Let's talk New Production Tubes (non-NOS) --- 12AX7

Discussion in 'Audio Hardware' started by TheVinylAddict, Jul 24, 2018.

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  1. samurai

    samurai Step right up! See the glory, of the royal scam.

    Location:
    MINNESOTA
    I've got a pair of new Sophia Electric 12AX7's. Does anyone know who makes them?
     
  2. allied333

    allied333 Audiophile

    Location:
    nowhere
    So far the best sounding 12AX7 is simple and tests for best sonics yields same results in many different amps. Mullard 12AX7 round getter long plate works best and outperforms any new manufactured tube sonically. The Mullard 12AX7 long plate square getter is slightly better, but high cost may not be worth it. If you need a little more detail, the Raytheon 5751 windmill getter is also great but not as smooth sounding as the Mullard 12AX7 long plates.

    Buy a few matched pairs of new manufactured tubes and you could have owned the Mullard 12AX7 long plates. Careful as a lot of used up Mullards are on ebay. Buy high testing tubes only. That is nothing less than 1400gm or on some testers 44 or higher.

    Sorry to 'bust bubbles' here, but it is what it is. Buy once and never look back.
     
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  3. octavius

    octavius Forum Resident

    Location:
    Slovakia
  4. chervokas

    chervokas Senior Member

    #1 -- @allied333 is talking about old production UK-made Mullard from the '50s and '60s, tubes that haven't been made in 50 years. That chart refers to tubes made today in Russia by New Sensor, the same company and plant that makes Electro Harmonix, Sovtek, Gold Lion, and "Mullard" and other tube brands that use great old brand names of tube makers of the past. But those New Sensor "Mullard" tubes have nothing to do with old production Mullards. They don't have the same construction materials; they don't have the same design; they certainly don't have the same quality control. They're not the same tube. It's just a use of the great old brand name to market a new tube.

    #2 -- Forget sonic tests of tubes in guitar amps. Guitarist are looking for something completely different than hifi users are out of their tubes, and guitar amps don't typically put out any high treble (guitar speakers roll off pretty steeply above 3kHz), so those handy listening test chart published by sellers of tubes to guitarists aren't really going to be all that helpful to someone looking for hifi tubes.

    #3 -- Not everyone agrees with @allied333 that the Mullard round getter long plated 12x7 is the "best sounding" 12ax7 -- some people prefer others, Telefunkens in particular are popular. In my experience (and all my old Mullards now have gotten long in the tooth), the long plate round getter Blackburn Mullard 12ax7 has that great tactile presentation of timbre and midrange presence and "liveness" that Mullards (old Mullards, not New Sensor Mullards) are famous for; but don't have the detail and imaging focus of other tubes. They're smooth and have something magical in their presentation that's hard to define, but in the end I feel like they're always hiding some musical information behind their smoothness.

    #4 -- I think if you're buying used pulls to buy at least high testing ones is good advice. A lot of times a new tube will sound better than an great old production tube just because the old tube is weak and noisy compared to the new tube.
     
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  5. Have a side by side look at the GL-12AX7 (gold pins) and the Mullard 12AX7 not the 4004. They appear to be
    identical on the inside., well to my untrained eyes anyway.
     
  6. chervokas

    chervokas Senior Member

    Here's a piece Effectrode published years ago doing a physical dissection of a Blackburn Mullard and a New Sensor Mullard 12ax7. Besides the obviously physical differences it doesn't address any other materials differences like cathode coating formulation. Dunno about the New Sensor Gold Lion. But clearly with the two tubes dissected here there was no attempt to physically replicate the older tube with the newer: Mullard ECC83 (12AX7) Reissue vs Original – A Physical Comparison - Effectrode

    How and if these things impact sound is another matter (I've heard plenty of good sounding new production tubes; though I've come across few if any that are as durable as old ones).
     
  7. allied333

    allied333 Audiophile

    Location:
    nowhere
    Interesting read. Thanks.
     
  8. Thanks chervokas good read
     
  9. TarnishedEars

    TarnishedEars Forum Resident

    Location:
    The Seattle area
    Yes, with only rare certain exceptions the revival of the old brand names is just for marketing. Most new tubes have not attempted to replicate the internal structure of any small signal tubes, so far as I can tell. Although this is much less true of power tubes like EL34s, KT66, KT77s, and KT88s where a great deal of effort has been made to replicate the original classic designs as closely as possible.
     
