The Singing Machine SML633 Instruction Manual page 14

Operation
Playing Songs from the USB (Continued)
X
U
6
Connect microphone(s) and
slide the ON/OFF switch on the
microphone to the ON position.
V
7
Adjust the MIC 1 or MIC 2
VOLUME control as desired.
W
Increasing this will increase the
volume of respective microphone.
8
AUTO VOICE CONTROL can be
activated by rotating the AVC
control. The higher this control is
set to, the more the vocals on the
multiplex recording will be muted
when the singer starts to sing
through the microphone. When
the singer stops singing, the
recorded vocals on the multiplex
recording will resume to normal.
9
Rotate the BALANCE control
clockwise to hear the music and
recorded vocals from a multiplex
recording or counterclockwise
to hear the music only from a
multiplex recording.
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