New style Sovtek tubes

Discussion in 'Amps and Cabs [BG]' started by Caca de Kick, Dec 26, 2002.

  1. Caca de Kick

    Caca de Kick Supporting Member

    Nov 18, 2002
    Seattle / Tacoma
    I've been using Sovteks in both my Mesa 400's for years. Yup the ones in the red/wht/blu boxes.
    So it's time to get a new set and I run down to find a new Sovtek blu/wht box that says WXT on it.

    I get back to the jam pad and plug 'em in to find they sorta suck! Boy these new versions are real glassy...too much shrill and not enough beef. I don't like them.

    Has anyone else used them yet?
  2. Caca de Kick

    Caca de Kick Supporting Member

    Nov 18, 2002
    Seattle / Tacoma
    These aren't pre amp tubes I replaced, these new WXT's are power amp 5881/6L6 tubes. The boxes have a new look and new looked like they came out with a new variation since it said WXT on the box.
    All I can say is the sound is way too glassy on top.
  3. I have been using Svetlana 6L6GC for a couple years now in both my 400+ and they sound real smooth with just the right amount of grind. I didn't like 5881 tubes which are 6l6 military version (right PBG) they are more gritty and thin sounding. I like the fatboy sound...

    fyi: I use 12ax7eh pre tubes.

  4. bben


    Feb 28, 2002
    Santa Fe, NM

    As I understand the general wisdom, output tubes are good for 2000 to 3000 hours (except for the venerable 300B, which is good for about 10,000 but not used in guitar amps).

    All tube power amps should have adjustable bias, IMHO. I agree with psycho - shame on Mesa.
  5. Caca de Kick

    Caca de Kick Supporting Member

    Nov 18, 2002
    Seattle / Tacoma
    Wow, PBG! Incredible post! Thanks for all the info you packed in there. In all the years I've owned both of these Mesa 400 heads, only one other person mentioned I should have them converted to adjustable biasing, but he couldn't tell me why. Now I see why.

    Now I have to find someone in the area who can do it. I've seen a business card at a local shop of a 'tube guy' in the area. I'll print your post out and show him to see if he knows what I need.
    Don't worry about any factory warranty. One of the heads was built in '86, and the other in '88 (I've been playing both since 91/92), so there's no warranty anyway.

    I'll say, you nailed it...the difference was night and day, and as soon as I installed them I heard the difference instantly.
    January is going to be a very busy month for the band, and recording in early Febuary, so I better get on this asap to work on my sound.

    Thanks again!
  6. Hey PBG, I run 5881s in my 400+.. is it possible just to pop in 6L6 GCs? Are they interchangeable or do I have to install biaspots which I know you always recommend. (but if not then..?)

    With the term interchangeable, in this case, I mean substitute my mesa 5881s with mesa 6L6 GCs
  7. OK, thanks PBG! By the way will there be one, 6 or maybe 12 pots that have to be installed?
  8. Ok, so I need only two, thats nice. But when I measure the current dont I have to "cut the wire" or where/how is it measured? This is something I always have wondered about. Matched pairs is obviously the way to go. Thanks for your help, really appreciate it! :)
  9. Rockbobmel

    Rockbobmel Supporting Member

    Dear Psycho, I am planning to have a variable bias installed also. The problem is that my tech (In area) needs a step by step procedure. Would you be willing to provide this? Thanks,Bob
  10. If your tech doesn't know how to do this he probably shouldn't be attempting to rebias your amp, let alone modify the circuitry. Is there any chance you could find another tech in your area who is familiar with tubes?
  11. Rockbobmel

    Rockbobmel Supporting Member

    He may know quite well how it's done. I haven't talked with him yet. But you have hepled me out with specifics before, and I trust you more than anyone around here (or anywhere) about amps. I'll print this and give it to him to make SURE everything is done right. Thanks Again Friend:)
  12. jdombrow

    jdombrow Supporting Member

    Jan 16, 2002
    Colorado Springs, CO
    Also, keep in mind that many electronic components take a while to break in, so they may sound different after they have some hours on them. You might want to hook up a radio to your amp and let it play for a few days to get the tubes burned in.