※ high-grade aluminum 2U black drawing panel, nice; ※ double-sided PCB board technology, components attached to a stronger, more stable performance; ※ new copper transformer, power is more powerful, more efficient; ※ with RCA socket, XLR jack, the interface more flexible; ※ with 100V, 70V constant pressure output and 4 ~ 16Ω constant resistance output; ※ output volume can be adjusted; ※ 5 unit LED display, easy to observe the working state; ※ has a perfect output short circuit, high temperature, overload, DC protection; ※ cooling fan temperature control start;