Gthirteen. I suggest you call Antique electronics or whoever your favorite supplier is, and order Amperex 7316 tubes to try in place of the 12AU7. The Amperex is lively, quiet and has excellent tonal balance. If you find it is not warm enough, then try the Telefunken 12AU7. Neither of these will do any harm to your CJ.
Conrad Johnson PV11 tube noise
After about 2 hours of being on, my preamp will occasionally give a sustained "chirp" or sometimes a longer high pitched ringing sound, pretty basic tube noise. I typically listen at low to moderate levels, and it is therefore often audible during listening. What can I do? CJ says to use the tubes they supply, because it was designed around them, Upscale Audio says that the PV 11 is a pain with regard to retubng, and He wasnt in a hurry to sell me ANYTHING because of this. It simply cant be that this type of noise is just what you have to deal with when you want to use a tubed pre. What do you think I should do?? Has anyone used a PV 11 successfully with NOS or other non-CJ supplied tubes?? Thanks.