DY336 audio preamplifier circuit diagram

The audio preamplifier circuit provides switching signals, volume adjustment, buffering, etc. for the audio, and can add about 10 times the voltage amplification to make the audio have better sound quality.



The circuit uses 3 DY336 low-noise, high-quality op amps. Among them, A1 is used as a buffer follower for the input signal to reduce the burden on the signal source. A2 and RPl form a negative feedback volume regulator. This volume adjustment method can reduce the distortion and noise caused by the change in RPl resistance. Compared with conventional volume adjustment, the transient distortion is smaller due to the lack of the integral effect caused by the RC constant. A3, VTl and VT2 form the output stage, which works in a single-ended Class A state. Its single-ended output contains even harmonics, which makes the sound quality better, and the current driving force of the transistor output is strong. When paired with the back stage, the low-frequency control will be more ideal. The circuit shown in the figure is one of the amplifier circuits of the pre-amplifier (the other one is the same)