Stereo Class A Tone Control Circuit Transistor

Class A amp circuits are accustomed for some reason class a tone access control systems never occurred to me that been the performance I am very curious probably a normal tone control circuit based on is much better circuit critical materials 2SA872, 2SD666 transistors on the market Does not know, but there will not like, resistors 1% tolerance is used If the Class A quality solid capacitors and potentiometers think that the exact data

Class A tone control of solid printed circuit schematics and layout drawings are

Class A tone control circuit pcb, schema files: