What is wrong with negative feedback?


I am not talking about the kind you get as a flaky seller, but as used in amplifier design. It just seems to me that a lot of amp designs advertise "zero negative feedback" as a selling point.

As I understand, NFB is a loop taken from the amplifier output and fed back into the input to keep the amp stable. This sounds like it should be a good thing. So what are the negative trade-offs involved, if any?
solman989
"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.
The Bel Canto ref1000m2 Icepower Class D amps I am using on my larger full range OHM Walsh omnis seem to be able to go as loud as desired without an edge on most good recordings.

These amps are high damping factor which matches well to the OHMs, so I suspect there is NF applied, but not sure. If loudness cues are more present as a result, I'm not sure that it is significant enough to matter.

I also use Triangle and Dynaudio monitors on teh same system. Monitors in general will not fare as well with orchestral music at high volumes (at least not without a sub of some sort to offload much of the work), so I can say that the speakers are definitely a factor as well.
Ralph Atmosphere said, " 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."

I ask do you listen to your system at this level?

Bob