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Posts posted by psarkissian

  1. vpera,


    Sounds like a combination of a slight fret buzz and looks like a few burrs

    in the nut slots. Recommend getting the nut slots de-burred and the set-up

    checked and dialed-in just a little.


    Also recommend a Line 6 authorized person in your area with JTV experience.

    Yes, logging a ticket would be good.


    Reminders- register the product, log a ticket, use a Line 6 authorized service center.

    Things go so much more smoothly and efficient that way for you.

  2. Have your local Line 6 authorized service center that does guitars have a look at it,

    it may just be a set-up or alignment issue.


    Set-ups are checked at the main distribution point. However climate at a given location

    can have an effect on the set-up. Since they don't know where a guitar is going to at that

    point, the set-up would be done to the specifications and not the location of the end destination.


    However, when I do repair or service a guitar, I adjust the set-ups for the end destinations.

    Sometimes it's needed that the local tech may need to dial it in that last smidgeon.


    When a guitar arrives, it's good to play it and give the set-up 2-4 days to acclimate to the

    end destination where you're at. Then, if needed, go to a local guitar tech for that last final

    smidgeon of adjustment.


    2013 necks have the most recent current neck specs.

  3. Listening to the audio clip, sounds like either the processor

    clock is failing or an input amp is failing on the UX2.


    Very slim chance,.... your computer is 64-bit, the UX2 is 24-bit,...

    I take it your sound-card is doing internal conversions.


    I asked about the mic earlier, because too many people use

    dynamic mics on these, and so they blow the phantom power

    line as a result. At least you know to use a condenser mic,... very good.

  4. Use the recommended cable and cable length.

    Line 6 link cable and mic cable are not the same.

    Impedance are different and the uses are different.


    AES/EBU,... it's the standard issue for this sort of application.

    For the uninitiated,... AES being the Audio Engineering Society,

    and EBU as in the European Broadcast Union.

    • Upvote 1
  5. The Sovtek 5881WXT is what Rheinhold Bogner spec'd for this one (Spider Valve series).

    The Sovtek 5881/6L6 WGC doesn't have the cup at the bottom which created problems with tube retainers

    so we don't use those anymore.


    People want the crunch of a Mesa tube, unfortunately too many with Mesa tubes come back with problems.

    JJ's and GT's also come back to us with problems, and things like the bias being way off-spec.


    The Sovtek 5881WXT is what Rheinhold Bogner spec'd for this one (Spider Valve series). There are interactions

    between the digital portion and the tube portion, such that, it is not as forgiving as old 60's as 70's tube amps.

    You can't get away with the same deviations with these as we used to with older tube amps.



    We have our tubes go through some extra scrutiny.

    Best to stick with the specified tubes,... less problems that way.

  6. No, I'm not new,... the thread is out-of-date. I'll let Dave know, thanks.

    I've been dealing with Spider Valve since the beginning, been dealing

    with tubes and tube amps for more than four decades.


    The characteristics curves of the JJ's, Mesa's and Groove Tubes

    are not close enough. If those are biased the same to the

    bias settings for the 5881WXT's,... then the amp ends up on

    my bench with problems. Can't use the same bias settings on these

    other tubes as with the 5881WXT.


    I see too many come back because of the wrong tube and/or bias settings.

    This is a mixed technology amp. You can't get away with the same

    sort of things we used to get away with for Marshall amps with 6550's

    in them.


    These amps are not as forgiving as the tube amps of yesterday-years.

    It's a Bogner hot-rod.

  7. Be sure to use the correct impedance output for the cabinet that you are using.

    They have to be matched or the tubes and circuitry will get stressed,... and then

    it will end up on a technician's bench. And that's no fun.


    Keep your fingers out of the inside of the amp,... even with the power off, a capacitor

    can discharge into your hand, and that hurts like hell.

  8. "I was just wondering if the "two tubes out" solution would work as a temporary

    solution in case I could not get it done before the upcoming gig." ----



    Don't do that.


    These aren't our grandfather's tube amps, these are mixed technology amps,

    you can't get away with this sort of thing like we used to in the old days. They

    are not designed to do that.

  9. It may be only that it's time for a tube change out and bias. Good idea to do that once every

    12-18 months if you're a performing musician. Have it checked out at a Line 6 authorized service

    center in your area, that knows tube amps.


    Sales person should have never pulled two tubes out of it,...  much less the wrong two tubes. It

    offset the push-pull symmetry. That and how long they've been in the amp is probably why the

    one tube was hot.


    Don't try to deal with it yourself, it hurts when you get zapped. Take it in to a service center, have

    the right tubes put in and biased by a tech.

  10. Tube amps should be dealt with by a Line 6 authorized service center.

    They will have access to service manual and service info. There's more

    to the bias procedure than adjusting a trim pot. Specified tubes should

    be used.


    I see too many amps come across my bench because someone tried to

    hot-rod an amp that's already hot-rod. It's a hybrid amp with a digital section

    and with multiple gain loops and amp classes. Using non-spec tubes will

    create problems. Using incorrect bias will create problems, bias is not a

    "one size fits all" proposition.


    These aren't our grandfather's Marshall or Phase Linear tube amps.

    Leave it to the guys with the service info access. Besides,... it really hurts

    when you touch the wrong thing and get zapped!

  11. That and other things.

    As for what's on the board,... can't get into that.


    Klystron is a special kind of tube used for power amp outputs at

    hi wattage commercial radio stations. Also used in microwave communications.


    Oh, and,...  in certain situations the oil can are used as coolant for the tube.


  12. For guitar amps, Bogner knows how to deal with it, he's good at it.

    Audiophile tube amps are another beast and specially all their own.

    And there are techs like me who deal with both,... and radio station transmitters as well.


  13. If you were to take transparencies of the characteristic curves of the the different

    brands of EL34's and EL84's, and overlay them, the linear regions of the transfer

    may line up, but it's the where and how non-linear regions of the curves differ that

    will create the problems.


    I've built my share of tube amps, I've been servicing tube amps for decades. No voodoo,

    no lollipop,... it's just plain physics of electronics.

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