EL34 tubes- alternates to matched octet for Primaluna HP dialogue premium

So long as you are using the same brand/type you won’t lose much, if anything, due to the auto bias circuit in the PL amp. FWIW you have much to gain by considering different small NOS tubes, but not so much, I think, when considering power tubes which are usually verrry expensive and often not much better, if any, than some of the new production tubes currently available. Personally I would try new production tubes before going to NOS power tubes. In my Dialogue One I enjoy either JJ E34L’s or SED 6L6CG’s, the former warmer but having nice, clear highs, the latter a much more linear tone.

I have an HP as well and have used those NOS Mullards (the 8136 variety?) on my front end as well. Huge difference. Worth the $$ IMO and we are talking $120 per tube.

Theoretically, you can put 8 different EL34s in there and due to the PL self-biasing, it should work fine. but even Upscale Audio (kevin deal part owner of PrimaLuna) doesn't recommend this at all. I dont know the specifics, but makes sense on a  common sense level.

@newbee makes a good point about trying modern production tubes  before the greater expense of a full Octet of NOS tubes. But sometimes I want to take my upgrade climb 2 levels, not just one. The new production tubes get you 1 level. NOS gets you 2-3 levels higher. 

To save some money and intermediary steps, consider going straight to NOS if you will be using that amp for years to come. If you get the 8 modern tubes, listen for a month, then desire to go up to the next level, then you've got 8 tubes on your hands to have to sell. 

IMO< any upgrades to the PL HP integrated helps the whole system. It think of it as a great foundation/blueprint to build on with tubes specific to your system and room. 

If I had your integrated I probably would be tempted to try the kt150s just based on all the favorable reviews. They will not work in my El34 amp. I have used old stock mullards and a few new production tubes. But the best has been the Gold Lion kt77s I purchased from Upscale Audio.

There are several references to the PL integrated.  I have the power amp version, running a separate preamp.  I assume the comments apply to the power amp version as well as the integrated.

to 1graber2- yes the 8136 mullards at 120 each.  Might be the best money I have ever spent for a sonic improvement, best bang for the buck.

Get you two matched quads of Shuguang 6CA7-Z 50 Year Treasure Tubes (Black Bottle) and just kick back and enjoy the music, have had great luck buying these from a couple different venders on Ebay, just remember to get their premium grade.