What amps do Electrical Engineers own...why?

Thanks, Rok2id. I wasn't intending to avoid the issue.

If we restrict the question to solid state amps, offhand I can't think of any having really poor specs that nevertheless provide top-notch sonics, but there are many renowned high quality amps whose THD and damping factor specs are not **as good** as those of many inexpensive mass market-oriented receivers and amplifiers. Ayre and Pass Labs are just a couple of the many such manufacturers that could be named. Those amplifiers typically use minimal or no feedback, and are able to avoid the use of greater amounts of feedback as a result of the use of high quality parts, and design approaches that are less constrained by cost considerations than in the case of the inexpensive equipment I referred to.

Regards,
-- Al

Almarg,
Thanks for your well written lucid explication. You have sent me back to the books. :) I am beginning to understand the downside of negative feedback. I always knew it was required to control distortion, but there seems to be a better (more expensive) way. I have found some good internet sites that go into detail as to why lesser amounts of feedback is desirable.
Your post is one of the few that has explained WHY high-end amps cost more and should sound better. Now all I need to do is find an 'affordable' amp that meets that criteria.
Thanks for the reply.
As pertains to all my previous posts: never mind.
Cheers

A lot of people would like to think so. Reason being, The Mona Lisa is art, so is some guy throwing buckets of paint at a canvas in NYC. Some people feel comfortable with that situation. Everything is Valid.

The term "everything is valid" could easily be substituted with "everything is subjective" and opinion based, which it is in art and as we see quite often in this hobby. Where I think things tend to get confused is when some of the creative marketing of audio products (not to mention that in other industries) foresakes the very obvious technical and engineering explanations in favor of "audiophile approved" superlatives, adjectives, and general marketing spin.

We saw a good example of this earlier in the thread when transformers were positioned to create a tube like sound. Turns out there was a very good technical explanation of this. However, would that technical explanation be considered a good marketing move when promoting a product?

I'll get to the negative feedback thing later. Suffice it to say I think there is a place for it and it does show up in tube designs as well from some very reputable manufacturers.

If we restrict the question to solid state amps, offhand I can't think of any having really poor specs that nevertheless provide top-notch sonics, but there are many renowned high quality amps whose THD and damping factor specs are not **as good** as those of many inexpensive mass market-oriented receivers and amplifiers.

Al, I think I know of an example, but its not a high-end amp, although it is highly regarded. The example is the old Sunn Concert Lead guitar amp. As a transistor amp its specs were terrible compared to the competition. But it was highly regarded because as a transistor amp it had a lot of the smoothness of tone that you otherwise only got from tubes.

The way the amp did it was to run an all-FET front end (preamp) that was zero feedback. Then the power amp was 2 single-ended gain stages that drove a transformer that did the phase splitter function for the output transistors.

As you can imagine, the primary distortion component was the 2nd harmonic. It made a lot of it! But that gave it a lusher sound that was lacking in its transistor competition (and still is), and so allowed Sunn to make a transistor amp the guitarists actually liked (most rock guitarists play tube amps because they have better sound).

IOM this is a good example of how topology influences distortion characteristics and also how that topology can thus interact with the human ear. IOW how an amp can sound better, and have terrible specs :)