I've heard putting a set of THD Yellowjackets in the pre section of my Dual Rect will make it operate like a class A, is this true? And do I have to mod anything when swapping? 8)
Yes. I've had YJ's in my Dual Recto for almost 4 years now, and they'll be there for a very long time. I run them in conjunction with EL-34's. As far as I'm concerned, they do high gain extremely well.