The 805 series has been in production for a number of years. While there are some internal changes in the 805C over the 805B, the biggest difference is the output tube. The B uses a 211 and the C a 845. They both use the same input and driver tubes. I had the 805B in my system for a number of years with NOS tubes, I auditioned the 805C in my system for 2 weeks and found the differences subtle at best and decided to stay with the B. Go to the Cary Audio website and look at the review section, there is more information there. Good luck.
