I'm planning on making a ST-70 clone, based on Kara Chaffee's MKIII mod, like my MKIII + Akido. I was thinking of instead of a 12AT7, using a 12AX7/5751/6AV6/6AT6. What would I have to replace to use one?
I was looking at the DIYTube ST-70. It's very close, except for the LM334 and the capacitor (C2) between the 5751 and the 12BH7.