Question for tube aficionados

Raindance 3-16-2018
They are also prone to oscillation with the wrong tube choices because of CJ's refusal to follow good design practice and use grid stopper resistors.

Interesting point, which I hadn't been aware of.  I couldn't find a schematic for the PV11, but I took a look at schematics for the PV10 and PV12 which are available at HiFiEngine.com.  And I can confirm Raindance's assertion for at least most of the tube stages in these designs.  I have no idea why CJ wouldn't have put grid stopper resistors having at least relatively low resistances into these designs, but as Raindance indicated not including them is definitely not good design practice.

The following article provides good background on this subject, even though it is oriented toward guitar amp applications:

http://www.aikenamps.com/index.php/grid-resistors-why-are-they-used

Regards,
-- Al
 

Just another note, if anyone knows more about 12au7, 12ax7,5751 tubes, it’s me. I’ve been rolling tubes for years and I have a huge stock of all the top vintage brands. I can’t believe how people comment on subjects they know nothing about. No wonder people get so confused when they need direction. 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.  I personally felt the phonostage of the PV-11 was way superior to its linestage and I actually found putting in all quality tubes in the phonostage didn’t improve its sound. So for the  phonostage, I used a vintage 5751 black plate triple mica (doesn’t matter their all great), basic current production Russian 12AX7’s and a Mullard 12AU7 or 7316 Amperex for the 12AU7. Good luck.  

Very interesting posts!
Also a myriad of suggestions.

I agree the phono stage of the PV11 is awesome.  Records sound way better than CDs.
Thank you lowtubes for your expertise.
 I will look for the Amperex 7316.

I owned a PV11 for many years... a truely wonderful preamp.  I loved it.

What is wrong with calling CJ directly and talking to them? 

CJ knows the tube market really well and can help you make a decision.. they have seen it all.  Getting other opinions is great, but why this apparent aversion to calling the manufacturer?   CJ is a good company with good folks who know what their stuff.

I would start with CJ first, then branch out.

Peace
Bruce in Philly

I did get CJ’s recommendation.  See above.