What tubes does the F2B use and where can I get replacements?
Howierd

Howierd; I believe the quick answer to your question is two 12AX7's.  These are apparently also known as 7025's and ECC83's.  A starting point for looking might be here.  I don't yet have an F-2B and I've never been inside my F-1X; but from the discussion above, you might need to consider the physical size of the tube before ordering.

Dave,
I've had my F2B for 26 yrs and it's never failed. So I guess I'd better get some spares just in case. I have heard stories about people buying tubes just to find out that they are too big or don't line up right. Thanks for the link.
Howierd

Sorry came on to this thread late. To the person using SWRs: If you want to reduce your amp idle hiss, and you are not opposed to swapping tubes, swap the ICs in your SWRs which are probably TL072; and use a NE5534 or better. Your amp idle running hiss will be history.