First Watt SIT-4 Power Amplifier

The SIT-4 amplifier from First Watt utilizes high-grade Static Induction Transistors, continuing the technical ideals and construction of the groundbreaking SIT-1, 2, and 3 designs. An important difference in the SIT-4 is its SIT device, with the previous designs using Silicon Carbide to create a custom vertical power Jfet that mimics the character of a power Triode tube. Unlike its predecessors, the SIT-4 utilizes an industrial SIT with a low impedance Drain, lending itself to superior audio performance with simple Class A circuits and minimal reliance on active circuit elements or negative feedback. The SIT-1 and SIT-2 only required passive elements or a current source for bias, while the SIT-3 utilized a unique Pass circuit, MUFF (Mu Follower/Follower), to bias its Common Drain design. The SIT-4 continues this trend with a Common Source design, but employs a heavy-duty Tokin THF51