I just bought a new Cayin 688R on sale, a KT-88 tube integrated amp. I'm wondering if anyone has had a chance to compare and contrast the sound quality of the following power tubes (it will use two 6N6s and four 12AX7s in the preamp section):
a) GE NOS 6550
b) EAT KT-88
c) Grant Fidelity Sh. Treasure KT-88
In terms of modern tubes, I'm not much of a fan of the Winged C 6550 sound (great detail but a bit on the dry side), but don't enjoy the too-warm effect either (Golden Lions, etc.). I'd like to find something right down the middle - accurate with a reasonable degree of tube warmth and dimension.
If anyone has a suggestion I'd greatly appreciate it. This is the amp: