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Line inputs for connection with RCA line-outs of the head-unit.
LEVEL adjustment for channels CH1/2 to match RCA line output voltage.
Slide switch to select Highpass, Bandpass, or Fullrange operation.
Adjusts the cut-in frequency for channels CH1/2.
Adjusts the cut-off frequency for channels CH1/2.
LEVEL adjustment for channels CH3/4 to match RCA line output voltage.
Slide switch to select Highpass, Bandpass, or Fullrange operation.
Adjusts the cut-in frequency for channels CH3/4.
Adjusts the cut-off frequency for channels CH3/4.