Question for tube aficionados

If you plan to live over a year or two, wise to keep both .
Their value will not decrease .

One never knows..........

I’ve owned the PV-11 for over 20yrs now. It was my main preamp for 10yrs but I have moved onto a AR SP-11 Mk 2. I still have the PV-11 in my collection of preamps. The tubes that sounded the best to me in the PV-11’s linestage is the Amperex 7316. I think other Bugle Boy 12AU7’s may sound good also but the 7316’s were the most musical and revealing tube for me.

I tried a lot of tubes in the PV-11 line stage and the 7316 will be the tube that will give you most satisfaction. It’s because it is very revealing but smooth and musical too. If you desire a more analytical sound, RCA clear top.   Mullard Old Logo 1960’s 12au7’s are my 2nd favorite along with the French made Cifte 12au7’s.

@rvpiano, a couple of questions;
Have you given the Amperex enough time to burn-in? Run them for 40 or 50 hours and then evaluate them.
Do you know if these are 1950s issue and what is branded on the label?
   The 7316's should present a 3D image with a sweet midrange. I agree with you that "Telefunken has a more refined and perhaps, clearer sonic picture."
But, as others have stated above, I find the premium, low-noise Amperex more musical. I'm not discounting your findings in any way, but I wonder if they need more run-in time.

lowerider57,

You’re absolutely right,  As I mentioned, the tests were only preliminary.
I haven’t given the Amperex enough time yet to burn in yet.
Im going to leave them in for a while to give a more thorough evaluation.

Thanks to all of you that gave advice about NOS tubes.
They make a HUGE  difference in the sound of my set.