Audio Controls - Boss Audio Systems 638B User Manual

Front panel controls

AUDIO CONTROLS

EQ Press repeatedly to cycle through five modes: POP M, ROCK M,
CLASS, FLAT M or DSP OFF.
SUB Press and hold to engage subwoofer output.
LOUD Press this button to increase the level of bass output.
8
MUTE Press to silence the receiver. Press again to
return to normal operation.
SOURCE By pressing this key, user can select AUX/TUNER/CD-
MP3/USB or MMC/SD mode.
AUDIO BUTTON and ROTARY CONTROL Press the button repeatedly to
access Volume, Bass, Treble, Balance and Fader functions. Then use the
knob to adjust the selected function.