Amperex PQ 6922 vs Amperex PQ 7308

Amperex made a "regular" and a PQ version of the 7308 tube. I have a pair of each. The PQ version seems a little more extended at the frequency extremes, whereas the regular versions are more "midrangey"/"tubey".

Hope that helps.

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

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.