What is wrong with negative feedback?

Atmasphere,

I suspect it would be hard to set up any meaningful comparison of an amp alone in that an amp cannot produce music alone without speakers. The results could vary widely depending on speakers used, personal preferences, and all the usual culprits that result in different strokes for different folks.

My gut feel is that as you say, its all in the implementation and there are many ways to make tasty soup.

That is true. However I have found the if given the option, people prefer a system that it not bright and harsh, given otherwise that there is no lack of detail, bandwidth and with no tonal aberration.

IOW, a proper stereo should lack loudness cues, such that you can approach the same volumes in your room that the real live music could. A typical orchestra can do 115db with ease, yet many audiophiles will not turn up the volume past 95 db because its 'too damn loud' or they get 'turn that @#$% down!' from their S.O. This mostly due to artificial loudness cues which are totally coming from distorted odd ordered harmonics, and by that I mean only 100ths of a percent.

Its been my contention that negative feedback is a major culprit, literally violating one of the most fundamental rules of human hearing: how we detect the volume of a sound.

Hard to disagree with Ralph's last post in my opinion.

"Its been my contention that negative feedback is a major culprit, literally violating one of the most fundamental rules of human hearing: how we detect the volume of a sound."

Maybe. Maybe not. I've got a Music Reference RM-200II, and there are some compact discs (never records, it seems) in which I can only turn up so loud before my ears bleed, and others I can turn up without any irritation.

Then you factor in the speakers, and their ability to generate clean sound at the levels you are talking about.

Seems to me the only way to make that determination is to take two identical amps, one with negative feedback and one without, and play them with the same source through the same speakers. I've not heard of anyone who has done that exercise, much less anyone who has heard it.

Is the 115dB at a mid-hall seat, or is that the level on the stage? Apparent sound levels in a concert hall are far more influenced by the indirect sound level than in the home environment. This is due to the enormous difference in volume between a concert hall and a normal audiophile listening room (say 200-300 cubic meters vs. 20,000-30,000 cubic meters). In a home environment you listen to predominately direct sound that has nor been tonally shaped (highs rolled off) and homogenized by a concert hall volume of space. Hence it sounds louder than the exact same measured SPL in a concert hall. It really has nothing to do with amplifier design.