Headphone Driver. The left channel input goes to the top of a duo ganged 100 k ohm audio taper pot. The bottom end is grounded. The wiper goes to the negative end of a 1 microfarad 25 volt electrolytic capacitor. The positive end goes to the noninverting input of one of the op amps in the circuit. The noninverting input goes through a 330 k ohm resistor to ground. The noninverting input also goes through a 10 meg ohm resistor to plus 12 volts. The output of the op amp goes to the base of a 2N3904 transistor. The collector goes to plus 12 volts. The emitter goes to the inverting input of the op amp. The emitter also goes to the anode of a diode, 1N4148. The cathode goes to the transistor base. There is a 100 pf capacitor in parallel with the diode. The emitter also goes through a 30 ohm resistor to the tip connection of a stereo phones jack. The wiper of the pot, same pot, also goes to the positive end of a 1 microfarad 25 volt electrolytic capacitor. The negative end goes to the noninverting input of the other op amp. The noninverting input also goes through a 330 k ohm resistor to ground. The noninverting input also goes through a 10 meg ohm resistor to minus 12 volts. The output of the op amp goes to the base of a 2N3906 transistor. The collector goes to minus 12 volts. The emitter goes to the inverting input of the op amp. The emitter also goes to the cathode of another 1N4148 diode. The anode goes to the base. There is a 100 pf capacitor in parallel with the diode. The emitter also goes through a 30 ohm resistor to the tip connection of the phones jack. The right input goes to the top of the other section of the duo ganged pot. The wiper goes to a circuit which is identical to the one described above. The output of this second circuit goes to the ring connection of the phones jack. The sleeve of the jack goes to ground. End verbal description.
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