Anybody tried KT120 tubes on Conrad Johnson amps?

Great question John and I don't want to hijack this tread but I would very interested in any ones opinion of the TS KT120's and in which amp (mainly because it is such a new tube and I am also considering them).

Well I service C/J as well as ARC and it's funny you mention it because I asked them about KT-120's last week. Their answer was..."We do not plan on using that tube". So there you go. Because of the increased heater current when using the KT-120 it's possible they would not be compatible. I'm just speculating as they did not give me a reason.

This does not directly answer your question, but when I owned a Premier 11A the previous owner had been using KT-88s. He thought that they sounded great but wondered why he kept blowing fuses and why the tubes needed frequent biasing and replacing so often. Although it metered OK, the amp sounded so bad I thought that it might be defective. On a whim I ordered a quad of EH 6550s and after replacing the KT-88s the amp sounded wonderful and no more blown fuses.

I used to have a Japanese customer, a very old school and old money guy who was raised very traditionally. When we would go out for sushi he would shudder every time I would add wasabe to my soy. He would admonish me "if the Itamae (sushi chef) wanted you to have more wasabi, he would have added it to the sushi!"

Long story short - I don't think that it pays to try and second guess the designers of the amp.