4 Vintage Genalex KT77 Gold Lion Power Tubes, Made in England, 1960s Master Box, All Test Strong with Postive Life test, Ex Sound, Superb, The Best 1960s | Reverb
EL34 vs KT77 Tubes - What is the Difference? - Humbucker Soup
Biasing the Genalex GL KT77 to get the best sound - Talkin' Tubes - The Klipsch Audio Community
KT77 Gold Lion brown base NOS with faded Gold Lion logo (7848=1978) (95ma) (tested on Amplitrex)
Tube Amp Doctor KT88 Redbase Premium Matched – Audiotubetech
KT77 VS EL34: Which One Should I Choose? – Upgrade Home Devices