A while ago after a brief conversation with Slawa re tube rolling, he recommended a 6N6P NOS tube made in the 60's at the FOTON factory
I have obtained a pair (could not find singles) and one of them has sat in my DAC 1 since before Xmas
It leaves the stock one for dead and is slightly better at detail retrieval than my Tesla, although not quite so good at ambient detail. The treble balance is slightly higher but a worthwhile improvement and at about 30 squids for the pair not too bad a price
Lumley Heliosphere Audiomods 5
Voyd Valdi AN Arm 1 V2 and Denon MC
Audiomeca Talisman Highly Modded
Audiomeca Kreatura &,SW1X DAC1
Hovland HP200 MC
Hovland Radia
Ming Da 805 monos
Magnum Dynalab Etude, RWA Cassabria + LCD 3
Wilson Benesch Actors
Cables by Cardas, Hovland G3 and Yter