Beyond Ayre Pass and Rowland

If you are looking for exceptional gear that is exotic, i.e., not the more "common" brands that you mentioned, there are plenty of candidates, not necessarily better, because there are so many factors involved.  I personally would love to hear the solid state gear by BaLabo (Bridge Audio Labs, a Japanese manufacturer); I know someone who has heard a lot of exotic stuff and thought that their gear was very nice for solid state.  I have heard DarTZeel gear that sounded very good in the solid state camp.  At MUCH lower price, I like the First Watt gear made by Nelson Pass when used with suitable speakers (high efficiency, high impedance speakers); I like it more than I do Pass Lab gear.

For the other side, I like Audio Note (both UK and Japan), Viva, Shindo and Ypsilon (hybrid).  I own an Audio Note (uk) Kageki and a Viva fono (phonostage).  I currently run a different amp in my system and a preamp made by the same designer.  That designer/builder is Aldo D'Urso (Italy).  This is, to me, exceptional gear, but, it is pretty much custom-made and not at all easy to find.  I also like the Epifania linestage (I still own one) made by Fred Voltz of Emotive Audio, but, I don't think he still builds gear. 

I have heard Constellation, Soulution and Devailet, FM Acoustics, etc., but not in my own system and none of these really perked up my ears and made me interested.  

No-one mentioned Halcro and Boulder. I am not familiar with them. Where do they stand?

I've heard some Boulder amps & preamps. the one that i remember - in the preamp there was optical coupling & the power amp was some 2' deep (maybe even deeper) driving Avalon Acoustics speakers. Heard these in a dealer's showroom. Not impressed with the sonics.....

I see. I remember reading similar comments about Boulder.