is asked to deliver more power than
that for which it was designed
Rear Panel Information
LEFT GAIN
Use the LEFT GAIN control to ad|ust the output
in the left channel to the desired listening level Turn
the control clockwise to increase the output
RIGHT GAIN
Use the RIGHT GAIN control to adjust the output
MclNTOSH LABORATORY INC., 2 CHAMBERS STREET, BlNGHAMTON, NEW YORK 13903
MC7100 Product Preview/Page 3