Western Electric 300b Tubes - Differences

The expensive variety come in sealed boxes, with individual serial numbers for each tube, testing results pamphlets for each tube, all packaged inside an engraved (reads Western Electric, etc.), cherrywood case. They come with a 90-day warranty that becomes 5 years when you register the warranty cards.

The uber-expensive type ($1500/pr+) were packaged this way AND were produced in decades past.

Those you list as cheap, I've never seen them in that type of packaging. You could ask Westrex Corp., but if they do not have individual serial numbers, extendable warranty, etc., I'd be suspect.

I've done a little research on this. Western Electric makes OEM tubes which come in a blue and white box. These are sold to manufacturers of amps which use the 300B's. The specs are the same but they don't come with a warranty. I don't think these are suspect. I'm still trying to get the final word on them.

AFAIK, what Bander says is exactly the case. Major problem is that most of the OEM tubes are not sold as matched pairs. But if your amp biases the tubes independently, that may not be much of a problem.