I'm building a second Crack. The first one is a very tidy stock build. Sounds great. It's my benchmark/reference. Second Crack is going to judiciously hot-rodded. I like the 12AU7. I lived a very long time with this tube in a Conrad-Johnson preamp I really liked. But for the second Crack I would like to try a different tube in place of the 12AU7 - the 6CG7, which is also a tube I know well and like well from long Conrad-Johnson amplifier ownership. ...and the same story again for the 6SN7. I would prefer to wire the new Crack with the noval socket.
I have zillions of nice 6CG7s/6FQ7s, and also many nice 6SN7s. I know that the 6SN7 and 6CG7 are electrically identical - same tube in octal and noval miniature packages - but people make claims of a fair sonic different between the two. Even though I've used both tubes, I've never used them in the same equipment to be able to compare more directly. So, I would like to be able to try the 6SN7s, too, and I'm considering a 6CG7 noval -> 6SN7 octal adapter.
Any opinions on using adapters? I read many people use them, and a few have had some problems, most folks haven't.
Thanks.