To my ears there is something about the 9 FRONT end that really works, and I can not duplicate that tone with anything I have found on the 12.
This is just a pure gut feeling but I believe there's tone in power. Or more specifically, in headroom.
Let's say you have a 600 watt head and a 900 watt played thru the same cabinet at the same volume. While both might be able to hit the same volume, one is working harder than the other.
Actually, between 600 and 900 watts there won't be that big a difference in perceived volume. But while the 600 might be straining to reach that level, the 900 would just be cruising.
(And all the above is based on the preamps having similar output to the power amp.)
I had good tone when playing amps (from different manufactures) in the 300 to 500 watt range. I have great tone now playing amps (from different manufactures) in the 900 watt range.



