Yamaha HX-10000 phonostage, any views?

Correction. The vintage Yamaha phono stage I did hear extensively is the C2, not the C1.  Apparently the C1 is an integrated amplifier in their same high end product line.

Theophile, can you refer me/us to actual opinions of the HX10000 phono offered by owners of the unit, to be found on Audiokarma? I can only find one thread in which one guy says he owns one which causes some others to drool with envy. Thanks for any help. Meantime I found one comment on WBF to the effect it sounded “dark” to that listener. I unearthed no formal reviews of it. “Dark” fits with my general impression of vintage SS Japanese gear that the sound is “syrupy”. Of course, my experience is limited, and I’ve never heard the HX10000, although I have heard the Yamaha C1 (I think that’s the model designation for their second best ever phono), and it sounded dark. I remember thinking that I would like to get inside that chassis and upgrade some capacitors and maybe resistors and maybe transistors to see what the C1 could actually do. I think certain pieces of Audio gear, both tube and solid state, both Japanese and American in origin, have become "legendary". And that fact alone artificially enhances our opinion of those items in particular that we've never actually seen or heard and causes us to spend large sums of money in the marketplace, to recapture some magic that maybe isn’t there and maybe in some cases never was. I am certainly not immune to that form of audiophilia, as I own four vintage Japanese direct drive turntables. And I own a pair of Beveridge 2SW speakers from 1980-ish. And the list goes on from there. What I’m saying is that there may be great potential to be developed in the HX10000, but a new owner of an original untampered with example should be aware that there may be work to be done to develop that potential or even to bring the unit up to its OEM peak capabilities.

In my experience with other high end Japanese gear from that era, I perceived a kind of syrupy coloration in their SS designs.While the quality of construction is very high, the sound was usually lacking.  I believe, without having proved it to myself, that the parts quality and function of that era might have been holding back the sound quality.  Since 1987, there has been a marked improvement in discrete transistor technology such that the Yamaha might be hugely improved by judicious substitution of the OEM transistors for new upgraded versions that perform the same function, only better due to faster switching rates, lower noise, etc. It is also possible that performance was negatively affected by the use of electrolytic capacitors here and there in the signal path. If so, it would be beneficial to replace any such electrolytics with film capacitors where possible. So, speaking for myself only, I would view the Yamaha preamplifier as an interesting project, probably not something that I could pop into a system and immediately fall in love with.  Then too, there is the matter of identifying and replacing any electrolytics that may have become leaky over the 40 years since the unit was built. Modern electrolytics are also much better now than they were then.