Discussion in 'Amps and Cabs [BG]' started by groovking, Sep 15, 2001.

  1. mullard 12ax7, ecc83, telefunken? i dont know, ..........i want a set of ballsy tubes for my 400+ and am considering mullard ecc83, which i think is an exact equivalent to 12ax7. is there a difference in the tubes along with the labeling of 12ax7, or ecc83, does it matter, are they exactly the same or is one more preferred?
  2. Tapp


    Aug 29, 2001
    USA, Mississippi
    Yeah ECC83 is the European designation for 12AX7; also you may see 7025 which is the same tube although back in the day of US tube production 7025's were supposedly lower noise. I would say use your ears and don't get caught up in the hype on different tube brands. Telefunkens are generally very nice and are highly regarded in the hifi world. Mullard's are as well and sound great too. I would also recommend the Sovtek 12AX7LPS and the EH 12AX7 for current production tubes. Also, be aware that not all of the "miniature" tube positions are the same tonally. Sorry I am not familiar with the topology of the new Mesa bass heads but I would bet a critical "tone" position would be the first stage preamp tube (or the 12AX7 farthest away from the power tubes).

    Let your ears decide most of all!! Those Mesa amps were primarily designed with Chinese (Mesa) tubes in mind and that may be the best option.
  3. ya, 1st position is most crucial. the socket closest to the guitar cable input. ive heard some good stuff about the EH preamp tubes. ive had no luck with the origional chinese output 6L6 s that come with the amp also. i trashed them and put a set of svetlanas in it and that made a big (HUGE)difference. ( the orig 6l6 s sounded like crap and rattled like a snare drum rattling ) . ......as far as preamp tubes. i had an older set of mb 12ax7 s which are in my amp currently now because the new preamp tubes i got from mesa sucked. highly microphonic, noisy and.....failures resulting in abnormal operation. ive had it with crappy preamp tubes! i did everything. i switched positions of my existing tubes. pulled some old tubes, and finally ended up with a mix of old and new tubes in the amp. (400+) i just cant believe what ive gone thru to get a descent sound out of it
    my mesa buster combos are particularly vulnerable to give problems with crap preamp tubes. the 400+ sounds good now but i just want a set of matched high quality tubes, so i can get the sound to be great. i even tried some nos jan phillips 12ax7wa s in the busters,........the problem with them is they whistle till they get warmed up, or should i say hot, then they still whistle some,.....like a tea pot,......i may have another problem in my buster combos but im not sure at this point. you definitly could not record with them as they are now. its very odd that two new units developed this symptom with very low hours on them..........i just got a set of telefinkens and im gonna try them in all the amps , but they are intended to go in the 400+. ive got a mullard coming that im gonna use , hopefully successful in the first gain stage of one the busters.

    CHRISTOS: IF YOU OUT THERE....are you experiencing any tea pot whistling, which is microphonics on your buster combo?
  4. VicDamone


    Jun 25, 2000
    There's an artical by Kurt Kurosawa in the volume 8 number 2 Bass Frontiers (Chuck Rainey cover).
    His top choices are:

    Sylvania JHS 5751
    GE JG-5751/5751WA
    Sylvania Gold Brand 5751
    Rca 5751