Please use a linear power supply, the ripple is small, and it is not easy to generate hum.
Stereo o two-way input four-way output, can directly push four headphones or external power amplifiers do not affect each other, power supply.
the nification is about 5 times, the potentiometer controls the volume of each output separately.
Using the high-current op amp NJM3414A from Japan JRC, the maximum output current is 70ma, which can provide good large dynamic fidelity output.
Material:plastic.