  10. chervokas

    chervokas Senior Member

    I dunno about that, have you seen a dissection? I mean none of the new EL34s can have plates that can dissipate heat like old Mullard Blackburn EL34s. Those suckers you could idle near max dissipation and they run on and on; these new tubes, if they get withing sniffing distance of max dissipation they'll red plate. And a bunch of old amps like the Dynaco ST70 and some of the Eicos, which came with Blackburn Mullards as factory tubes -- you really can't idle them at the design bias points with contemporary tubes, because the tubes will crap out.
     
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  11. TarnishedEars

    TarnishedEars Forum Resident

    Location:
    The Seattle area
    I didn't say that the quality was up to the old tubes, nor that they spent as much on the materials to make these nearly as well. But many have attempted to duplicate the physical construction of the originals quite closely. This, as compared to any of the current 12AX7s out there, none of which bear even a fleeting physical resemblance to the original tubes who's names they now bear.
     
  12. I think the best current production tubes are the TJ Full Music 12AX7 or the Northern Electric 12AX7 which are actually the same tube,made at the same factory and that get the same outstanding sound that put Gold Lion 12AX7 with golden pins or Psvane 12AX7 Mk II to shame.
     
  13. SandAndGlass

    SandAndGlass Twilight Forum Resident

    On a good day, the maximum plate dissipation (of modern EL-34's) will be about 25-Watts.
     
  14. macster

    macster Forum Resident

    Location:
    San Diego, Ca. USA
    I respectfully disagree. I have North Elec 12AX7 and in "my system" the Golden Lion kills it. Let me rephrase that a bit, the Golden Lion produces a sound that is more to my liking. But I do own both Brands, the North Electric are tucked away nice and tight in their metal cans. This is another example of where system synergy plays a factor.

    M~
     
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  15. chervokas

    chervokas Senior Member

    Well, that's spec for an EL34, isn't it. That's always been the spec I think. But the old EL34s could take that and then some and keep running for 50 years. The new ones get close to that and fry up.
     
    SandAndGlass likes this.
  16. SandAndGlass

    SandAndGlass Twilight Forum Resident

    I really don't care that much for new manufacture EL34's. I bought some NOS RFT's for the L5 Audio Note Kit amplifier. They do cost more than modern tubes, but they have a refined sound that modern tubes don't approach.

    And for NOS, they don't rape your bank account, the way that the NOS Mullard's and Telefunken NOS tubes do.

    I figure, you factor in their longevity factor, and I'm ahead of the game, all the way around.

    For new manufacture tubes, I prefer the KT88'S over the EL34's. New manufacture EL34's are hit and miss, both with the midrange and in the bass department.

    The KT88's have both these bases covered. I realize that some people think that KT88's are flabby in the bass department. You take a modern KT88 and pair it with an amp of modern design, like the Rogue's that I have and the PrimaLuna Prologue Five, which is currently running the Zu's, and you get a nice rich midrange and strong natural sounding bass.

    Plus, the tube has an extra 10-Watts of plate dissipation to play with and a larger bottle for better heat dissipation.

    Another advantage of the NOS RFT's, they are available and at somewhat reasonable prices. Try and buy any NOS KT88 tube and you will be giving up your retirement income.

    My latest amp is a Line Magnetic 845 based 518iA SET, which is an end game amp for me and the A7's. It can be run as an integrated or simply as a power amp. I have a nice 6SN7 tube preamp, so I'm running it as a straight power amp and it is everything a natural sounding amp could be. I did change out the stock 12AX7's for NOS late 1950's RCA black plates. But the power tubes are stock.

    I am completely satisfied with the frequency range and the dynamics of the stock tubes. With the A7's, the 22-WPC is more than enough authoritative power to drive the A7's.

    Even with the tube rectification, the bass is deep, strong and not at all flabby. This is really the first time that I have been totally satisfied with the bass on the A7's without the large sub in the circuit (this is with tube amps, but not including the powerful Rogue amps).

    I wouldn't pay the prices for the more expensive 845's. When you get into these powerful output tubes, they might only average 2k hours, unlike lower power tubes like the 300's which are more likely to last a lot longer, and I like to listen to my tube amplifier's!

    One advantage to the SET design, is that, even though modern 845's are more expensive than KT88's is that, I only have to buy one 845 instead of at least two KT88's per channel.

