What could I expect to hear from a Class A amp?

Bearotti, class AB amps usually operate in class A up to some power level. The exact amount will vary from a few milliwatts to several watts, depending on how generous the designer is with biasing of the output stage.

You mentioned a concern with low level listening. The Classé Model Fifteen, when biased to factory spec should deliver about 5.3 watts in class A into an 8 ohm load. That should be enough to keep you in class A for most listening at low volumes with reasonably efficient speakers.

Fabulous descriptions. I have visited this site regularly for a few years now. Had some basic input of my own.

But I'd like to add this.

The people on this site continually help build my audio knowledge with their unreserved pouring out of knowledge. It makes my keen interest in music and my secondary hobby in audio more interesting by the day.

An ongoing thank you to all the folks keeping Audiogon so alive and vibrant. There really is nothing else like Audiogon. Bravisimo!

I do appreciate the technical explanation. On one hand it's about education. On the other hand it builds credibility to one's belief. From what's expressed thus far, can I take it that Class AB has more issues to overcome? The combination of designer skill and his stand on debatable subjects makes it difficult to come up with a comparable sound delivery system. Whereas Class A design is more simple, but with the problem of heat and power consumption.

My second question if I may would be what enables Class A solid state design to incorporate the strengths of tube amplifier concept with less of the problems. Is it because of shared design? Somebody mentioned about 2 tubes and a resistor.

For further and deeper understanding of Class A design and operation visit http://passlabs.com/articles.htm There you can find several articles dealing with Class A and other amplification devices. Well worth the time to visit and read the articles from the man that for all practical purposes responsible for and defined high end in the mid 70s to today.

Nelson Pass when he was at Threshold clearly defined and manufactured some of the worlds best Class A amps and preamps. In 1991 he left Threshold and started Pass Labs and the in the years since these products have further pushed the envelope of Class A design. In my opinion no one does it better than Nelson Pass.

Tubes have their problems too! It's very hard to find good "tubes" that will last like they should "these days". New TUBES can go BAD "at any time"...at any price! That's a BIG Problem.....!