This circuit controls the passage of the signal from one speaker to another. The potentiometers must be of wire 50 to 100 ohms with dissipation according to the power of the sound system.
This simple circuit for the 3 to 30 MHz range was found in the Electronics Experimenter Handbook...
This simple effect circuit for musical instruments and stereos was found in a 1987 publication. Powered by...
This oscillator takes advantage of the 2000 ohms headphone inductance as the oscillator circuit coil....