How to Operate
How to Operate
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 opera-
tion, rotate the power switch to the On or Off position as desired. Refer to figure 8.
Note: There must be a power control connection between the MC2301 and the McIntosh Control Center,
in order for the remote powerFigure 8
Meter Selection
Rotate the meter mode switch to select the meter operation mode you desire. Refer to figures 9 and 10.
Lights Off - Meter lights are turned off and the meter will contin- ue to indicate the power output.
Note: When Power
Control Input of the MC2301 is connect- ed to a McIntosh A/V Control Center or Preamplifier with Remote Meter Illumi- nation Control, the Meter Illumination will automatically be remotely con- trolled (On/Off) with the METER Switch set to the WATTS or HOLD position.
Watts- The meter responds to all the musical infor- mation being produced by the amplifier. It indicates to an accuracy of at least 95% of the power output with only a single cycle of a 2000Hz tone burst.
Figure 10
Hold - The meter pointer is locked to the highest 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 pointer 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 approxi- mately 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 (Bal- anced) or UNBAL (Unbalanced) Input. Refer to figure 11.
Standby/Protection Indicator
The MC2301 Sentry Monitor Tube Protec- tion Circuitry provides protection to the Power Amplifier in the event of an imped- ance mismatch1 between the MC2301 and
the Loudspeaker. It will also activate if
there is a short circuit at the MC2301 Output Terminals (or the Loudspeaker Terminals) or if a MC2301 Power Out- put Tube should fail. During normal operation 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 Standby 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 Circuitry place the POWER Switch to the OFF position. After wait- ing approximately one minute, place the POWER Switch to the REMOTE or ON position.
1This can occur when a Loudspeaker of a given impedance rating is connected to the MC2301 Output Terminals 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 Loud- speaker at low frequencies where the greatest amount of power is required.
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