This circuit is from an Electronics World of 1968. The transistors are of the time and the power is supplied with a voltage of 40 V. The circuit is high fidelity.
This amplifier from 100 to 150mW was found in a Japanese documentation from 1967. The circuit uses...
This circuit is from a manual of JFETs and can be implemented with the BF245 and for the bipolar...
This source of some amps for voltages up to 40 V was found in an Italian magazine Elettronica...