Kt 88,
I ran those 6nc3's last night. My friends assesment of the 6l6 versus el34 is on the money. The 6nc3's are very musical. They are not the best at retrieving details (micro-dynamics) nor the lowest octaves and have a slight mid-bass boom. However, the way they present female vocals is awesome, similar to an el-34's presentation with syrup on top. I listened to Diana Krall, Cassandra Wilson and Lisa Ekdahl and was impressed. I'm going to run them for a little while, but plan on going back to my Golden Dragon kt-88's (they're more my cup of tea).