Really enjoying this great amp. Sounds beautiful with the stock tubes but I have been rolling some nos tubes both in the Torii and through other components. Just an amazing amount of sound variations can be had with changes to phono stage, dac and preamp not to mention the 5 different sets on the amp.

Lots of good, realistic posts here on tube rolling which I appreciate. Have not found anyone who might have tried Sylvania 6CA7 big bottles in this amp. These tubes have me intrigued as this is the only stage I haven't tried nos. As these are scarce, and knowing that matching is not required in this amp, can anyone suggest just how far from nominal one can go with quads in the power stage. One dealer said 15% but it would depend on design (even with self biasing).

I will report on some of my findings and preferred combinations but the process takes time so it may be a while. The JJ 6CA7's do sound good (I have nothing else to compare) and I might not go nos with these. I agree with Lon and others that the stock OA3's are darn good! Just my opinion. Anyone have anything on matching?