Pair RCA 12SL7 12SL7GT Vacuum Tubes Gray Bottle NOS NIB 6BW11 NOS NIB These two Hytron 7C4 tubes

These two Hytron 7C4 tubes tested to spec on our Paul Hart-calibrated TV7/U

One is an early 1X2

They are dead quiet when the CD player is paused and have excellent frequency response

They are dead quiet when the SACD player is muted but are not recommended for this amp -- which was designed for 6SN7s -- as they not only break up early

All of these tubes have very-good-testing triodes and each has a strong-testing as well as a functioning diode

Pair RCA 12SL7 12SL7GT Vacuum Tubes Gray Bottle NOS NIB 6BW11 NOS NIB These two Hytron 7C4 tubesThis new old stock, new in box (for Tube Two) aesthetically matched pair of gray glass RCA 12SL7GT dual triodes was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. Transconductance measured 36 36 for Tube One and 48 48 for Tube Two where minimum (65%) is 32 32. These tubes have gray coated bottles; black plates and bottom, D getters. Tube Two has a narrow crack in its base which, nonetheless,