OPERATION: GAIN CONTROLS
Gain Controls
The gain controls are located on the right side of the front panel. They are operated by rotating the control clockwise to increase gain or counterclockwise to decrease gain. When turned fully counterclockwise, gain is fully reduced and no output signal will be present. When turned fully clockwise, the voltage gain of the amplifier is +26dB and the output signal will potentially be full strength (provided the input is fully driven).
The gain controls are detented in 21 steps for repeatable
adjustment. Surrounding the Gain control, the power | Location of gain controls on the front panel of the CX168 |
attenuation level is shown in dB. Each detent is approxi- |
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mately 1dB change in amplifier gain. |
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To operate the gain control, rotate the control’s knob so that |
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the desired level is achieved. A small, |
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driver (#1 blade size) is typically used. Be sure not to use |
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large screwdrivers as it is possible to damage the gain |
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control by applying excessive torque. Gain controls are |
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sensitive, electronic components and should be treated with |
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care. |
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Each channel pair’s gain controls and indicator LED’s are grouped together as shown, right. The channels are paired in the following manner:
Channel Pair #1- | Ch. 1 and Ch. 2 |
Channel Pair #2- | Ch. 3 and Ch. 4 |
Channel Pair #3- | Ch. 5 and Ch. 6 |
Channel Pair #4- | Ch. 7 and Ch. 8 |
As detailed in the ‘Setup’ section of this manual, channels can only be paralleled and bridged within their channel pair. Example- Channel 3 can be bridged with channel 4 only; it can not be bridged with any other channel.
The dB markings around the gain controls are attenuation. They show attenuation from full gain. At 0db attenuation, the voltage gain of the amplifier is 26dB. If the gain control is set at the 7dB attenuation position, then the voltage gain of the amplifier is 19dB (26dB - 7 dB).
Typical
Typical gain control showing attenuation level markings and LED’s for the channel. Note that there is only one BRDG (bridge) and one PAR (parallel) indicator per channel pair.
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