NOS VINTAGE Date Code Matched Pair 1960 Mullard Blackburn 12AX7 ECC83 I61Tubes

Tube Type / Number: 12AX7
Actual Brand*: Mullard
Printed Brand: Mullard
Quantity: 2 Pieces - Matched Pair
Matching Date Codes? Yes
Plate Construction:  Gray
Getter Construction: Top O
Country of Manufacture: Great Britain
Visible Date Codes: I61 B010
Lettering Condition: 100 Percent
Number of Mica Spacers: 2
Mica Spacer Shape: O
Glass Coating: None
Engraved Base? No
Boxes (always included): Generic White Boxes - These Came in a Military Bulk Pack
Notes: Date codes point to 1960 as the production year.

Testing & Matching: We have multiples of these in stock and therefore are not listing the test results here. All of these have been tested at real world voltage on a Maxi-Preamp tester for both Gain and Gm. We guarantee that these will test at or above NOS values. These are truly NOS tubes with no hours on them. Matched within 15% by Gain and Gm.

** Please note, many tubes will test NOS but will actually have a few hours of use on them. A truly NOS tube will have excellent getter flashing condition, no dirt/grime, usually in the original box, and no filament deposits. If a tube is listed  as "tests NOS" but is listed as "not True NOS" please expect the tube to have a small amount of use * 

All tubes have been tested using only the best tube testers. We have a large fleet of tube testers, and every single one of them has been calibrated within the last year by industry experts. We mainly use the Hickok TV-7D/U, but occasionally we may use a Hickok 539, 533A, or 600A.