Matched pair of old stock Mullard Great Britain Blackburn plant 12AX7/ECC83 tubes. Matching date codes of I61 B2I4. The I61 is one of the most desirable Mullard ECC83, being a very early short plate version that sounds fantastic. Really hard to find in this condition, On my calibrated Hickok 533A tester, these tested as new with no shorts at:
tube 1: 1275/1250
tube 2: 1250/1250
where 1250 is considered new.
As illustrated in the pics, these tubes have seen very little use. Mullard 12AX7 typically get very dark on their bases very quickly. These are almost completely clear! I had these as a backup pair, tried them out only for a few listening sessions to make sure they worked, and have had them on the shelf since. I no longer have a need for them after a big system change, and am passing on these beauties to someone else.
Buy with confidence from a long standing audiogon member, and feel free to ask questions. Thanks for looking!