Valvo 12AT7 ECC81 Vacuum Tube For Your Univalve Zenith 7476 7678 They are dead quiet when

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

Sold as-is until I find a setting

I have listened to this entire album and It has light to lightly-moderate surface noise audible in quiet passages and barely-audible in voice-level passages

These tubes have lyre-shaped getters

These tubes all have small logos as well as 048

Valvo 12AT7 ECC81 Vacuum Tube For Your Univalve Zenith 7476 7678 They are dead quiet whenThis Valvo 12AT7 ECC81 dual triode was tested on our Paul Hart calibrated TV7 U for shorts, gas and transconductance. There were no shorts or gas. Transconductance measured an underwhelming but well balanced 40 42 where minimum (65%) is 50 50 and 100% is 77 77. This tube has nice silkscreening; a flared base; sutured tops and excellent flashing. It sounded great in my Bottlehead, though is not recommended for this headphone amp which was designed for