KT150's in Rogue Cronus Magnum ii

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.

Twoleftears what small signal tubes have you tried?

How long did it take to break in the rogue?