Rrog, what source are the complaints from ? I have not heard of such complaints.
My opinion is the tubes should be ran through several tests prior to cryogenic treatment. A poorly constructed tube will fail whether it is cryoed or not. A microphonic tube will still be microphonic, possibly slightly less.
I've sent a few things in for cryogenic treatment. The slight improvement is sometimes not worth the hassle and expense. The best bet, as many cable makers do, is treat the conductors first before making the cable. This seems like a real hassle to me, because how are you going to get the insulation back on ?
Another thing is any moisture in the air of the cryogenic chamber, will condense, making things wet, then the liquid on the parts will freeze. I believe this is why some parts look "old" after treatment. So the chamber should be de-humidified before taking the temperature down (or more correctly, removing the heat).
This would apply only on the outside of a vacuum tube.
So my advise is; if you really want to try it, start with some good sounding tubes, and preferably have an extra set to compare to (see how expensive this gets?). And if you buy them already cryoed, make sure there is a return period. Try them right away and make sure there is nothing at all wrong with the tubes; no funny noises, no ringing, etc.
Best of luck to you.
My opinion is the tubes should be ran through several tests prior to cryogenic treatment. A poorly constructed tube will fail whether it is cryoed or not. A microphonic tube will still be microphonic, possibly slightly less.
I've sent a few things in for cryogenic treatment. The slight improvement is sometimes not worth the hassle and expense. The best bet, as many cable makers do, is treat the conductors first before making the cable. This seems like a real hassle to me, because how are you going to get the insulation back on ?
Another thing is any moisture in the air of the cryogenic chamber, will condense, making things wet, then the liquid on the parts will freeze. I believe this is why some parts look "old" after treatment. So the chamber should be de-humidified before taking the temperature down (or more correctly, removing the heat).
This would apply only on the outside of a vacuum tube.
So my advise is; if you really want to try it, start with some good sounding tubes, and preferably have an extra set to compare to (see how expensive this gets?). And if you buy them already cryoed, make sure there is a return period. Try them right away and make sure there is nothing at all wrong with the tubes; no funny noises, no ringing, etc.
Best of luck to you.