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Tube suggestions?

Discussion in 'Amps and Cabs [BG]' started by klejst, Jan 24, 2013.

  1. I just purchased a Peavey T-Max amp off Guitar Center's website. It features a single tube (a 12AX7 I believe) in the tube pre-amp channel. I want to replace that tube so I know it is new and will have a lot of life (unless it is a dud) ahead of it. I read that pre-amp tubes last a long time. Therefore any suggestions to what brand to look into? This is my first time ever buying a tube.
  2. JJs are nice, but there's a whole world of tubes out there.

    Not sure how much of a tonal impact you'll have by changing it, but from a lifetime perspective, I'd just keep what's already there. They really do last a long long time!
  3. B-string

    B-string Supporting Member

  4. If it's only one pre tube, I'd look for a NOS GE 12AX7. They're pricey, but they're often thought to be the "best" for whatever that's worth. The NOS RCAs are good too.

    I have Svetlana Winged C powers in my SVT, but still have the original Magnavox pres so I can't speak to the Svetlana 12AX7 but the powers have been good to me for a few years.
  5. B-string

    B-string Supporting Member

    Just remember NOS means New Old Stock and no guarantee the NOS you buy is really an unused tube. That said, most used/still good old tubes will out-perform new production IME. Mullard, TungSol, Bugle Boy and Telefunken are very good old tubes as well as the standard RCA 7025 (industrial version of a 12AX7).
  6. deBont Amps

    deBont Amps Commercial User

    Apr 10, 2007
    deBont Amps
    I like Tung-Sol myself. Open clear tone.

    What kind of tone are you looking for exactly? There are a lot of awesome tubes out there, with just different characters.
  7. Mr. Foxen

    Mr. Foxen Commercial User

    Jul 24, 2009
    Bristol, UK
    Amp tinkerer at Ampstack
    It is pretty much a Fender type tone stack the valve is working in, need to bear that in mind when checking online valve comparisons, if they don't specify what sort of amp the valves are used in, renders the comparison a bit irrelevant.
  8. lowphatbass

    lowphatbass **** Supporting Member

    Feb 25, 2005
    west coast
    EH are known to be really durable. It's what Demeter told me to run in my 201 due the fact they mount horizontal which can be harder on the tubes. Honestly, I doubt you'll hear much difference between different tubes in that amp.
  9. Mr. Foxen

    Mr. Foxen Commercial User

    Jul 24, 2009
    Bristol, UK
    Amp tinkerer at Ampstack
    I've found Electro Harmonix valves to be about the most unreliable I've come across, in terms of starting fine and dying later, rather than being dead out the box.
  10. B-string

    B-string Supporting Member

    I'll second that fallowed by the NEW TungSols. IME
  11. bluestarbass


    Jul 31, 2007
    I believe today, all if not 95% of all tubes are made in the same factory in Russia. They are sold under different brand names. If it was just one 12ax7 I'd go with a nos jan tube. Jan tubes are several different brands, but they are durable and come from a good era of tubes.
  12. B-string

    B-string Supporting Member

    Not quite, there are several different factories. Sovtek does use a lot of different brand names.
  13. ThisBass


    Aug 29, 2012
    Start with one of standards like JJ or EH or sovetec or something else.

    Don't spend too much money in a lot of trials.

    If you don't feel happy with your tube path sound then call a technician. May be a technician can help cause he is able to modify the schematic of your tube stage.
  14. Floyd Eye

    Floyd Eye Inactive

    Feb 21, 2010
    St. Louis
    Personally, I don't care for any current production tubes, but I have also never seen an amp with one lowly 12AX7 in the pre where it even mattered tone wise. If it were me, I wouldn't spend any kind of money on it.
  15. SirMjac28

    SirMjac28 Patiently Waiting For The Next British Invasion

    Aug 25, 2010
    The Great Midwest
    I got into tube rolling last year and I have at least two of every tube B-String mentioned I put a NOS Black Plate mid 50's RCA tube in my Mesa combo it sounds nice but the difference in sound didn't justify the price with a single 12AX7 in a solid state amp you are not going to notice much sound difference between a $100.00 tube and a $10.00 tube there are even some great sounding Chinese tubes that are very inexpensive whatever new tube you put in there it will probably outlast the life of the amp and will have little effect on the overall sound.
  16. Mr. Foxen

    Mr. Foxen Commercial User

    Jul 24, 2009
    Bristol, UK
    Amp tinkerer at Ampstack
    If you ignore all of China and Europe and count all the former soviet bloc countries as Russia, then maybe.
  17. MontanaBassDude


    Sep 20, 2011
    I always have to imagine how many drunks sitting in the back of a room think to themselves, "Bummer, this bass guy WOULD have sounded great if only he'd change out his Mullard 12AX7 for a GE long plate."

    Never mind - I actually know the answer.
  18. JimmyM


    Apr 11, 2005
    Apopka, FL
    Endorsing: Ampeg Amps, EMG Pickups
    I have. JohnK did some tube rolling in his SVT 7 Pro and the JJ came off really bad and muffled while the Mullard he had made a considerable difference, and the other tubes he had (a couple basic NOS tubes and I believe a Sovtek) all sounded pretty similar...not quite as good as the Mullard but good and much better than the JJ.
  19. Floyd Eye

    Floyd Eye Inactive

    Feb 21, 2010
    St. Louis

    I believe it. I have never heard the Pro 7, but there's no doubt in my mind the NOS and especially the Mullard would sound better than a JJ or any current production tube. I have played several different SS amps with a single 12AX7 in the pre and none of them sounded like a tube amp to me, but as I said, I have never heard the 7.
  20. Thanks for the many inputs and suggestions. I may just open it up and see what tube it already has, but I can imagine simply changing one tube in the pre-amp is not necessarily going to make the amp sound like night and day, however mainly I was just implying that I don't know the actual age of the current tube. I know there is a lot of choices out there as far as brand goes so that is basically what I was asking input on, what brands to look into, which to stay away from etc.

    I don't have the money to invest in one of those sampler packs or to buy numerous tubes just to test, however I will say I usually play and prefer rock and punk type tone if that is how I can describe it. I have been looking online and found some 12ax7's that are labeled as pre-amp tubes and some that are just 12ax7's, because my tube is in the tube pre-amp channel of the amp am I limited to buying one that is labeled as a pre-amp tune or will pretty much any 12ax7 do the trick? Also for my amp can I just replace the tube or do I have to take it to a tech afterwards?

    Just doing some basic searching I found the JJ and Tung-sol 12ax7's going for around $15, the Mullard's going for close to $20, Sovtek's going for $10 and Mesa/Boogie's going for close to $18. At least on the sites I looked up they all got pretty good reviews, but I suppose it is personal preference at that point. Like I said it's my first time buying tube's so it's all new to me. Who knows maybe I really don't even need to replace the current tube yet. Anyone know ball park how long pre-amp tubes last?
  21. Primary

    Primary TB Assistant

    Here are some related products that TB members are talking about. Clicking on a product will take you to TB’s partner, Primary, where you can find links to TB discussions about these products.

    Feb 25, 2021

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