NOS Tubes for Premier CJ 11a

[Truth71]

Hi Everyone,
I'm looking for suggestions from people who have actually retubed a Premier 11a with NOS tubes. I'm NOT looking for suggestions re: changing the pwoer tube type ( ie change the 6550 to KT88, or KT 90, or KT 120 etc series) or impressions of tubes in other amplifiers.
For those who haven't memorized it, the Premier 11a tube requirement is:
V1 and V2 5751
V3 and V4 6FQ7
V5, V6, V7, V8 6550
My goals:
-Extended "Tuneful" bass response- NOT "THUMP, THUMP"
-Extended and airy highs (NOT etched or fatiguing)
-Magical Midrange ( as I hear more often in amps with EL34 vs 6550 power tubes)
-"It just sounds right" "tube Magic" CJ traditional Sonic Priority
-Longevity and Reliability
My understanding is that the Premier 11a was voiced on GE6550A power tubes....I do not know the original signal tubes.
I'm not trying to make a "collector statement" or create a museum piece...if people tell me for example that NOS Tung-Sol 6550, or Sylvania 6550 in their experience did the job better, I'm open.
But real experience in a Premier 11a please, no fantasies .
Thanks in advance !

[Joe Appierto]

I owned the 11A for a number of years and loved the amp.

Its original tube configuration was all GE: both small signal and output. The 6FQ7 was used as the driver/phase inverter and it was the successor to the 6CG7. The difference is that the older 6CG7 used an electrostatic shield which the later model dropped. The shield was said to reduce noise. C-J didn't have pin-9 connected so electrically it shouldn't have made a difference between the two. I used both and couldn't tell the difference between them in that regard. To me the differences in that tube position were determined by brand used and not type.

I don't need to tell you that equipping the 11A with NOS tubes is not going to be an inexpensive proposition but in my experience it did yield the best sonic results.

Regards,
Joe

[Big Dog RJ]

I'm with Joe here. Spot on Joe!
Infact, I remember you had the Prem140 and the 17LS wasn't it? Why on earth did you ever sell those beauties Joe? I know you had your reasons and you did mention it but those are rare pieces of fine musical instruments!

Anyway, getting back to the OP's post on the Prem11A:
With the Prem11A I never tried NOS tubes solely because NOS tubes don't really do anything that significant in improvement for me other than over expenditure...

I only used the recommended tubes provided by CJ at the time with one exception being the 6550's. When I reordered a second set, LJ recommended the 6550C SED tubes, and they were better. Now how do you define better is the question; well I could say more defined all round, bit more solid in lower bass and a wonderful midrange, perhaps more open and extended in a 3D sense. However, this improvement may account to 5-10% so it was nothing major as compared to an SE upgrade, where you would pay for items such as Teflon caps and metal foil resistors or Vishays etc.

I don't think the prem11A was voiced around the GE6550A tube. At the time the premier series amplifiers were offered by CJ, there was another triode version called XS. This modified the internal resistors slightly along with a few mods to the output bias on Class AB, which had to be done by CJ, and fitted with EL34's. After this XS version was done, it would halve the output stage to the following:
Prem11A xs 35w
Prem12 xs 70w
Prem8A xs 140w

We ordered a set each of these XS versions, and although power either doubled or tripled in standard 6550C pentode version, the overall musicality on the XS versions were superb! Although I must say they were highly coloured, it was a totally engaging experience, something that we enjoyed for many years and where a majority of other top end amplifiers just couldn't keep up, no chance!

So, to answer your question Truth71, Re. To using NOS tubes and what you're going to get out of them and the list of parameters you've stated, is basically something that you are looking for. This is a custom sound, very similar to what I've done with my current system developed over the years in Aus since 2004.

You would need to try them out for yourself and jot down notes and seek what you're after... It seems like judging from your concise list that you do know exactly what you're after, however none of us CJ passionate enthusiasts have the same hearing. Hence, this type of sound you're after is a personal benchmark.

All the best in your journey with the NOS brigade.
Cheers, RJ

[Joe Appierto]

You have a good memory, RJ. I did indeed used to have a 17LS that was succeeded by the 16LS2. One nicer than the other. I moved on from the 140 and the 16LS2 because I'd become obsessive, no better way of putting it, in trying every possible tube type and combination thereof in those units. It became really expensive after a while.

There was an American personality named Will Rogers in the early part of the 20th Century. A quote attributed to him was "I never met a man I didn't like" and to me c-j equipment was that way when it came to tubes. The equipment did, in my experience, like some tubes more than others.

