I have only limited experience with the specific pieces of gear you have in your system: the Kubala cables, just barely left of dead neutral and superbly transparent. The Pass xa30.8 is an exceptional amp. Before you dump the PS Audio preamp, which Ive admittedly never seen or heard, you may wish to try some different tubes. Ive listened to alot of 12au7’s through the years and the Telefunkens are not among my favorites for tone or texture. Could I suggest you drop in some NOS Cifte’s/Mazda’s for a more illuminating presentation or NOS Mullard’s/Brimar’s for a more fullsome, tonally saturated presentation.
No offense intended but you have such a variety of gear there that I would venture to guess that no one can assist you more than to blind guess along with you. I must admit though that Ive never heard of anyone....you are the first....who drives a Pass Labs XA amp with a PS Audio preamp. I use Audio Research in my main system and when I had a Pass Labs XA amp I drove it with a Ref5se and it was a terrific combo.
Good luck.
No offense intended but you have such a variety of gear there that I would venture to guess that no one can assist you more than to blind guess along with you. I must admit though that Ive never heard of anyone....you are the first....who drives a Pass Labs XA amp with a PS Audio preamp. I use Audio Research in my main system and when I had a Pass Labs XA amp I drove it with a Ref5se and it was a terrific combo.
Good luck.