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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
Post removed 
hiwaves
43 posts
 
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.
cosmic_void
142 posts
 
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.
clueless
763 posts
 
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,
jeffloistarca
1,004 posts
 
If tubes are anything like semiconductors (which I have 20 years experience with) the "differences" have to do with testing and traceability. Military semiconductors come off the same line as the standard devices do, but are subjected to a specified barrage of tests. Commonly referred to as "shake and bake" the military testing weeds out devices that may fail early on. The other significant difference is the paperwork that follows military devices through the factory and test floor, keeping a log of the measured specs as the part goes through the cycle. The parts that pass the military testing are sold under different part numbers and sell for a considerable mark up, anywhere from 10x to 40x the standard device pricing. Just to make things more confusing there are several levels of military screening: 883C, JAN 38510, and Level S (space level, for aircraft and space applications).
Bottom line is they come from the same production line as the chip sitting in your coffeemaker but are tested to insure longevity and consistent quality. Is it worth the premium? They are more rugged so they will last longer, other than that, no.
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