Simple and applicable "karaoke" power amplifier

 The input resistance of both input terminals of I.M386 is 50kn, and the ground level is close to zero. When two same level signals are added to the
positive and negative input terminals of 1JM 386, these two same signals will be generated inside the LM386. Cancel each other out. The singer's voice in the stereo tape
is evenly distributed on the I, and R channels . After being amplified in the same way, and then adding the two opposite input
terminals of the LM386, the singer's voice can be offset by adjusting the balance potentiometer. RP2 can offset the singing voice to the minimum amount. Since the accompaniment music on the tape
was recorded on the I and R channels respectively, its content and band arrangement are also different between the two channels
, so the accompaniment music can be retained. , amplification output
    When your singing voice is input to the TDA2822 through the MIC.cii, R9 is amplified, and then amplified by the LM386 , the sound can
be emitted through the amplifier along with the accompaniment music.