Amplifier classes

Thread Starter


Joined Mar 24, 2008
One of the thoughts that have been going though my head is a series of articles going through the various types of analog amplifiers for the experiments section. I also notice they are not described in the early parts of the book, which means it is wide open for a contributor.

The amplifier types I was thinking of were:

Class A
Class AB
Class B
Class C
Class D

I have already made a significant start on the class D as part of my 555 articles.

One of my thoughts is if anyone has a simple schematic they would like to contribute I'll pretty it up for the book, test it out, and give full credit to co-contributors. The goal with these schematics is uber simplicity, so something like 2N2222A and 2N2907A transistors preferred. Something like Mr.Chips preferred parts list is a good start.



Joined Apr 28, 2013
Sounds really good and would like to help out (not sure how much of a help I could be with no experience) ...Also this will help out with alot of threads as to regards with amplifcation...


Joined Dec 13, 2013
clas a amps are biased on all the time and amplify 100 percent of the wave. very linear amp, poor power efficiendcy.
class b amps are biased right at cutoff, usually push pull, and amplify 50% in pushpull, they dont draw any power and have good linearity for audo amps.
class ab amps are biased with a little current flow on no signal and work as linear amplifiers for rf.
class c is biassed into cutoff, only conducts for a small portion of the wave, very bad linearity for audio, and very good efficiency for rf amps.


Joined Apr 5, 2008
Hello Bill,

There are some more amplifier classes.
There is also class I, wich is like PWM, but with two drivers.
One for raising the signal and one for lowering the signal.

In RF techniques you also have class D,E and F:

All link come from this EDUCYPEDIA page on amplifier classes: