Cryo treated tubes?

[Mick Bailey]

A few months back I did a repair on an amp and it needed a set of tubes. I ordered some Sovtek 5881s 'premium matched' and the guy turned up unexpectedly with a branded set of the same tubes that he'd bought himself, Cryo treated. I did an A-B on them and couldn't tell any difference. The trouble is by the time the amp has cooled down, the different tubes fitted and re-biased, my sound-memory fades. One A-B test can't provide a valid evaluation. You'd need to derive a meaningful sample size and repeatable, objective test to be more accurate in order to establish that the results would be representative of the wider population.

The factors to consider are the same as any other survey for cat food, shampoo etc., The sample size, percentage and population size. Then you can derive the confidence interval and confidence factor. Then the results can only be meaningful if the test set is truly randomised.

I doubt whether any supplier of cryo tubes has done a proper statistical consumer test. Personally, my gut feeling is that it's BS, but who knows?

Maybe tubes that have been hit with a Bible sound better than ones that haven't.

[Leo_Gnardo]

Sounds a bit like that famous Glasgow delicacy the deep fried Mars bar and I wouldn't eat one of those either.

Deep fried Mars bar, mmm. What else would you have for dessert after finishing off a nice big plate of haggis?