I just bought a JCM900 50Watt 2 12 combo off ebay. It works great, but I was wondering how it would sound if I swapped the G12T 75Watt Celestions with the set of G12M 25 Watt Green Backs I have? If I wired the two 25 watt 8 ohm'ers in series they would handle 50 watts at 16 Ohms.
And have any of you mucked about with swapping tubes in a JCM900? Would you? Why?

Mike