Best New Production 12AX7?

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by bscepter, Aug 5, 2005.

  1. bscepter

    bscepter Member

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    I'm looking for very low microphonics. I've got a Vox AC30CC which vibrates like crazy at the volumes I'm playing at. I need a couple of tough, reliable, warm-sounding ECC83s for V1 & V2. And I need volume.

    I've got a pair of GT 12AX7Ms in there now, but I can hear V2 starting to howl. I've got an NOS Mullard CV4024(12AT7) in V3.

    I don't necessarily want a real "high-gain" tube. At least I think I don't. If "gain" means "early breakup." I'm not looking for bone-crunching distortion. I need a clean-to-moderately-dirty tone -- with as much volume as I can squeeze out of this 30w amp.

    I'm looking at the Electro Harmonix 12AX7, which is supposed to be very low in microphonics and the JJ ECC83S (or is it 803S?).

    Anyway, what do you guys suggest?
     
  2. RJones

    RJones Guest

    I like the JJs. The standard 12AX7 is good for high gain and is warm. The 803 version is a good all around tube and has more sparkle. I've never had microphonics issues with either.

    The EH is ok, but I just can't ever be excited about EH, which is just selected russian stuff.
     
  3. Wakarusa

    Wakarusa Member

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    The new 12AX7 from Mike Matthews under the Tung-Sol brand seems nice. I'm testing a couple in amps and so far the tone is marvelous.
     
  4. calieng

    calieng Member

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    I use the EH12AX7s most of the time. David Allen ships them with his kits and his amps sound fantastic. I also know Randall Aiken said he stopped putting JJs in his amps becuse he said they sound a little compressed if I recall correctly. I swapped the JJs in my Invader for EH when I got it and it improved the dynamics of the amp a bit. Relabelled EH12AX7 tubes are also what Mesa is currently using for their preamp tubes.

    I do like JJ power tubes though. They seem to have good bass response.

    I'm sure NOS and some other brands may sound better but EH are the best bang for the buck IMHO.
     
  5. calieng

    calieng Member

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    You may be thinking of Groove Tubes. EH12AX7 is made exclusively by Sovtek as far as I know. But it is made to a particular EH design. It is similar to the Sovtek 12AX7LPS but with a short plate.

    The 12AX7LPS is not a bad tube either by the way.
     
  6. Wakarusa

    Wakarusa Member

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    The EH can be overly bright (really depends on your amp and your ears I suppose).

    The Sovtek LPS is a great sounding tube, but easily subject to microphonics -- I use 'em in heads all the time, but not in combos. Also note that the LPS is limited by a low heater/cathode voltage rating. No big deal in an anode follower (reg'lar ol' gain stage), but won't survive in a cathode follower -- like the tone stack driver in Marshalls or tweed Fenders.
     
  7. calieng

    calieng Member

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  8. Greggy

    Greggy Member

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    If it's reliability and low microphonics from new production that you're after, EH is the best in my opinion and experience. Also love the LPS and I have never had microphonics problems with the 3 that I own.
     
  9. iggles

    iggles Member

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    Lord Valve sent me some Tung-Sol 12ax7's for my komet 60 and they are great!!
     
  10. Killa-B

    Killa-B Member

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    Based on what you've stated for your needs, I would look at NOS 5751 or 12AT7 tubes. The gain is a bit lower (70% and 60% respectively), but the signal to noise ratio is much more preferable in these old tubes, and I get a great warm tone with either.

    You can score JAN Phillips 5751 for about 12-15 bucks, and a Mullard 12AT7 for about the same money. These are great rugged tubes and may be just what you're looking for.
     
  11. bscepter

    bscepter Member

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    I've already got a Mullard CV4024 in V3. If I bought two more and put them in V1 & V2, would I have a cleaner amp? Would the volume be reduced? I would like the amp to stay the same with regard to volume -- or get even louder, perhaps.

    I'm not worried about break-up. My P90s could break up a Hiwatt.
     
  12. Killa-B

    Killa-B Member

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    You may have a slightly cleaner/clearer amp. The change in volume won't be too significant.

    There are just a lot more good lower gain preamp tubes available for much much more reasonable prices these days. Try em!
     
  13. bscepter

    bscepter Member

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    Cool. If I get a couple more Mullards, are they likely to be resistant to microphonic howl? I'd probably get the mil-spec version, the CV4024.

    By the way, anyone try the TAD 12AX7s that Mojo carries?
     
  14. Killa-B

    Killa-B Member

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    I've bought several mullard CV4024 tubes from "BNBtubes" from ebay with great results each time. I've paid about $14 each for them, and they come in the original silk paper and white box.
     
  15. Blue Strat

    Blue Strat Member

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    Ruby STR 7025s are one of the best new production 12AX7s.
     
  16. bscepter

    bscepter Member

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    Huh. I thought Ruby was just a tube matching service, putting their logo on Sovtek and Chinese tubes.
     
  17. Blue Strat

    Blue Strat Member

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    Almost. They do have some exclusive items like this one.

    They rebrand Sovtek, JJ, EH, EI, etc as well.
     
  18. bscepter

    bscepter Member

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    Cool. Thanks.

    Last question... what's the best value in low-microphonics NOS or ANOS tubes? I see you've got some ANOS Mullards there for $55. Anything worthwhile in the $30-$40 range?
     
  19. Blue Strat

    Blue Strat Member

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    The GEs for $42 are a good bet. Oh yeah, the NOS Teslas (NOT JJs) are great at $30 a pop.

    If you need more info, email me. I won't be surfing the boards much today.
     

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