Tube myths Joint Army Navy vs Non Joint Army Navy


Joint Army Navy tubes, commonly referred to as JAN tubes, were tubes produced for the military. Tubes meant for the military, had to meet certain specs, as outlined, in the contracts, each manufacturer, had with the military. Though some contracts, called for a specially produced tube(RCA 5692, for instance), the vast majority of them, called for the same specs, as the industries, who tubes were mainly produced for, had. Consumer use, of tubes for audio, was small in comparison. The reason most think JAN tubes, are "better" tubes, is based on the myth, that they are different tubes. If the specs on a tube, say 6922 for example, were the same, for the Navy, as they were for , say, Hewlett Packard, then both tubes, were ran off the same lines(at different times, as orders dictated), with the same tooling, and same personnel. They are essentially, the same tubes. Most factories, ran a certain number of tubes, and then labelled them, as the orders, dictated. So a tube labelled H/P, was the same as a tube labelled Beckman. So you tell me, "which tube is better?"
fletchj
said above by Fletch >>>"But it only takes to look at a tube, and see the same internal construction, to know that there are no differences>"

Can you really do this????

If you can just look at a tube and do a visual inspection and see there is no difference then why go to the trouble of an electronic tube tester and matching?

There can be small differences in tubes of the same type and even the same run. This is just part of what they are and the tolerances involved and the production process. My understanding is that some tubes used in some critical military applications (Mig fighters etc...) were subject to much higher testing and Q control. I was also told that one reason that some old tubes are so good is that they threw so many away in the QC testing. Making tubes was apparently a process where a good portion of the runs went straight into the bins. This makes a certain amount of sense.

To the extent it is true I cannot say.

It may also be true that for some/many audio applications it may not make a big difference.

Sincerely
I remain,
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Bought a pair of tube amps from circa 1955. The owner had JAN tubes recently installed. The amps sounded OK, but when i replaced the tubes with Amperex tubes, the amps sound incredible, they just SING !!!

So much for the "sound quality" of JAN tubes.
I can't understand why in this day and age there isn't a manufacturer of new tubes that can manufacture tubes that the audiophile community would want. With the ridiculous amounts of money we are willing to spend to get every last note out of our systems you think it would be a gold mine for some manufacturer.
said above by Hiwaves>>> "The owner had JAN tubes recently installed. The amps sounded OK, but when i replaced the tubes with Amperex tubes, the amps sound incredible, they just SING !!!
So much for the "sound quality" of JAN tubes."

I don't know what the sound quality of JAN tubes is, or if there is one such thing, but I do not agree that you can reach that conclusion from listening to one set of tubes in one circuit.

Sincerely
I remain,