The cut-off frequency of the circuit shown in the figure is 750 Hz, with the components used. The circuit applies to almost any operational amplifier and the power supply must be symmetrical.
We found this circuit in a 90s 73 magazine for radio amateurs. The circuit has 3 W of power and can...
This circuit is from old American documentation, but the transistor used is still very common...
This circuit uses a simple power source, having been found in the Philips Databook of 1990....