Best cheap NOS tubes:GE, Phillips and Sylvania

Being up there, you are best off finding the cheapest 6GK5 you can get and weeding through them yourself, esp if on a budget.

The tubes need to be very low in microphony, and not likely to become microphonic OR noisy. That's not an easy task for the PV-10A, PV-11, and PV-12. Not easy for a CAT either.

They used RFT for a while at the factory. Those worked fine. Mullard sound better. I might suggest using the box plate version called a CV4003. They seem to hold up, if you get good ones to begin with.

Rocc - I'm very happy with Mullards in my premier 14 over stock GE and Sylvania. Try Upscale audio, at the very least you should have different types of tubes to experiment with. I was using stock for a while and switched speaker cables from Kimber 8TC to Alpha-Gore MI2's and the stock tubes sounded a little aggressive on the top end, especially on bright digital recordings. The Mullard's in this case are a better match, much less fatiguing, instruments sound more life like IMO....

dont think so because cj ten is a warm pre-amp and mullard is warm sounding tubes

Are Mullrd NOS 12AU7's a good match for a CJ PV10A pre-amp?

I would do as Frogman suggests, the Mullards are light years ahead of the GE, and Sylvania.

I can hardly tolerate the Phillips, so the comparison there is difficult to even comment upon.

Try Ken Chait at Advantage Tube Services
http://www.tubeman.com
561-434-3799

I have on two occasions bought NOS Mullard 6GK5's from him on auction at EBay; for about 4.00 a tube. A steal!

http://www.thetubestore.com/

They're in Ontario, no hassles