So I bought a Pro-ject Pre Box RS... (Valve suggestions?)


The Pre Box RS comes from the factory with Electro Harmonix 6922, on the output stage. All I have read about this pre has suggested a linear power supply upgrade and tube rolling gives
significantly better results, so the linear PSU is already done (19VDC from a HDPlex 200W).

I've already got some tubes I bought for my old old DAC (it's now 9 years old).
I have a pair of Amperex P.Q 6922 [VCM 163 tested], and a pair of
Phillips E88CC SQ [1109] with writing on the box [12500-12750 and 12400-12500 on the other box] What do those hand written numbers mean?

Anyway, which valves should I likely go with? (I am hoping for longevity as well as quality)



 
296b8550 a8d9 491e b6ed 711d1b5106c4rixthetrick
tomcy6
I'm flying back to visit family in Australia, and while I'm gone I was seriously considering cryo treating my speaker cables and interconnects.
Should I send the valves in with it? Had any experience with doing that?
No I don't.  Can't help you there.
hi Rick, I have the Pre Box as well. How did you connect the Linear power supply you bought? Were you able to source a connector or did you run cables into the box to connect t? 
From memory it's just a standard female mini XLR connector, I think I got mine from Ebay. I put a multimeter on the original power supply (it's DC, so polarity was easy to check) and soldered to two pins of the three with the same polarity.
I have a HDPlex 200W linear power supply, which services my music server (fanless), FEMTO USB card, separate power for SSD's in the server, and of course the Pre Box RS.