AFAIK the GE6550A was c-j's go-to power tube in the 6550 application prior to the SED =C= 6550C. I remember reading this review in the February, 2004 issue of Soundstage! by Tim Aucremann:

"The 140 is the first Premier amp voiced from scratch with an all-Russian tube lineup. An obvious rationale is that the Svetlana 6550C is in production and available, while the GE 6550A -- C-J’s power tube of choice for the predecessor Premier Eight and Twelve -- is not."

That was the basis for my comment regarding the GE 6550A but I've been incorrect plenty of times before.

Regards,
Joe

[Truth71]

I’m hearing that the Premier 11a was voiced with the GE 6550 solely because TungSols were no longer widely available, that Tungsol designed and developed the tube and sonically as well as longevity wise Tungsol, if cost is not a consideration, is the tube to get ...no competition. Comments?

[Big Dog RJ]

When I first ordered the Prem 11A, it came fitted with SED 6550C tubes. I'm trying to remember the exact year of orders we placed.... I believe it was around 99/2000 when we took first delivery to try out on the Maggies MG3.5/r, actually initially on Paradigm speakers then Maggies.

This particular tube was recommended by LJ himself and matched and tested by Ed D at the time, so I wouldn't think the Prem 11A was voiced around the 6550A. However, your probably right because the Prem 11 first came out as the Prem11. A few iterations changed and they introduced the 11A, it was the 11A that came with the 6550C tubes and not the earlier versions. Also in the earlier versions the tube cage looks very different.

Anyway, really loved that amplifier, if there was ever a chance to own one again, I wouldn't hesitate for one moment. Obviously it was surpassed by quite a few units after that year. Beginning with the MV60SE, LP60s, Classic 60/se and now the Classic 62se. Looking at all these amplifiers side by side, and having owned all of then at one point, given the fine musical presence all of these possess, there's just something phenomenal about the Prem11A. It's not the sound because that level of fine quality was surpassed in the latest offerings, I think it's the build quality of the Prem11A. That beautiful gold champagne finish on its front face plate and top plate, plus the gold tops on the transformers is one of a kind. Simply gorgeous just to look at let alone stare at for endless hours once those tubes get glowing, Brilliant!

Enjoy those fine tunes on that Prem 11A , you gotta love it!
Cheers, RJ

[Joe Appierto]

It all comes down to personal preference of course. That having been said I tried dozens of different tube brands in my 11A and my three favorites were the original Tung-Sol 6550 black plate, solid grey plate and three-hole grey plate. Just my 2¢ naturally.

[Truth71]

While waiting for NOS tubes, I installed a New replacement set of tubes from Conrad Johnson. WOW!!!! Never heard a Premier 11a sound this good! Tight extended bass, wonderful mids,extended but NOT fatiguing high end. A bit more forward presentation, but only have a few hours on the tubes. “Pricey”? Depends on compared to what. Nice job Conrad Johnson !!!

[Big Dog RJ]

Truth71,

Great to hear that CJ's recommended tubes were a very good match. Certainly sounds like they've provided you with the best so far. Which exact type and brand did they send as replacements?

Also, was thinking perhaps since now these tubes are working mighty fine and delivering all the musicality required, you probably wouldn't need the NOS tubes afterall but then again you could always compare, just to experience the difference in performance, if any...

Cheers, let us know your thoughts.
RJ

[Truth71]

Hi Big Dog,

6550- New Re-reelase Tung-Sol
5751- Sovtek
6FQ7- NOS Sylvania

Again- Wow! Synergy must beat work here.

I will be trying to get NOS Tung-Sol 6550 and well as NOS 5751 nd 6FQ7....Andy at Vintage Tube is researching...if only to satisy my curiosity.

[Big Dog RJ]

Ah! Nice one indeed. That sounds mighty fine.
Enjoy to the fullest mate, those tunes will be singing with those wonderful tubes a glowing...

Cheers, RJ

[Carl]

I intend to replace the tubes of my premier 11a. Tungsols 6550 and Sovteks 5751 is no problem. I can not find Sylvania 6FQ7. Which tube is a proper replacement?

[admin]

I intend to replace the tubes of my premier 11a. Tungsols 6550 and Sovteks 5751 is no problem. I can not find Sylvania 6FQ7. Which tube is a proper replacement?

https://tubedepot.com/t/tubes/preamp-tubes/6cg7-6fq7

https://www.thetubestore.com/preamp-tub ... tube-types

https://vacuumtubevalues.com/product/el ... 6cg7-tube/

[Truth71]

Also, Brent Jesse has many varieties if you are looking for NOS:

https://www.audiotubes.com