Agreed I don't know anyone one using caps in the signal path in amps anymore. In fact, when I was doing my senior level design project for my undergrad, my teacher made me design a level shifting circuit as he wouldn't allow me to use a blocking cap
When I see pure nonsense in the ad puffery, and a high price tag, I sense a wallet biopsy not in the customer's interest.
From their description of the bias altering with load, it sounds like standard A/B biasing to me.
If they have something new to offer then they should publish the circuit and the math for peer review. If it is different enough to get a patent they have nothing to fear, of they can't it doesn't matter.
Peter published everything for peer review before going to market. His feed forward design was not a hole in one, that is why there are so many iterations of the 405 and 405-2. In those amps, the slew rate never was high enough to allow full power at the top end of the frequency spectrum. That had to do with stability issues. However as Peter pointed out, music does not require full power at the top end. If it did we would all be blowing tweeters. After the 405 series this issue was solved. However, later iterations of the 405-2 are excellent sounding amps.
By the way, all his owners manuals contained a full circuits and voltage points. How things have changed!
I have 3 KW of power here using current dumping amps, for less than the cost of the cheapest model of those "ibias" amps, whatever that is. If this is something new and in the customers interest, Krell need to step up the plate and let the designers explain and send the marketers home. Until then I have no faith in anything they have to say about these amps.
