Mullard 12AX7/ECC83 Long Plate Vacuum Tube.
17mm Long Plate with copper plate posts.
Legendary (for a good reason) Dual Post (aka Goalpost) Getter support with large O Getter.
Made in England in 1958.
If you love the sound of short plate Mullard 12AX7's and haven't tried these, you will be amazed at how much better these will sound.
This design has f91 code and was in production from 1957 to early 1959.
Very similar sound to their immediate predecessor, square-getter mC1.
Many audiophiles like f91 than mC1 because of their fuller sound from low to mid range.
All of them test like NOS or very close to NOS and have f91 code.
All are tested great in my line preamplifier for noise/microphonics.
Matching pairs are available.
Upon request I will send you photos and detailed information including measurements and date code.
$120 for 1 tube.
Tubes are fully tested by precision calibrated Hickok 539C tube tester. No shorts, leakage or gas.
USPS Priority mail shipping with tracking within US will be $9.
Payment by check or money order (no Paypal please).
Local pickup with is welcome.