Primaluna - Rolling pre tubes question...

I'm new to rolling tubes, and have been using the stock 12AU7.
I've a PL Prologue premium integrated with 2 12AU7's per channel. I want to test a new pair(before investing in more), so wondering if front or rear position would best reveal the new tubes character?

I think that Kevin Deal/Upscale would be the first place I would buy upgraded 12AU7s from, since they should know their own amps. You might just call them and ask where the tubes do the most good.
The two center positions will reveal a greater difference than the outer two. But, I suggest that power tube selection will have a far greater influence in the sound quality. If you haven't already done so, start there and then fine tune with the small tubes.
+1 for what Newbee said .
If you received your amp with the stock power tubes , they are decent . They should be Shuguang EL-34's with reddish brown bases . You'll get as many different suggestions as replies for powertubes to try .
What do you wish to gain or change with your tube rolling ?

Happy Tunes
I agree with them as well the power tubes have a greater impact on the sound than the pre tubes. I answered thinking you were set on your power tubes.
In general I am quite fond of the Gold Lion tubes now available, but I leave to you to decide which you want to try.
Thanks so much for the responses - I appreciate it. Navigating the forums can be daunting...

I should have offered more detail first - I have already tried 3 sets of power tubes over the past year: the stock EL34s - I really dig their midrange texture. Out of curiosity, and, for my own education I picked up a set of GL KT77s last summer (from Upscale - currently posted for sale) - these are nice, but not quite what I wanted. I ultimately ended up with PSVANE 6CA7-Z treasures - these are fantastic.

Now that I have the power tubes, I was thinking about rolling the stock 12AU7's. I believe the Cifte will bring the touch of air I want - was thinking I'd pick up 2 and see what they do.
Well now that you do indeed have your power tubes of choice. What sound are you hoping to get from the small signal tubes. That will be a tremendous help.
Since you didn't like the Gold Lions which lean towards warmth I don't think that British tubes would be what you want, but you may want to balance out your Psvanes with them. Please provide more info. Otherwise if you simply want strong clean transparent sound German tubes (e.g. Telefunken ??Siemens not sure they made a 12AU7) may be the answer albeit expensive.
My all time favorite are early 60s, late 50s Amperex which I think do it all, but are being counterfeited and subbed allover for big $$. And don't fall for the low noise 7316 variant if it not made by Amperex,(and often labeled a computer company) these are truly special but people are calling anything they want a 7316. They must come from Heerlen Holland with the right triangle and ctl with a # in the acid etch . Otherwise just look for Amperex 12AU7s to make it simple all have the Philips seamed top. The real Amperex 12AU7s are expensive the 7316s even a bit more. Sif you wanted a cheap option this isn't it.
I have the Primaluna Dialogue Premium , basically the big brother of your Prologue Premium . I have settled on the same power tube , the Black Treasure 6CA7 .
If you can wait a while I have some Amperex 12AU7's and some
7316's that I will be rolling in a few days with the BT's .
I was also thinking of the Cifte's as well but don't have any to try .
A less expensive alternative to the Amperex with most of the same characteristics would be some BEL's . They are the same design but made in a different factory (India) and time period .
If you do try some Cifte's , I would be interested in your opinion on how they do with your BT's .

Good Luck
Newbee - Appreciate the help.

Mechans -
Thanks for the recommendations - I was thinking about Telefunken, though budget may not allow it at this point. I'd say transparency is key, but balance overall suits my taste. I think the Cifte will add a touch of air and clarity in the mids...and based on at least one thread I'd read, this may come at the cost of bass definition. We'll see.

Saki70 -
I did order a pair of the Cifte, and will place in them in the front/middle position, and keep the stock tubes in the rear. I'll do some critical listening and follow up.

For reference: I am also a musician, and really dig tone, speed and dynamics (so like high sensitivity speakers).. so am less focused (though they are still important) on imaging and soundstage. Maybe I lean toward live vs. hifi?
I listen to almost every style in some form, though recent choices have been largely focused equally on small combo jazz and more experimental contemporary pop/rock. I've a modest system - and have just 2 years experience with critical listening to tube amps- so will try and focus on direct comparisons between the Cifte and stock PL 12AU7s.

Hopefully this will be useful.
Thanks again

PL Prologue premium integrated/Tekton Lore/Parasound zdac.
If the Cifte's take you in the right direction , you may want to try them in the driver position also . The two front/middle tubes control the input section and the two back/outside tubes control the driver section .
Some people will experiment further with different tubes in each section to further tailor the sound . There are many possibilities !
Have fun and let us know how it goes .
One week with the Cifte 12AU7s in the front position, and PL stock tubes in the rear. I'm assuming they may still be settling in...probably 40 hours or so on them.
I'm hearing clarity across all frequencies - not harsh - more like we've turned the light up in the room and the back corners are illuminated. Really nice.

