What are some favorite NOS 12AX7s for phono?

Stickman 451,

The Tron 7 is a very good stage for the money. I heard it with a Transfiguration Orpheus cartridge and an Ortofon Per Winfield cartridge. Noise was not an issue with either cartridge.

I heard the Hovland HP-200 with the Orpheus and a Lyra Titan. Noise was only an issue when the factory default loading was used. It turned out that the default setting is 100k (essentially unloaded) and the noise sounded like radio frequency interference. With more loading (lower numeric value) noise went away. The Hovland is a very decent phono/linestage sonically. My big issue is that I don't like stepped attenuators with a small number of steps--the "right" volume seems to always be between steps.

My Viva Fono is dead quiet and easily the best of these phonostages. It is vivid, harmonically dense and capable of throwing a huge soundstage. It has also become crazy expensive. The last I heard, it goes for somewhere around $16k. It is also not easy to make loading changes with the Viva. One has to open the case and solder resistors across the RCA input jack (primary side loading of the step up transformer) and that is a touch tricky given the small space and abundance of tiny wires nearby.

I haven't heard the EAR 912.

I know it appears that I only like tube-based phonostages. That is not the case. I think that one of the best stages I've ever heard is a Lyra Connoisseur. This is an extremely dynamic sounding phonostage that does not have the sort of mechanical sounding and artificial hardness to the attack of notes that is often found with solid state phonostages. It is too bad that it is no longer made (not that I could afford one of these).

Thanks to all for many interesting answers with much food for thought. I am going to test the waters with a pair of Dutch Amperex phono selected ECC83; they are the I65 variant and have a "delta" factory code etched. (I'm quoting the vendor here!) I got a good deal on these; not ebay prices but much less than some I have seen. I chose these because of the HUGE amount of praise they receive on every tube forum I logged onto. Perhaps when the Sophia and Psavane tubes get wider circulation and thus are more widely evaluated I can think about trying a new production tube. Again; many thanks. I look forward to posting listening impressions shortly.

I would avoid the 1980s Russian "Rocket"Voshkods 12ax7's. They are usually quite microphonic in my experience. I have some Philips Miniwatts which are identical to the Bugleboys and sound good. I also have experimented with rectifier tubes and found they play a role as well.