KT150's in Rogue Cronus Magnum ii

I would contact Rogue and listen to them instead of advice from an audio forum.

I would contact Rogue and listen to them instead of advice from an audio forum.

But a number of us forum members have already talked to Rogue specifically about KT150. They’re a small company, so it’s nice to share information amongst owners rather than consuming more of their amp-building time for simply-answered calls and emails (though they are extremely pleasant to talk to in person).

KT150 is not recommended for any of their amps. I asked Rogue about using this tube in my Apollo monoblocks, since going from KT90 to KT120 was such a nice upgrade (one that Rogue themselves readily adopted) -- the answer was no; at a minimum the transformers would need to be redesigned for the KT150. Don’t do it. Would’ve cost me ~$1200 to re-tube, anyways!

When I had my CM2, Rogue told me the same thing, not to upgrade to KT150.

Thank you everyone for your input.

This is rather OT, but I recently dropped in some Genalex Gold Lion KT88s, and when I get round to it I'll be going back to the Tung-Sol KT120s.  Not a night a day difference, to my ears.  88s perhaps a little more liquid/forgiving, but lost some of the, well, majesty that the 120s gave to full-scale orchestral.  If you have the 120s, I'd be content, and just play around with the small signal tubes.