Matched Pair General Electric GE 12B4 12B4A Vacuum Tubes Valves NOS NIB Sonotone NOS NIB They measured 62 and 76

They measured 62 and 76 where minimum (65%) is 46 and 100% is 71

new in box US-made 6F7 tubes tested to spec on our Paul Hart-calibrated TV7/U

This Telefunken ECH81 / 6AJ6 was tested on our Paul Hart-calibrated TV7 for shorts

It sounds terrific and has great bass and sparkling highs and Donald Fagan’s voice is warm and clear as a bell

1941 in fulfillment of a US government contract for which WE had insufficient capacity and had to subcontract out

Matched Pair General Electric GE 12B4 12B4A Vacuum Tubes Valves NOS NIB Sonotone NOS NIB They measured 62 and 76This new old stock, new in box matched trio of GE MANUFACTURED 12B4A tubes was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. They measured 47 and 50, respectively, where minimum (65%) is 32 and 100% is 49. Wish I could tell you how they sound, but I don't have any equipment that uses these. WE HAVE SCORES OF THOUSANDS OF VACUUM TUBES. IF IT'S NOT LISTED, WE MAY HAVE IT. PLEASE ALSO SEE OUT