New tubes in Rogue M-180 Monoblocks

I can say that my experience with KT-90s was not good , either. They didn't last long at all and when one blew it took out a resistor, burned a wire, and a fuse, in the amp I was using- not a Rogue. It was enough to keep me away from them more or less permanently. I am curious about the KT-120 and will ask Jadis if I can use it in the DA-60. I have a feeling they won't endorse it.The trannys on a DA 60 are big and probably could manage it but repairs on an older Jadis are Tre Expensive.

"08-29-12: Tobes

That seems like very poor longevity/reliability from the KT90 tubes - unless you're running the amps 24/7?"

The amps do get heavy use from morning until evening every day. But I also forgot to mention that the KT-90s were biased at 40 mA as per the manual. When I called Rogue to ask about the KT-120s, they said that their new recommendation was 35 mA, and that's what I've had the KT-120s at since I installed them.

I no longer have a full complement of KT-90s, so I can't do a re-evaluation of them. But I've never felt dissatisfied with the KT-120s.

I have been using the KT-120 tubes in the Rogue M-180 for about 6 months now. They replaced Genelex Golden Lion KT-88 reissue tubes. In my opinion they sound better than the 88's on every level and I have not noticed any drop off in performance to date. I talked to Mark Obrien before I bought them and he thought they made the M-180 perform its best. Most of what I have read FWIW about the KT-90 is that they were a little thin sounding, but i have nop ersonal experience.

Daverz,

Are you sure about the biasing? I was told by both Mark and Nick at Rogue the KT-120 should be biased at 40 mA, just like the KT-90. Are we talking the M-180 monoblocks or the Cronus integrated amp? The Cronus is to be biased at 35 mA, but the M-180 at 40 mA.

Actusreus, I don't remember who I talked to at Rogue. Maybe he thought I was asking about a Cronus. I'll try calling them on Tuesday to get some clarification.