Amperex PQ 6922 vs Amperex PQ 7308


I've read the Joe's Tube Lore re: 6922.There was NO mention of PQ 7308.Will these still be the same performers,or is one superior to the other.Thanks!!
sirspeedy70680e509
There was also a military version of the 7308, no shield or PQ.

That said, if anyone is in need of some white or orange label Amperex 7308 PQ USA made I have a couple pairs I could part with. Also a single D-getter white label holland tube.

I've compared to a bunch of 6DJ8s (which are nice, and a lot more common), both are good but I'd rate the 7308 a fair bit higher.

-Ed
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TVAD. Joe's mention of the description "shield" might refer to the "PQ" logo. It's a shield with the letters PQ and two stars inside. OR, he could be refering to the internal construction of the tube whether it's shielded or not shielded.

I have some 7308 PQ with the shield logo as well as JAN 7308 with no PQ logo. They are the same tube. PQ's were labeled for general consumers where JAN labels for the military.

The difference between the 6922 and 7308 is minuscule, to my ears.
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IMNSHO PQ=shield, it's the graphic that is on the tube. Sorry if I wasnt' clear. I have only had PQ with shield logo, not any that are either/or.

generally 7308s are quieter and better matched. they are selected 6922s, essentially.

the consumer versions pre-date the military versions in general. Age is by color of printing to a degree. white, orange, green for printing colors, oldest to newest. usually they have date codes on them too.

as with most tubes earlier=better.

-Ed