Google and it's mastery of the internet and message boards is leading me to believe I might be able to run KT88 or 6550's in my SC120 after a rebias on the stock Partridge trannies. I want to ask: 1) Would that work? 2) Would it make a noticeable improvement in power? Those six EL34 walk all over 100w tube amps already. Ummm... that's it. I'm trying to decide whether to keep or sell this head right now and I'm leaning towards keep. If I can pull an extra 80w out of it way down the line it's definitely staying.