Controls
Front Panel
The POWER switch turns the unit on and off.
The SOURCE switch is a three position toggle. In MIC mode the microphone input is engaged
and a Jensen mic input transformer is inserted to the signal path before the input stage
operational amplifier. In LINE mode the line input is engaged and a balanced transformerless
amplifier is inserted to the signal path before the input stage. In DI mode the front panel 1/4"
jack is engaged and a high impedance circuit is inserted to the signal path before the input
stage.
The input GAIN knob drives the gain over the op amp in the input stage for all modes (5-40 dB).
The PAD button engages a -20 dB pad with a characteristic impedance of approximately 2300
ohms. This only affects the mic input mode.
The +48 button provides 48V phantom power to the microphone through the XLR connector.
This only affects the mic input mode.
The MUTE button turns the input stage signal to the output transformer off for all input modes.
The PHASE button inverts the signal being sent to the primary side of the output transformer,
inverting the phase of the output signal by 180 degrees for all input modes.
The TRIM knob attenuates the signal after the input module’s output transformer for all modes.
The post-attenuator signal is available at the MIC PRE OUT jack in the rear panel.
The HPF switch is a three position toggle. It can be set to OFF, 50, or 80 for 50 and 80 Hz high
pass filtering, respectively.
Each of the three EQ bands has identical controls. The center frequency for each band is
selected by the six-position frequency switch. The amount of boost or cut is selected by the
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