Matched Pair RCA 12SN7 12SN7GTA Vacuum Tubes Black Plate NOS NIB Tung-Sol 6K6 " "My Darling's Ring

" "My Darling's Ring

though they are labeled differently

They sound spacious with excellent dynamic range and frequency response on these challenging pieces -- and are dead quiet when the CD player is muted

engraved bases and narrow rectangular mica spacers

It rattles but is otherwise OK

Matched Pair RCA 12SN7 12SN7GTA Vacuum Tubes Black Plate NOS NIB Tung-Sol 6K6 " "My Darling's RingThis new old stock, new in box matched pair of RCA 12SN7GTA dual triodes was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. Tube One measured 76 76 and Tube Two measured 79 77 where minimum (65%) is 50 50. They have short bases; tall bottles; D getters; steel support rods; DB and CV batch codes, respectively, and their top mica spacers have two X patterns incised into them. I am playing them