Best cost no object tube phono

Here’s a 22 tubed unit. Lots of reviews on the web here's some discussion in these forums. We'll under $10000.
https://forum.audiogon.com/discussions/review-new-valve-order-spa-ii-tube-preamp

There are a few threads on this. As Raul points out it is very difficult to get very low noise in an all tube phono stage.

Difficult but not impossible. To get low noise with tubes you do some of the same things that are done in solid state preamp- particularly those that have opamps:
1) have a tightly regulated power supply2) use differential inputs3) use effective constant current sources for those differential circuits
In addition you simply parallel tube sections as part of your means of reducing noise.

The reason differential gain stages are used in solid state (and in some tube phono sections) is that for every stage of gain that is differential, theoretically you get 6dB less noise. This adds up- if you have two stages of differential gain, that's 12dB lower noise. But to that theoretical limit the constant current source really has to work.


If you do this then its no worries getting a phono stage to work fine with a cartridge of 0.2mV with gain to spare.

@atmasphere 

I would be interested to know with paralleled tube circuits, how can you ensure the tube sections parallelled are matched, and stay matched over a reasonable time. If they are not perfectly matched, then I would assume smearing of signal occurs.

This solution is not cost no object (cost always matters;). It is a non-plus ultra scenario for realistic people. Perhaps the best designed phono stage that had more thought put into it than money-oriented no object designs. Adding the SUT will just kick dynamics into a whole new gear.. their combination is just superb!

I see this path as a straight ticket to audio heaven: Expressive Technologies step up transformer + Hagerman Violin phono stage (tubed, with choke input dual power supplies and separate filament supply. You can choose between 4 RIAA curves, and it has polarity switch, so listening in correct polarity is not an issue anymore). The Violin is an extremely unerrated phono stage, never got fame because Jim sold it waaaay under its performance value. He had to stop making it because he did not break even. Still, the price tag was not cheap, but it was what the unit packs... opposed to "cost no object pricing", inflating the real value by a factor of x10 - x20, and spending more on a shiny chassis than for the goods and technology contained. Just a sad fact of life...I’m always on the look out for "thought no object" designs, where there was serious thought about realistic performance, instead of breaking barriers on unavailability. 

Adding the SUT will just kick dynamics into a whole new gear.. their combination is just superb!

Low gear. SUT's have phase shifts that vary across the frequency spectrum. They cannot preserve accurate time & phase relationships across the full frequency spectrum accurately. They can achieve high gain/low noise, but they cannot preserve speed and coherency. Their endemic phase shifts and colourations provide a rose tinted view of the world, but not accurate reproduction of the signal.