MPA-200 Stereo PA Amplifier (320-3003) Operation Faxback Doc. # 14634 TURNING POWER ON 1. Turn on the audio source equipment (such as a mixer or a preamplifier) connected to the amplifier's input jacks. 2. Set the amplifier's LEFT and RIGHT OUTPUT LEVEL GAIN controls to their minimum levels. 3. Set POWER 0/1 to 1 to turn on the amplifier. USING THE POWER METER The position of the meter's pointer indicates the output power. The meter's built-in lamp lights to make the meter easy to see in dark areas. USING THE METER RANGE SELECTOR When output power is too strong, the meter's pointer might continuously swing to the extreme right and damage or reduce the accuracy of the meter. To protect the meter, you can use the METER RANGE selector to control the amplifier's sensitivity to the input power signal. Push in METER RANGE to maintain a 0 dB gain for the meter. When output power is not strong, leave the METER RANGE switch in the out position to allow a 20 dB gain. USING THE LEFT AND RIGHT OUTPUT LEVEL GAIN CONTROLS Rotate OUTPUT LEVEL GAIN clockwise to increase, or counterclockwise to decrease the output power. To get the best performance with the least sound distortion, always adjust OUTPUT LEVEL GAIN so the meter's pointer does not continuously exceed the extreme right of the meter's scale. CAUTION: You can overdrive the amplifier by setting OUTPUT LEVEL GAIN too high. USING THE CLIP CIRCUITRY Continuous excessive output power can distort the sound, cause a thermal overload, and damage equipment. The special CLIP circuitry protects the amplifier and your speaker system from being damaged by overdriving power. Under normal conditions, the amplifier's clip indicator flickers as the output power briefly exceeds the level as set by the output level gain selector. However, under excessive output power conditions, the clip indicator lights steadily to alert you as the special clip circuitry turns on. When this happens, simply rotate the appropriate output level gain control counter- clockwise to reduce the output power level. USING THE A/B SPEAKERS SWITCH You can push in either SPEAKERS A or SPEAKERS B, one at a time, to listen to only the desired channel (A or B) speakers. Or, you can push in both SPEAKERS A and SPEAKERS B at the same time, to listen to all the speakers. Push out SPEAKERS A or SPEAKERS B or both to disable the speakers on one or both channels. Caution: If you speaker's impedance is 4-ohms, do not use both the SPEAKERS A and SPEAKERS B terminal at the same time. (/all-04/20/95)