Vacuum Tube Snake Oil Salesmen

clarifying my earlier post, 

@psvaneaudio has been busted sending out fake test results with their top tier tubes enough to make it like that they just arent testing them. 

theyve been selling dud horizon tubes for a good while. at one time the return rate was bad enough that their exclusive retailer,  amazon, posted a "frequently returned item" warning on some of the @psvaneaudio listings. 

ive seen on several forums customers bring this to their attention, as how theyre testing these and receive bot-style non-answers in stead of a legitimate response. ive written @psvaneaudio about this and gotten a nonsense response. 

Apples to apples only if the seller uses the same tester as the consumer.

@audition__audio 

That’s sort of true in the absolute sense; but relatively speaking, matching tubes should match when measured against one another.

The thing to ask yourself is if you would pay much more for tubes which were matched using numerous operating points from a vendor willing to spend the time and money to do it correctly.

Most, I think, would not.

Interesting. So, you already paid much more for tubes which were supposed to be matched but were not, now the question is would you pay much more than that for tubes which were actually matched?

I'm sure if you measured the transistors in an amplifier you would find deviations in those as well.

@invalid 

For sure, matching transistors can be critical. For instance, some amps don't let you adjust DC offset, they rely on a matching differential pair instead.

The advantage with transistors is that new ones from the same batch are most likely very close to each other already, and a majority of transistors are cheap enough that you can buy a dozen and hand-match them to get the best-matched pair possible.

Wow.

The OP wrote

”Very funny answers. But imagine a young person maybe not too experienced with things smashing the tube and having glass fly up and hit them in the face or what if I am in a wheel chair or vision impaired?”

They are in a wheelchair, or blind. That doesn’t make them stupid or incompetent.

Is it really that big a challenge for you to break a tube? Seriously?

Psvane tubes are manufactured in the same factories as Sino and Shuguang which have had a well-known dubious reputation for consistency. Theres that but tube vendors generally buy in lots, do a 24-hour burn-in to screen out early failures before stocking them and then add on noise testing and matching services at customer's request when ordering. I assume the initial failures are returned to the supplier, crashed down and discarded or sold to a less scrupulous dealers to be rescreened etc., and sold to less discriminating consumers. I would say selecting tubes from vendors like the Tube Store, Viva Tubes or The Tube Depot and the like who bet on their reputation to stay in business is a mark of good consumerism.

@calieng It seems to me that if you couldn't figure out a way to safely smash a tube without getting glass shards all over the place you probably can't test one correctly either.