Best Tubes for VAC

I ran both in a prior system incarnation, albeit the original Ren Sig IIa, not SE.  My IIa only had 8416's as the line stage tube, so I couldn't roll, and there is only one 8416, so no flavors to try (the 12AU7's are used as tube buffers for the tape monitor section, IIRC),  Just by experience and reputation I would seek out some Telefunken NOS to try, as they typically excel at transparency and articulation (too much so for my tastes in some other gear, but it all depends on gear and system matching).

For the PHI 200 I ran most happily with the new Gold Lion KT88  "reissues".  Now, I liked them because they had a fuller harmonic presentation, but I did not feel they did so with any lack of detail.  I found that the VAC supplied tubes were too shrill in my system, so I may not be the best adviser, given the direction needs you have.  My system at the time needed a wee bit of warming to hit the right overall balance.

I can't comment on the preamp, but for the power amp, shuguang WE-KT88 plus and their WE6SN7 red base fat bottles.

most open, organic sounding KT88 I have tried.

Hi Peter,

I also have a MkIIa SE preamp that is not an upgraded unit. Interestingly, there are no 12AU7 tubes in the power supply.

Currently I’m using a pair of Amperex 6922 PQ gold pins made in the US. They are transparent, detailed and tonally accurate. The soundstage, imaging and dispersion are incredible with these tubes. As jbrrp1 stated, the Telefunken’s may also be what you seek. I’ll most likely buy a pair of the white label, bottom diamond marked German made Telefunken’s to compare. Brent Jessee’s website has a lot of excellent info. http://www.audiotubes.com/6dj8.htm

HTH.
Ken

I think you probably have the best 6SN7 tubes for your Phi 200, given your sonic preferences (I like a slightly richer sound, so I use NOS RCAs, but Andy Bouwman of Vintage Tube Services, who sold me the RCAs, recommended the Sylvanias if I wanted a cleaner, more transparent and detailed sound).  I have had no problems (shrillness or otherwise) with the sound of the KT88s VAC sold me, using the RCAs.