Which 12AX7 tube for my Trace head?

Discussion in 'Amps and Cabs [BG]' started by tomtrb, May 10, 2001.

  1. tomtrb


    Apr 17, 2001
    I need a 12AX7. Until recently, I did not know there were so many variables in tube types. I need something rugged, that can withstand sitting on my cabinet - vibrations, etc., and being dragged from gig to gig. I just want a nice fat sound, with clarity, good mids... I also would like a tube that has plenty of gain because my bass is a little weak. Maybe Im asking for too much. I just want the best tube I can get for my application. I appreciate any help from the experts.
  2. mikemulcahy


    Jun 13, 2000
    The Abyss
    I personally use either Sovtek or Grove tubes.
  3. ubersam


    Oct 12, 2000
    I've been suspecting that my preamp tube is starting to go bad. I'm not tube expert so I've been reading some of the old posts here re: preamp tubes and have done some research on the net. I've come up with a short list for myself of the ones that interests me.
    • Tungsram ECC83 ('ECC' = Euro designation for 12A*7)
    • Telefunken 12AX7
    • Sovtek 12AX7WA (supposedly the original preamp tube in Edens, 'WA' denotes ruggedized)
    • JAN Phillips ECG 12AX7WA (supposedly warmer sounding than the Sovtek but similar in tone, 'JAN' = Joint Army Navy, military spec'd)
    • Mullard ECC83 (supposedly has high gain and distorts fairly easily, maybe better suited for guitar amps like Marshall)
    • Mullard CV4004 (highly praised by guitarist, don't know how it would sound in bass amp application)
    I haven't tried any of these except maybe the Sovtek that's in my amp right now. I've also read that some have sustituted 5751 tubes in place of the 12AX7s and had liked it better, noting a tighter bass and cleaner sound. They also mentioned that the 5751s have lower gain, so if you like grit, it might not be able to deliver.
  4. engineer7


    May 11, 2001
    sounds like you are looking for a miracle tube! I would go with the a tube that will give you the sound you want, not the gain. maybe your bass is the problem and not the amp. also, i have done several tubes in amps in the past. Don't just stick a tube in and go to playing. Send it to a shop or somone experienced in electronics to install/bias/set the tube. Not doing so can damage the tube and/or the circuitry of your amp. It is a tricky job but a competent technician can perform that task. Hope that helps!

  5. Will the same tubes work in my new ADA MB-1?
  6. I use a Sylvania JAN 5751.
    A very long lasting tube with wonderful tone.
    they can be had for around $10, less then a 12AX7.
    You may want to check this site out for more information: www.audioasylum.com/audio/faq/joes-tubes.html
    Shouldn't be giving away my secrets.
  7. tomtrb


    Apr 17, 2001
    Thanks for the info,
    Im still researching but I think Ill go with a 12AX7 instead of a 5751. Probably Sovtek, or a JAN Phillips ECG 12AX7WA. A friend of mine knows how to service tube amps and he will install it for me. Hopefully Ill get my gain problem fixed with some modifications to my bass. Still looking for that miracle tube!
    Thanks again,
  8. Look for the "W" in an old USA tube (like 12AX7WA), 'cause that means it is ruggedized to withstand the shock from Naval gun blasts on a battleship. Seriously, that's what it means.