With some recordings, a lack of humidity is revealed...perhaps a bit papery at times.

Would a Mullard or other similar type in the rear position balance the sound? Mechans -You mentioned the British tubes?

Take for instance, a well recorded drum kit...I want all that air and resonance, and maybe a touch of fuzz on the kick drum...More tennis ball than rubber ball.

I'm missing the luscious mids and upper bass.
Yes there are classically warm British tubes like the Mullard ECC82, the Philips Miniwatt, Mazda,and even Valvo (which is as likely to be German so be careful, etch code is your ally) and the Mullard Mil Spec 4003.Another British tube that glides under the radar that is the more neutral sub made by Brimar the 13D5. I am sure you can find Mullards to try., but if you didn't like the reissue Gold Lions not sure you would like these either. Did you try the small Gold Lions? I forget but does the treasure series include some of the pre amp tubes?
Hi - I have a Dialogue 2, and I had a 12au7 go out on me, so I bought a new pair, and they were not as good as the stock tubes were - the stock au7s in the PrimaLuna amps are pretty good. Next time, I will be buying them, as they were also less expensive than the ones I did try. I have not done a ton of tube rolling, but like many others here, I prefer the sound of EL34s to the KT88s in the Dialogue 2.
Learsfool, I had the same experience, after rolling all of the tubes in my monoblocks; I quickly put the 12au7's back in.
Dmhenley ;
I am sorry the Cifte's didn't work out for you .
If the price doesn't scare you... try some 7316's in the input section . Far & away the best that I have tried to date .
For less money you could try Amperex made by BEL in India which would give a good taste of the 7316's . Both of these offer a warm tone . The BEL's may be around the same price as the Cifte's .
Amperex 12AU7 D getter long plates were not to my liking in this position . I have not tried Mullards with this amp but did use them in my previous amp , a Prologue II which used 12AX7's for inputs .
I tried Amperex Valvo's for drivers and they didn't work out either . The Valvo's tended to take away what the 7316's brought in , as did others that I tried as drivers .
I have not been able to find other tubes for the driver section that don't detract from the various input offerings .

Learsfool & Orpheus10 ;
I have been thinking along those same lines concerning the PL 12AU7's , they seem to be rather neutral also . They allowed me to here a large difference between the KT-120's and the 6CA7's when used as inputs . The difference was less prevalent with other tubes rolled into the input section . So far they are the best drivers that I have tried , allowing me to hear all of the different tubes that I have rolled .
Saki70 -
I do like the Cifte's, but I did lose some presence in the mids and upper bass. Much like all of your experiences were, I found swapping the stock PLs back in brought me back where I want to be.

Eventually, I will continue to experiment - this is all good education for me.

I think I'll enjoy the music for a bit before I go down the rabbit hole again.

Thanks again
That's may find that what you have ain't so bad !

Happy Tunes
I'm about to put up some info on the PrimaLuna website about this. First, in preamps all the small signal tubes have an equal effect on the sound and you can change out just one pair if you want.

On power amps and integrated amps the two 12AU7 (in older models 12AX7) that are in the center are the input tubes and they have gain, so they will make the most difference.

I've spent a lot of time on this. The stock tubes are surprisingly good sounding. Fabulous. The French-made 1962 vintage Cifte's will have a little more extension on top, and that's why the mids are not as up-front. But that will change in time. They have a lengthy break in period. I would say a couple hundred hours. But really it takes longer than that.

I've been running 60's vintage Mullard M8136 and they are really nice. I don't know if they are for me exactly. They have more body. The mids are fuller and pretty. But the reason it sounds this way is because it's more laid-back on top.

I've also tried some British-made Brimar CV4003. These are hard to find, but we recently scored a nice quantity of perfect ones. I've always liked them. They are between the two above.

I have customers with really good ears tell me that they love the stock tubes and I agree. I hope this helps. If you guys have questions on this it's really great to put them up here or audioasylum as others DO benefit even years later from your data.

