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Densen B-100, now only available used is a minimalist design with minimal feedback. It sounds great.
Now I've said that I'd also say that I would never buy equipment based on design philosophy, but on how it sounds. Perhaps you'll prefer the sound of an amp with a lot of feedback and you'll never find out.
Ditto Seans's comment. Neg. FB is but one ingredient in the amplifier recipe. Higher FB may better control underdamped bass drivers/enclosures. Most modern amps use little fb anyway. Of greater concern to me would be the spkr/amp interface. One spkr of mine requires high SS power, another pair thrive on low power tubes. Both are valid and very satisfying sonically. But the presentation is miles apart.
I can't agree with the statement above that "Most" present amps use less global feedback. Compared to 20 years ago, yes. Now? Hmmm. For instance, the well respected Parasound JC-1's use 39db. Most would consider this moderate. ALl of the amps you have listed use a considerable amount of NF, both global and some local.
The only amps using NO neg. feedback are the Theta's, Ayre amps and just a very few others. Ayre uses no feedback period.
FB amps do control the bass better but that's about it for sonics. The no FB amps are a little lighter in the bass but more pristine and correct sounding through the mids and highs. NF causes timing issues in the time domain. You are inserting the output signal back into the signal path 180 degrees out. That's a pretty big trade off for what you get but it's also a cheaper way to get a sonically impressive sound for most audiophiles and easier to manufacture.
No, NFB amps aren't for everyone but what is. Each has to decide what is more important to themselves. I find the no feedback amps more to my liking but I also had a Belles amp that had feedback, ran in class B and used Mosfet ouput devices. It sounded very, very good. So, I would have to agree somewhat with the implementation theory. Amplifier design hasn't change much over the years. Most improvements are in literature, from people who own them and but most of all---parts quality and consistency. Look at any amps basic schematic and it looks pretty much like it did 25 years ago!
I built a Hawk Audio A-18 kit and think it sounds great. Can be switched to class A only and uses no feedback for 10 watts per channel, using 4 FET's per side. Easy build, but the stock case is expensive. Just components run about $1K. Talk to the US importer, http://www.hawkaudio.com/ They're very friendly and informative. A review is available at http://www.tnt-audio.com/ampli/hawk_a18_e.html
How do "gain clones" not have global feedback?
The old Threshold stuff did not have a global feedback loop, but did have a local one that encompassed the output stage. As did some older Rowland stuff (Models 3, 5, 7.....maybe a few others.)
The first 2 amps have lots of global feedback.
We have built amps using lots, some, a little, and zero global feedback. We feel the ones without global feedback sound more natural, but there are drawbacks. It all depends on your system, your tastes, and expectations. Only one way to find out...........yep, you have to stick one in your system to find out if you like it.