Cryo Treatment: does it provide improvements in sound or longevity?

The pair of CryoTone 12au7 tubes i ordered for the input positions in my Primaluna 400 preamp are supposed to arrive in a few days. They will be competing with the current pair of Brimar CV4003's from Upscale Audio. These tubes are no slouch, so it will be interesting to see how they compare.

The shipping delay was apparently due to an upgrading of equipment at the factory

One would have to assume that any verification of process would have to come from a third party inspection or process monitoring. Doubt that is included with the tubes.

"@faustuss but you’re now one of us with your 234 responses since March of this year, as well as your multiple virtual systems - “you people” now includes you my friend. Too much of your time has been invested into this site that you now dislike.

Let your hair down and continue to mingle on this website that looks and functions like it’s from 1999. Pockets of new knowledge are always found when looking over posts that may seem regurgitated."

Lovely systems @toro3, beautiful home! Love your dog, is he/she a rescue?

"Love your dog, is he/she a rescue?"

Sorry @toro3, didn't see the caption. Stole your heart!

Mullard Cryotubes

I'll take those one at a time....

I can provide the fact my Mother worked for Mullard (Blackburn) in the 1960s and 1970s on dedicated valve lines that used cryo treatment to Mil-spec valves - then I worked for Philips Electronics for over 12 years and learnt of the work they did (in conjunction with Amperex) to produce cryo valves for the Dutch Navy and Air force in the 1950s, 10960s and early 1970s

Annoyingly, documentation for what was once regarded as classified information is thin on the ground - but the many reference charts and booklets that outline the use of Red, Green, Black and Yellow paint to Mil-spec and Med-spec valves to denote improved design, rare metals and cryo treatment is evidence you'll have to take (or not take)


Thank You....and you too

@faustuss appreciate the kind words! Correct in stealing my heart. She’s 13 now…kind of wish time could slow down to avoid the future.