This may be more of a rant but this has me so dissapointed. I purchase about a dozen power tubes a year and, while this is anecdotal evidence, I don't believe it's entirely coincidental that nearly HALF of all new power tubes - factory matched and tested, reseller matched and tested - have mechanical noises, as in loose rattling components inside of the tube - which about 2/3 of the time translates into a microphonic rattle. Now - I know good NOS tubes - but for amps going out the door I'm constantly stuck with rattling tubes - my supplier makes good on them but often the replacements have the same issue. In the end I end up with a bunch of tubes I can't use. I don't expect the factory to check for mechincal noise - they clearly send any tube out the door that "functions". So they aren't going to help us. Is there a reseller (even if they charge $3 more per tube) that simply holds a tube up to their ear, gives it a shake, and if they hear a rattle, trash it? I'm just at a loss - I've experienced this with JJ a lot (as I use them most as I like their 6L6 tone) and TAD as well, but never with the Sovtek/EH (so I am going to try and go with them more). But seriously - are there resellers actively testing power tubes for microphonics and actually burning in tubes for 24 hours before matching (to weed out bad tubes and help them keep their bias numbers more?) And I mean a reseller who I NEVER have to call up and ask for more tubes and box the old ones back up or even keep them (when they are trash). Obviously the way to turn a profit on tubes is just to hope no one complains and send them all out. But I have new power tubes with three dang silicon rings on them that still rattle and life is too short to be dealing with rattling noises. Anyone with me here? If some of you have no idea what I'm talking about, where are you getting your tubes?