Matched Pair Sylvania 6BL7 6BL7GTA Vacuum Tubes Triple 3 Mica NOS NIB Music Of The I am playing it in

I am playing it in my Pro-Ject Tube Box S phono preamplifier with an Ortofon X5-MC high output moving coil cartridge as I write and it absolutely silent

new in box GE 5 Star 5663 premium tube tested to spec on our Paul Hart-calibrated TV7/U

side harp getters

Tube One measured 60/56 while Tube Two measured 61/58 where minimum (65%) is 50/50 and 100% is 77/77

I have played it in my Bottlehead Crack headphone amp and it sounds great

Matched Pair Sylvania 6BL7 6BL7GTA Vacuum Tubes Triple 3 Mica NOS NIB Music Of The I am playing it inThis new old stock, new in box, almost perfectly matched pair of Sylvania MANUFACTURED 6BL7GTA dual triodes was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. Transconductance measured 46 48 for Tube One and 48 47 for Tube Two (Sylvania MANUFACTURED, RCA LABELED). (Minimum (65%) is 25.) They have top D getters; anode radiators for cooler operation and longer tube life; copper support rods; a