17
least 95% of the power output with only
a single cycle of a 2000Hz tone burst.
Hold - The meter pointer is locked to the high-
est power peak in a sequence of peaks.
It is electronically held to this power
level until a higher power peak passes
through the amplifier. The meter point-
er will then rise to the newer higher
indication. If no further power peaks
are reached, the meter pointer will
very slowly return to its rest position
or lower power level. The decay rate is
approximately 6dB per minute.
Input Mode Switch
The Input Mode Switch, which is located on the Rear
Panel of the MC2301, allows you to
select either the BAL (Balanced) or
UNBAL (Unbalanced) Input. Refer to
figure 11.
Standby/Protection Indicator
The MC2301 Sentry Monitor Tube Protection Cir-
cuitry provides protection to the Power Amplifier in
the event of an impedance mismatch
1
between the
MC2301 and the Loudspeaker. It will also activate if
Power On
To have the MC2301 automatically turn On or Off
when a control center turns on or off, rotate the power
switch to the remote position. For
manual operation, rotate the power
switch to the On or Off position as
desired. Refer to figure 8.
Note: There must be a power con-
trol connection between the
MC2301 and the McIntosh
Control Center, in order for
the remote power turn-on to
function.
Meter Selection
Rotate the meter mode switch to select the meter op-
eration mode you desire. Refer to figures 9 and 10.
Lights Off - Meter lights
are turned off
and the meter
will continue
to indicate the
power output.
Note: When
Power
Con-
trol
Input of the MC2301 is connected
to a McIntosh A/V Control Center
or Preamplifier with Remote Meter
Illumination Control, the Meter
Illumination will automatically
be remotely controlled (On/Off)
with the METER Switch set to the
WATTS or HOLD position.
Watts- The meter responds to all the musical
information being produced by the am-
plifier. It indicates to an accuracy of at
How to Operate
How to Operate
Figure 8
Figure 9
Figure 10
Figure 11
1
This can occur when a Loudspeaker of a given imped-
ance rating is connected to the MC2301 Output Termi-
nals with a different impedance rating. For example,
a Loudspeaker with an impedance rating of 2 Ohm is
connected the MC2301 8 Ohm Output Terminals. The
impedance of a Loudspeaker actually varies as the
Loudspeaker reproduces different frequencies. As a
result, the nominal impedance rating of the Loudspeaker
(usually measured at a midrange frequency) might not
always agree with the impedance of the Loudspeaker at
low frequencies where the greatest amount of power is
required.
there is a short circuit at the MC2301 Output Termi-
nals (or the Loudspeaker Terminals) or if a MC2301
Power Output Tube should fail. During normal opera-
tion the Sentry Monitor Tube Protection Circuitry has
no effect on the performance of the Power Amplifier.
In the event a problem occurs, the MC2301 Sentry
Monitor Tube Protection Circuitry will activate to
prevent potentially destructive high levels of current
from flowing in the amplifier. The Front Panel Stand-
by LED will start flashing indicating the Protection
Circuitry is active. Refer to the illustration on page 16
for the location of Standby LED.
To reset the Sentry Monitor Tube Protection Cir-
cuitry place the POWER Switch to the OFF position.
After waiting approximately one minute, place the
POWER Switch to the REMOTE or ON position.
