Are cryo'd tubes always better?

This is only "my" take on cryoed tubes. I have the same tubes from the same supplier, one pair is cryoed, the other is not. Same batch codes, same date codes ordered at the same time. I can't tell the difference.

So when I buy tubes now, if they are cryoed already, cool. If not, I won't pay extra for them.

Again just my opinion, YMMV.

Always? Dunno, but from my experience with a couple small 9pinners, the cryoed version was 'better' or more to my liking than the non-cryoed versions. Batch numbers were not closely matched so it coulda' been just due to sample to sample variations.

YMWV

Cryo improves the performance of almost all materials, glass, plastics, metal, etc.. However, I think it wise to wait at least a few days, maybe as long as a week, before listening critically to allow the cryo'd material to recover from thermal shock.

At the risk of pissing off half of the people who read this thread, here is my two cents worth:

As one with an extensive educational background in molecular crystallography and metallurgy, I have to say that IMO almost all of the claims and "scientific" explanations made by the cryo vendors are pure BS. Exposure to extremely low temperatures will almost always cause a weakening of the structural integrity for most metals and alloys. One of the guys I went to school with worked for NASA and NAA on the Space Shuttle project, and later on the initial planning for the ISS. Anyone who believes that cryo is universally good for any commercial metal structure should read some of the white papers and technical information that is available to the public.

But for those who insist that science has no relevance for audio and that it is all about the sound, for myself I cannot hear any difference between similar tubes, cryo treated and untreated (beyond the variation one would expect between any similar tubes). But if it's good for you, then it's good.

Actually, cryogenically treating materials improves their strength, hardness,
durability and stiffness, making them less brittle. The improvement to the
material is due to the atomic structure becoming more homogeneous,
especially for metals that have pressed, bent, drawn or hammered. Thus,
cryo 'd tools last longer, cryo'd golf clubs hit the ball farther, cryo'd brass
musical instruments ring less and sound better, cryo'd Ferarri piston rods
last longer, and the valves on cryo'd trumpets move more smoothly. Put
succinctly, cryoing is cold tempering. Heat tempering obviously also
improves the strength and hardness of metals.

Cheers