Mullard cv4003 & 12au7 Blackburn

I'm using the Primaluna Dialogue Premium preamp.

This only has 4/6 gain tubes so I should of stopped there. But I asked him what he thought if the cathode followers were worthwhile to change out. He didn't know what the Primaluna stock brand tubes were but guessed they were modern-issues from Russia, China or Czech Republic. I don't know if anyone knows what PL's rebranded stock tubes actually are. His opinion, very boldly so, was that they're all crap in comparison to the older ones and won't last as long either. I kinda took this with a grain of salt but decided to go for it anyways because I'd wonder. In the end if the cathode follower tubes don't change anything, it wasn't a huge expense and if anything they'll last quite a few years.

Regardless for my setup, the highs were too shrill and the mids a little recessed. He said the Mullards would be a good match for this as they're the darkest tonally he has with a rich and lush midrange, with the RCAs second slightly more towards neutral. The Tele's Tungsols and Amperex were neutral to airier/detailed/forward.

I will mix and match between the sockets and see if there is any combo that sounds the best. Mullards have such a following that I gotta try them :)

the highs were too shrill and the mids a little recessed.

I've been there. Mullards are the way to go. The cathode follower does influence the overall sonic signature, but less than the front tube, of course.
I've used Mullards for gain and RCA Cleartops as followers. You get the Mullard sonic signature with some air at the top-end.

Let us know how it turns out.
Oh yeah, what did Andy say about the CV4003 tube?

I think the Primaluna stock tubes are made by Shuguang for PL.  

I've tried a ton of preamp tubes in my PL Dialogue Prem. HP integrated.  I like Ciftes, Mullards, GE military spec.  RCA clear tops are really bold and aggressive, which is fun but a bit too forward for me.  I sometimes mix a couple cleartops with Mullards or Ciftes with Mullards. 

@lowrider57 I actually forgot all about it haha. Guess it doesn't matter now. The price was way less than Upscale Audio's $110USD CV4003 and I'm sure 60's Blackburn Mullards were quality.

Mixing tubes sounds like a good way to go. Thanks gents!

Good deal, @msommers . I've bought from Andy four times and all his tubes have been of outstanding quality.