About KT66KT66 was introduced in 1938 in England. Electrically, it is very close to 6L6. This is not surprising, since original KT66 design was sold to RCA who turned it in to 6L6. KT66 has been used in high end audio amps in Europe, as well as legendary Marshall combo amps in the 1960-70s.
KT66 vs 6L6In general, KT66s tends to have a bit warmer sound with more low end. It is a good choice for those who are considering 6L6 upgrades. Please note that KT66 draws more heater current than 6L6. When in doubt, check with manufacturer or others who have used KT66 in 6L6 amps.
Excellent AudioKT66 was originally developed for HiFi audio. Notably, it was used triode-connected in low distortion Williamson topology amps from Leak, Quad and Heath. These amps have excellent sonic which are still highlly prized in classic Audiophile application. If you are considering 6L6 upgrade and your amp can handle filament currrent, KT66 is an excellent choice.
This is a Genalex Gold Lion KT66 re-issue made in Russia. This tube boasts the same form factor as Chinese or Groove Tubes KT66. Gold Lion KT66 is built to last with durable and high quality construction.
In guitar amps, the Gold Lion KT66 has the roar that's expected of KT66 tube types, but it carries it to bigger volume really well. On audio amps, KT66 Gold Lion is articulate and is a step above other KT66/6L6GC types in sound stage imaging.
Price is for a matched quad (4 tubes) of Genalex Gold Lion KT66
With heavy duty glass and solid construction JJ KT66 provides balanced tone with good amounts of midrange in guitar amplifier.
Price is for a matched pair (two tubes).
Price is for a matched quad (four tubes).
TungSol Re-Issue KT66 is built in Russia. It has extra large glass bottle for high power dissipation and full smooth tone.
Price is for a matched quad (4 tubes) of TungSol KT66 New Issue.
Chinese Genalex KT66 reissue. Excellent in guitar amps (described as Best Currently Produced by Rivera Amps), nice agressive tone in Marshalls. Very neutral and smooth voicing in Audio amps.
This tube is made by Shuguang, and is sold under different labels (Valve Art, Sino, etc.)
Price is for a matching quad of Chinese KT66.
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