Like the 12AT7, with Gold contacts.
JJ Electronic KT77 Quartett
JJ/Tesla Hi Power- for e.g. Hughes & Kettner®, Engl®
JJ Electronic KT88 Quartett
JJ Electronic KT88JJ Sextett
JJ Electronic 6550 Sextett
JJ Electronic E34L Oktett
Preamp tube with a beautiful, warm sound
JJ presently produces 2 versions and haven’t yet decided which will be the final model: 1. Grey, spot welded anode metal sheet...
JJ/Tesla smaller pistons
Low noise preamp tube
Developed for operation with up to 500V in pentode circuits