Owners of McIntosh MA 2275: need help with tubes

As implied in the above responses, replacing the small tubes will have a larger impact than replacing the KT88. You can go to audiokharma McIntosh forum and read about this till you get exhausted. Above recommendations are good, though.

I have a MA2275 and changed the chinese tubes. Used NOS Telefunken 12AX7 for V6 & V7, these are the preamp tubes, which when changed make a world of difference. The 12AT7 are the left & right channel driver tubes with NOS Telefunken and absolutely love it. I didn't change the V4 & V5 because these are the phono stage and I'm not using them right now. I bought tubes from Brent Jessee Recording Supply.

Telefunken,GE,RCA....12at7

I heard about it but never audition.
Go for Genalex KT-88 (copy)
12ax7 Telefunken (smooth plate).
You will get almost the same response...majority.
Btw,i am 7591 tubes and Telefunken 12ax7 on my pair of mc-225.