Very early pair of telefunken ECC83 12AX7 diamond bottom tubes with beautiful original labels.
This pair was removed together from seldom used recording electronics manufactured about 1953.
Has matching print codes of eg and the very early Made in West Germany printing.
These would predate any of the first Amperex/Philips or Mullard long plate ECC83's I've seen and are incredible sounding with amazing detail, holographic soundstaging and just gobs of air.
Tested on a calibrated Hickok 539C tester at 1200/1250 & 1250/1300 where 875 is the minimum for good.
Thanks for viewing.