6922 Amperex PQ White label... D or O-getter? Holland or Hicksville?

I have a pair of these:   https://www.audiogon.com/listings/tubes-amperex-7308-usn-cep-pq-matched-pair-test-nos-made-in-usa-gold-pin-2014-02-15-accessories-92821-brea-ca, from 1962 and '63(still identical construction), that are just sitting in a drawer.     You’re welcome to try them, no strings.    Just sanitize and UPS them back, after listening/auditioning.     PM me, if interested.

Wow @rodman99999 , that's the good stuff. These are mil spec matched with tight tolerances.

They do perform beautifully.    Just a little too warm, for my tastes.     To me; the grey shield, early '60's, Siemens CCa, is joy in my BAT VK-D5.

Is the "deep low end of the 7308" an actual phenomenon or merely the perceived effect of less midrange emphasis?

@pmboyd , there is no diminished midrange in these tubes. It's the wonderful liquid mids of an Amperex tube.
The 7308 presents a more powerful, deep low-end than  the 6922/E88CC.
Don't get me wrong, all the PQ tubes have great sonics. Much more realistic and smoother and without the the grain of the Bugle Boys.