Server preamplifier circuit diagram of parallel op amp

The servo preamplifier circuit using a parallel operational amplifier is shown in the figure below. This circuit provides differential output for a 115V, 60Hz servo motor power amplifier. One op amp is connected in anti-phase and the other op amp is connected in phase to form a complementary output circuit. The voltage gain of the circuit is 40dB, and it is powered by a single voltage regulator tube regulated power supply. The circuit uses deep DC negative feedback and has good DC stability. The bandwidth is 60KHz and the input is driven by 90° phase shift.