Has anyone had problems running kt-120s tubes in there power amp?

jake-

Did they tell you what kind of problems some were experiencing?
I've been running KT120s in my Rogue M-180 monos and find they run so much cooler than the KT88s did in my Cary CAD-120S Mkii which ran quite warm. I'm not knowledgeable enough to know if that's due to tube design or amp architecture, just relating my experience of never having a problem with the KT-120s. I asked Cary about putting KT-120s in the CAD120S Mkii and was told it would be a great match, but I never did since shortly after I moved over to the Rogues. Since the folks at Cary have also told you it would be okay, my advice would be to put them in, do some listening and see what you think.

Jerry

AR doesn't recommend kt120 tubes for use in their Kt88/6550 amps and you wonder why people who ignore AR are having problems. Cary says it's okay to use KT120 and I have not read any reported Cary problems. I don't see your delemia 

My friends with audio research amps said it was lamicods on the transformers and breaking them down which ended up having to replace the whole transformers of there amps. Because of the demand on the kt-120 tubes was to hard on the transformers. Also my Cary Cad 120s is my biggest and most beloved audio purchase and i runs hot enough as is. I got it when the Canadian dollar was at par with the US dollar and never had an issue with it. And i plan on keeping it for over 30years. So I want to take the best care of it so i never afford to replace it now. Thats all

Two different amps and apparently your manufacturer told you you can use them. Did you try them or simply put them aside because they don't work in AR amps?

Hello again, I just answered you on the Marantz SA-11S3. I've been using the KT-120 tubes (12) in my older Rogue Zuess amp with great results. Tremendous increase in blissful easy power. Night and day difference to the KT-88 tubes.

I don’t recall anyone with ARC amps having actual issues with 120s, or at least issues that were reported here, although there was a lot of speculation and trepidation. I began a thoroughly scientific and utterly informal and perhaps meaningless survey that determined that nobody reported actual transformer issues from 120s. I ran 120s in my Jolida 502P for a couple of years and they worked perfectly until simply wearing out…150s seemed a little much for the amp but 120s…no problemo. I use Gold Lion KT 88s now because I like them…they’re pretty...