This simple tone control using two transistors was found in an Electronics Today International of the 90s. Transistors are general purpose NPN types, like the BC549 for greater gain.
This circuit was found in an 1888 publication. However, since it uses common components, it can...
The input impedance of this circuit is about 700 k ohm and the output impedance is about 1 k ohm....
This circuit appeared in the 1991 Electronics Experimenter Handbook. The circuit is for remote...