KT66 vs KT90

Yes it can. The only concern from Rogue was the heat of one the tubes being too close to the electrolytics. Otherwise Mark love the KT120. I should get a set and clear out some space for airflow and give it a try. Thanks. I probably wouldn't want KT66s now, knowing that they output less power.

Cool! Yes, the KT-120s DO generate more heat, and heat is not a friend of electronics. You may want to buy a fan to keep the amp's "innards" cool. And, be sure there is plenty of air flow too. If you try the KT-120s, please report back with your impressions. The tubes need at least 25++ hours to break in. Make sure bias is set properly.

Dhcod...if you try the KT-120s make sure you check again with Rogue Audio what they recommend for bias setting on the new tubes.