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

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

no, and no.

I designed SS analog circuits, used in large, up to few billion gates SOC (system on chip), to make sure there is no structural damage of different temperature driven materials expansion in whole devices, within storage / operational guaranteed temperature range.

Cryogenic temperature is outside guaranteed storage and operational temperature range, thus it will cause structural damage of tubes, mainly due to difference of TEC (temperature expansion coefficient) of materials used to build a tube! 

nice example of it: 

Great feedback guys. This is what I was hoping for. 

@erik_squires 

That is exactly the kind of thing I was thinking. You do get a bump from wiping all your connections. Not enough, for me, to do it religiously.

You might want to look into Townshend Audio's method of treating copper wires. Their Fractal treatment DOES make a big improvement to my ears. 

I bought the same exact pair of tubes, one pair cryo'ed and the other not.  The pairs were matched as close as possible, well within +/-1% of each other.

These was NO sonic difference in the pairs that I could detect.

Not sure about longevity, but SQ wise, a waste of money...

does nothing. just marketing fluff