Mechans ;
Yes , Psvane does make a TII 12AU7 . But I have not found been able to find out much about them .
I never invested in a pair of the fancy recent treasure or Psvane tubes believing that they were marketing ploy for Shuguang or Sino brand tubes in a pretty bottle. I had liked the Sino 12AX7 9C version. I think that is it -it is so long since I had used them. They made them and then stopped and just make the 12AX7 8 B. Beats me but I see that Uncle Kevin (Upscale) has made a few comments, I would trust him as I had advised right away.
I've had great luck with ciftes in my prologue 3. The ciftes seemed to extend or clean up the top a bit and added what my wife and I could only describe as 'velvet' to the sound. Mind the break in time though, I have had the same experience noted earlier in this thread. I've found I need 100+++ hours before even starting judgment for either new or NOS. Broken in PL tubes sounded way better than NOS...for a while.
Thanks Kevin for the update. Mine isn't near broke in but so far I like the sound with the stock tubes. I ordered KT120s when Kevin shipped the amp but haven't rolled them yet.
My experience with Black Treasures versus standard Sino tubes is that the Black Treasures have more body to the sound - richer, more detailed
Thank you Kevin!
This thread has been very helpful for me.

And I have found exactly what you've described with the Cifte. I have them back in the center position, and they have settled in - Very happy overall.
I've lived with the Primaluna Premium integrated for about 2 years, heres where I have settled

1) tube dampers a must... subliminal screechiness for female chorus and strings otherwise that eventually becomes irritating.
2) Kt-150's work wonderfully all around for power tubes but give up some vs EL34 on the human voice. But the EL34 can't do cymbals right.
3) Telefunken 12AU7 hard to beat for all 4 small tubes
4) Amperex/Holland Bugle Boy 12AU7 in front sockets with Telefunken 12AU7 in back is also very good and a little more mellow
Hi Davide256 I've never used tube dampers in a PrimaLuna. I'll try some for fun. Tube dampers are never "always good" or "always bad" as it depends on that single tube in your hand. A little bit of microphony can be good. It's something you have to try.

I am so glad we went with as many 12AU7's as we have. It's great for tube rolling. There are some new PrimaLuna products coming out that will use 12AU7's and 12AX7's come January.

There will be a tube headphone amp that can be run two different ways. And incredible phono stage designed in a way I've not seen before. And a DAC that is all-tube, dual mono, tube rectified, and uses a tube to address jitter (only found in PrimaLuna)

They are in prototyping now. I won't say anything more. I was supposed to keep my mouth shut.
Not a fan of ceramic sockets for pre tubes like the PL Premium integrated has, much prefer Teflon or composite sockets for better damping at the junction of socket and glass bottom of the tube. Microphony is distortion, pure and simple, never good.
Hi David256 if you look at many products that use tube sockets they are mounted onto PCB's, and it's not uncommon to have that same PCB have the power transformer attached to it. PrimaLuna tube sockets are mounted on to heavy-gauge fully ventilated standoffs. The chassis is so heavy I don't think there's a lot of microphony going on.

It's so easy to demonstrate. You can whack the hell out of the chassis and hardly a peep will show up anywhere on any PrimaLuna component. Compare that tube a number of preamps where you simply flip a switch and it rings through the speakers.

I do like composite sockets too. We used some killer ones when we built the Ah! Tjoeb CD player that were da bomb. But the ones we use never fail (well, maybe one) so that's what we're shooting for.

On the microphony question, I've found that tubes can lose a little air and harden up with dampers SOMETIMES. Every case is different. Some microphony CAN be good, evidenced by the sound degrading if it's removed. Is it a distortion artifact? Maybe. But that's one of the charming aspects of tubes. If distortion were the end-all be-all buy an Aragon. They are electrically perfect.

If the tube is already low in microphony, and the circuit isn't a silly one (like this idiocy of 27dB of gain in a preamp), and the socket isn't mounted to a PCB, why bother. It should be done on a case by case basis. What ever sounds best. They cost nothing so why not.

I have a PL Dialogue Premium preamp and I am looking to buy a few tubes.  Just want to be clear so that I don't waste my money.  I only need to replace 2 or 4 of the 6 12au7s?  Please advise!  Thank you.
The 2 front tubes are all you need to replace. They have the most affect on the sound. 
If I can get away with only switching out 2 tubes (1 pair) then I can really splurge!  Just to be clear, this is for a preamp.  Thank you.
Oh my bad I overlooked the fact it was a preamp only. I've been so focused on my integrated so I am not sure. Have you Googled or searched Audiogon in the meantime? 
Kevin wrote, " First, in preamps all the small signal tubes have an equal effect on the sound and you can change out just one pair if you want" which confuses me.  If they have an equal effect, would you not have to change out all of them?
Maybe what he is saying if you change out 1 pair it changes the sound significantly to the characteristics of that tube and the rest doesn't have quite that much of an effect.  Make sense?
I don't know about yours, tswisla, but my integrated has 2 ax7's, and 2 au7's for the preamp part of the amp.  So Kevin means that you can change just one of those pairs, and it will make a significant difference to the sound.