Composite Class A Amplifier

It is a pure Class B output CL type power amplifier circuit. The front-end input part of this circuit does not use
the traditional differential input circuit, but uses a composite analog A analog rescue circuit with a single-ended input and a single-ended output. Its
working principle is shown in Figure 2-39. It is a directly coupled two-stage amplifier circuit, and its amplification capability is even greater than the two-stage
differential amplifier circuit. In the circuit, REI.Rl is the emitter resistor , which can be used as a DC negative feedback resistor to stabilize its working
point, and as an AC negative feedback resistor to increase the input impedance of the circuit. To match the preamp. The resistor RE is used to
achieve current sharing between the two tubes VTi.VT2.