Your amps are very good looking, much
nicer than anything I've ever built aesthetically, but I don't care much about appearance in my gear.
I am slightly envious of you getting to meet Bob Carver as I've respected him as an engineer for decades, especially for the Stereophool challenge. I would love to speak with him about amp design as I've been working with and designing linear electronics most of my life, both professionally and as a hobbyist.
I did a bit of googling and found this article
on his site. I laughed all the way through it as it reflects a similar approach to the last set of tube amps I designed and built, especially the nested feedback loops, some using grid to plate feedback between stages and about how the 12AX7 (and it's ugly step sister the 12AU7 - my additional comment) are rubbish for high fidelity audio and U/L has never been my preferred choice of output stage topology. Prof Cherry taught me about nested NFB in 1980 and when I showed an old engineer I worked under the plate to grid feedback a few years later, he laughed and said "Hegeman did that in 59, son". Both work a treat when applied correctly, but seem to be beyond the ability of current designers, or more likely design amps to whatever the current trend or fashion in design is, such as SET. Good to see solid engineering is still in use in some circles. Nice to see a lack of name brand boutiquey parts in your amp too.
I'd love to see a schematic of your amp, but I expect it's proprietary.