Chad, I probably pointed you towared this question from my answer in another post. As I recall (and I do 'think' I'm correct because I was looking at pre-amps at that time already being a SF amps(s) owner. When the first model of the SFL One came out in the early 90's in a review in Stereophile as I recall said it had the option (by using an internal switch) to change between the 12Ax7 and 6922. Apparently in later editions this must have changed to just the 12AT7. I guess you sould just check your owners manual, a schematic, or pop the lid and check for yourself. Sorry if I caused any confusion.
