100W Class-A//AB Amplifier

Posted on Dec 22, 2012

A Class A // Class AB amplifier rated 100 Watts when driving a 4 ohm loudspeaker. This circuit developed out of my 30+ years of JLH class-A based investigations. The original `simple` 1969 JLH class-A design provided excellent first cycle accuracy through mid and high frequencies (dynamic clarity) because there were no stabilisation components nor a series output choke, whilst the NFB error correction was established via the input emitter (some describe this as current feedback).

100W Class-A//AB Amplifier
Click here to download the full size of the above Circuit.

However it did generate rather a lot of heat, the damping was `soft` at lower frequencies and the positive slew was weaker in the presence of loudspeaker system generated back-EMF at higher audio frequencies. I was eventually able to improve upo

Leave Comment

characters left:

New Circuits



Popular Circuits

Flashing Lamps
Color Sensor circuit
Battery charger
RS232 transceiver circuits
Quiz Project
simple frequency counter circuit
propeller receiver
Three circuits of preamp tone controls by NE5532
CO2 Laser
ultrasonic transmitter
Asynchronous power wiring diagram
Noninverting gain circuit diagram by the MAX4107