Question for tube aficionados

I have a Unison hybrid integrated which uses 2 12au7s in preamp end.  I have used two different Mullard 12au7s, RCA Cleartops, and Radiotechnique, but the Siemens 12au7 NOS (got mine from Upscale) beat them all.  Beautiful full bottom end, great midrange, and an open and fantastic top end, no brightness but crystal clear.  Wonderfully dynamic.

rvpiano, Check with CJ, but FWIW I can't think of a single reason why tube selection in the line stage would affect the performance of the tubes in the phono stage, except for the obvious one is that the phono stage signal passes thru the line stage therefor any tonal changes brought about by the line stage tubes will be reflected in the sound from the phono (or any other) source.

Hello Rvpiano, I had no intention on visiting this forum again but I’m on a email list that generates recent and past discussions and I browse the list for interesting topics. 
So to answer your latest question, I believe that the unit can play it’s phono section without tubes in the line stage- but I also believe that when tubes are in the line stage, it may affect the sound of the phonostage slightly. 
When I used my PV-11 as my main preamp, I chose to use the purest and most revealing digital / cable front-end but for for my phonostage, it was very different, I chose a very musical cartridge. This was how I balanced both sections of the PV-11 to sound close and very good.  I still do not understand why CJ would make preamps where one stage would sound so superior to the other.  This is not the only preamp they have done like this.  I believe CJ really believed at the time that digital sources were all analytical and hard sounding. As I mentioned before, my main preamp now is the Audio Research SP-11 Mk2 and it has a wonderful phonostage that is definitely on par with its line stage but I actually prefer the sound of the phonostages from CJ tube preamps.  I have my system setup to use the line stage of the AR but my vinyl is played via the phono section of my CJ PV9a.  Rvpiano, if you check eBay, you’ll see 7316 tubes labeled all different names, but you want the ones made by Amperex and it does not matter if the getter is round or D shaped, they sound identical. Good luck enjoying your PV-11 and try balancing your system as I did when I had my PV-11 as the main pre. If you ever think about upgrading, don’t do what I did and sell the PV-11. It took me years before I got mine back.  Keep it because many of Conrad Johnson preamps made in the 1980’s have killer phonostages. My favorites CJ phono sections are the, CJ Premier Three, PV-5, PV-8, PV9a, PV-10a and PV-11.  All of these have their own special tube magic.  

lowtubes,

It certainly is true that the phono stage of the PV11 is wonderful.
 I’ve placed a bid for a pair of Amperex 7316 tubes on eBay.
Meanwhile, I’m sampling NOS Telefunken AU7 tubes.
Amazingly, these tubes have brought the sound of the line stage very close to the phono stage. If I win the bid for the Amperex, I’ll compare them to the Telefunken.

Rvpiano,
I’m not surprised that you notice such a significant improvement in the sound quality. The point numerous posters have made on this thread is true, better quality tubes are unquestionably impactful. Congratulations. I didn’t understand the comments of some who suggest that there wouldn’t be much of a difference. Average quality tubes will only restrict/limit the true potential of your preamplifier. The basic design and circuit of the PV 11 is good, but held back by mediocre tubes in the line section. 
Charles