Pioneer GM-X924 Service Manual - Page 29

8. OPERATIONS AND SPECIFICATIONS 8.1 OPERATIONS - GM-X1024/X1R/UC Setting the Unit Gain Control Adjusting the gain controls A and B will help match the output of the car stereo to the Pioneer amplifier. Normally, set the switch to the "NORMAL" position. If the output is low, even when the volume of the car stereo is turned up, turn these controls clockwise. If there is distortion when the volume of the car stereo is turned up, turn these controls counterclockwise. • If you only use one input plug, set the gain controls for speaker outputs A and B to the same position. • Set the gain control to "NORMAL" when this amplifier is connected to a Pioneer car stereo with RCA output jacks. If the sound level is too low or distorts, adjust the gain control. • Adjust the gain control to the "MIN" side of "NORMAL" when this amplifier is connected to a Pioneer car stereo (High voltage output type). Cut Off Frequency Control If the LPF/HPF select switch is set to LPF or HPF, you can select a cut off frequency from 50 to 120 Hz. Power Indicator The power indicator lights when the power is switched on. GM-X1024,GM-X924 RCA Input Select Switch For two-channel input, slide this switch to the left. For four-channel input, slide this switch to the right. LPF (Low-Pass Filter)/HPF (High-Pass Filter) Select Switch Set the LPF/HPF select switch as follows according to the type of speaker that is connected to the speaker output connector and the car stereo system: LPF/HPF Select Switch LPF (left) OFF (center) HPF (right) Audio frequency range to be output - 50 to 120 Hz Full range 50 to 120 Hz - Speaker Type Sub-woofer Full range Full range Remarks Connect a sub-woofer. Use if you want to cut the very-low-frequency range because it is not necessary for the speakers you are using. 29