    Every time that I light up the Rogue M-150 monoblock's, I'm burning EIGHT KT88's, OUCH!

    Given though the Line Magnetic and the Rogue's are about the same retail value, I'll take the LM.

    Fortunately, I have the super efficient and excellent sounding A7's, which don't require as much power as other speakers might.

    I've been on a quest not only for better sound, but at lower operating costs.

    I also have the LM 218iA and I am running modern KT77's in it, which I think sound better than modern EL34's.
     
  17. allied333

    allied333 Audiophile

    Location:
    nowhere
    If you have EL34 and want a 'tighter' sound, buy Genelex KT77. Quad is around $140.
     
    SandAndGlass likes this.
  18. Are you currently using your Northern Electric 12AX7's? Are they broken in or do they have a lot of use?
    My Gold Lion with golden pins 12AX7 have 120 hours of use, not more, I got them with my first Phono preamp two years ago and as I was new to tubes I counted every hour of use and took note of them to know the hours of use and how they changed with time. They have always sounded good to me but not outstanding so I then got a pair of Psvane 12AX7 Mk II (in their box) and they sound different to the Gold Lions, more transparent after another 140 hours of breaking in.
    As I was still not satisfied I tried with cheap NOS, I first got a NOS and NIB pair of Hitachi 12AX7 and looking for more I got two pairs of NOS and NIB Hit Ray (Hitachi-Raytheon, made in Japan) and I love their sound,being the Hit Rays the best of the two.
    I also have three pairs of NOS Matsushita 12AX7 and I think they're great, much better than the Gold Lion and the Psvane, but cheaper.
    I also got a pair of RCA grey plates 12AX7 NOS and NIB, they sound fine but were not (I sold them) anything special to me.
    But as I'm always open to improve the sound of my Phono preamp and I don't mind if this comes in the form of NOS or new Production and after reading a couple of good reviews of those TJ Full Music 12AX7 tubes I had never heard or read about before I looked for a pair on eBay and I bought it. As you well said, synergy is a key factor and the TJ full music sound terrific on my EAR 834 "clone" Phono preamp, their sound is really outstanding and (sorry, I don't use to be cozy) a beauty on it. I love them and I have another pair on the way as it seems they're becoming scarce maybe because most of the production from their two factories is going to the Northern Electric brand.
     
  19. macster

    macster Forum Resident

    Location:
    San Diego, Ca. USA
    I also love the CV4004 in the phone position. My outlook on this is that I'm going to purchase the "best" tube that I can for a reasonable price. As a result no NOS for me, and in my situation ignorance is bliss. :D


    M~
     
  20. chervokas

    chervokas Senior Member

    They haven't made an attempt to duplicate the physical construction closely if they haven't used comparable materials, equally tight tolerances, etc. All they've done is something cosmetic and superficial if they've made them look similar without they matching materials and manufacturing techniques.
     
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  21. E.Baba

    E.Baba Forum Resident

    Has anyone tried the new Shuguang 12ax7 black glass tubes?

    Their black glass KT 88 are superb.
     
  22. Geoduck

    Geoduck Well-Known Member

    Location:
    Left Coast PNW
    I've tried the Shuguang Black Glass 12AX7 it's similar but not identical to Psvane 12AX7 Mk II. I buy Chinese tubes from Rachel at Grant. Both are very musical natural and quiet.
    Gold Lion reissue is a great sounding tube.
    Sovtek 12AX7LPS are quiet and tough but a bit dull and muffled compared to some top tubes.
    EH 12AXEH are a great value but modest sounding dull with a bit of grain and hard. This tube is reasonably quiet in non critical applications OK.
     
  23. RemyM

    RemyM Forum Resident

    Interesting threat. I'm new to tube rolling. I bought a Croft 25/7 combination with a separated Croft RIAA phono amp. All of them have the stock JJ ECC83S valves. I was wondering, and i know it's different for everybody, if there is a valve that's in general or overal better than this stock version that comes with the amps.

    Second, would it be better to start rolling with the pre-amp or the phono. Or is it just find out and suit yourself.
     
  24. fcdvpds

    fcdvpds Forum Resident

    Location:
    Hong Kong
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  25. RemyM

    RemyM Forum Resident

    Thanks. My Chinese is lacking lately and i don't have Facebook. But gonna try to find something.
     
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