Has anyone run KT66 tubes in their Germino Club 40 ? I have read that it is possible to do but have not read (or heard any demos) any comments about anyone doing it and how it sounded. Does anyone know if this can really be done safely ? I imagine the amp needs then to be re-biased. Wondering how the tone, response of the Club 40 is with KT66 compared with a JTM45 .