The Singing Machine SML2082BTBK Instruction Manual page 17

Operation
Using the LINE IN Jack (Continued)
6
7
6
7
8
6
Press the MIC VOLUME + or –button
as desired, which will affect both
microphones.
7
Press the ECHO + or – button to add
an echo effect to your voice.
8
Press the ON/OFF button to turn the
unit off.
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