What makes an amp Class A, A/B etc,

Thanks Mark

So Class A has the most power consumption and operates ineffeciently but carries the ? cleanest or least distorted? signal without feedback. or is that too simple.

Also is this related to feedback at all or is that another aspect of amp design.

I have also heard of class d amps.
Are there any references that explain these types of terms as well as push-pull, balanced-unbalanced, feedback and the like

It is a lot to fathom, an idiots guide to amplification theory is what I need !!
if you will!

Thanks again Mark

Groovey Records

Listening to

Thelonius Monk Genius of Modern Music Vol 1 Blue Note BST 81510
Direct Metal Master Pathe Marconi Digiatal Remaster Vinyl

Dear groovey: Feedback is a different subject.

Now, a class A amplifier design it is not always better than a class AB or B design operation. I heard over the time some class A amps that sounds not so good and AB that are really fine, all depends on the whole amplifier design and not only if it is class A/B/D/etc.

Regards and enjoy the music.
Raul.

Markphd- a furhter definition of CLass AB is that it runs in class A for the first watt or so where most of the music is.

Vacuum Tube Technology Overview

The basic purpose of the audio amplifier is to increase the current, voltage or power of a signal and deliver the signal to the speakers. The three basic types of amplifiers are solid state, hybrid (utilizes tube and solid state) and vacuum tube. Each technology has its positives and negatives. Although the general operational characteristics of the three audio amplifier types are similar, there is a differential in the sound.

There are two basic designs of tube amplifiers. One design is the triode amplifier (also referred to as single ended or Class A) in which one vacuum tube (300B, 2A3) is used per channel to amplify the audio signal. Within the tube, a small signal is placed on the grid which causes a large fluctuation of voltage. Thus, the small amount of signal controls the larger power so that the signal is replicated at a larger level of energy. Another design is the push pull amplifier (Class AB). Rather than using one tube, the push pull amplifier uses more than one tube per channel. One tube will amplify the positive portion of the signal and the other tube will amplify the negative portion. The push pull design provides greater wattage than the single ended amplifier. This is a very simplified rendition of how a tube amplifier works. For the detailed technical operations of audio amplifiers, we recommend engineering web sites.