Hey, Doug - good morning! Here`s peace and quiet a little...maybe some of our "most popular" themes is needed :-). Not that it`s incredible hard, there`s some "step by step" sources for doing it, but I`m just too lazy. I like when "most of the action" is happening in class A, anyway... Then just analize one half like ordinary SE amp working in Ra, and our Raa = 2*Ra... It work, good enough for me...