Power Tube Break-In Procedure


I just purchased a set of Sophia 300B 2.5v Princess tubes from Sophia Electric. They recommended allowing the tubes to cool off for at least 30 minutes after running them for a maximum of four hours. I think they meant just during break-in, but not sure. They claim that this can dramatically extend the life of the tubes. Has anyone heard of this? Why would this extend tube life?
smeyers
>>The big thing is not to turn the gear on and off multiple times in a day....I switch my tube amp on in the morning weekends and turn it off at night when I go to bed.<<

Yes, that's what I figured. But the folks at Sophia told me to not keep the tube on for too long during break-in. They seem to feel that the heat during break-in can shorten tube life. This is the question that I'm wondering about, that is if anyone else has heard this before.
>>Sounds like mind games!! If you believe something, does that make it true?<<

Huh??
The big thing is not to turn the gear on and off multiple times in a day....I switch my tube amp on in the morning weekends and turn it off at night when I go to bed.I'm using TJ Full Music tubes which makes them for Sophia also.
Larry