Post-amp repair - ghost notes/undernotes! Tube amps keep screwing me over...

Discussion in 'Gear & Equipment' started by guitar4tw, Apr 13, 2010.

  1. guitar4tw

    guitar4tw SS.org Regular

    Messages:
    767
    Likes Received:
    194
    Joined:
    Nov 26, 2009
    Location:
    Norway
    My Invader recently blew a tube. I played, there came a loud pop, then a lot of fizzling and crackling before the volume disappeared completely. I promptly turned it off .

    I was afraid that the amp would have been damaged somehow and that even a fresh tube swap wouldn't get the old tone back. The reason for this is my friend experienced this exact thing not too long ago. His amp blew a tube, and he had a tech install a set of fresh new tubes of the same brand. Biased correctly and everything was supposed to be good to go. Except it wasn't... His old tone was gone and the tone he had now was much more trebly and fizzy. Not a huge difference in tone (it wasn't fubar), but definitely not the same. He got yet another identical set of tubes installed, but yet again the tone was crappy.

    So back to my story. I got my invader back from my tech (who is really good, btw). I had him install a set of =C= power tubes, so they are a little bit different than the stock tubes (which are Sovtek), so I expect a minute difference in tone. Now, the tone is okay and not too different (I attribute the little difference there is to the new tubes), but there are now "ghost notes" or undernotes to the notes I play. They stick out most on the D and G string above the 12'th fret, but they are audible everywhere.

    A ghost note is basically a tone that follows what you play in what sounds like about an octave below (though not the same key). It's very quiet, so I didn't notice it at first when I switched on the amp. It's definitely there, though, and now that I know it's there it's all I can hear when I play. My ears get fixated towards it.

    Imagine it as a slight humming sound, folowing the keys you play at any given moment in a note somewhere below. It's only audible when playing single notes on one string...

    -----

    So if you've stuck with me through that wall of text, you deserve a cookie. Now here comes the question: What the hell is wrong now? I've done some googling, and it appears that most people confuse ghost notes with "cone cry" from the speakers. This is not that, as I play through the same cabinet as before. A ghost note isn't erratic and mechanical sounding like that, it's basically a hum that is created within the amp.

    I read that it is often a sign of bad caps. Could a cap have gotten bad from the power tubes going?

    Something is not right, and I am getting damn tired of tube amps right about now. 2 years of Mesa problems, and after two months this Invader has been at a tech twice because of bullshit. I just want to get back to playing and enjoying guitar, and not worry about whether or not my gear sounds right. :realmad:

    So before I take it down to my tech for the third time, are there anyone here who have any ideas?
     
  2. PirateMetalTroy

    PirateMetalTroy The Tooth Fairy

    Messages:
    1,248
    Likes Received:
    365
    Joined:
    Apr 9, 2008
    Location:
    London, ON (Canada)
    Sounds kinda like you're describing cone cry. Or maybe you've got a microphonic tube in there.
     
  3. guitar4tw

    guitar4tw SS.org Regular

    Messages:
    767
    Likes Received:
    194
    Joined:
    Nov 26, 2009
    Location:
    Norway
    I'm 99.9% sure it's not cone-cry, as it didn't appear before the tubes blew. I also thought cone-cry happened at very high volumes, where as this is present even at a really low volume.

    The pre-amps are not microphonic, I've tried tapping them. :/
     
  4. PirateMetalTroy

    PirateMetalTroy The Tooth Fairy

    Messages:
    1,248
    Likes Received:
    365
    Joined:
    Apr 9, 2008
    Location:
    London, ON (Canada)
    can you post a sound clip? Any chance it's trem springs or something like that?

    try moving your head off your cab to the floor and see if that changes anything.
     
  5. guitar4tw

    guitar4tw SS.org Regular

    Messages:
    767
    Likes Received:
    194
    Joined:
    Nov 26, 2009
    Location:
    Norway
    I could try to record a clip with my crappy skype mic, but I doubt you would be able to hear it. The sound quality is too poor. It's not trem-springs, or other parts on the guitar, either. :/

    I guess I'll just drag the 55 pound crapbox down to my tech for a third time and let him troubleshoot it. It's almost funny how many times I've walked through that door with an amp that needs repairing... As he says, tube amps must hate me. XD
     
  6. eaeolian

    eaeolian Pictures of guitars I don't even own anymore! Super Moderator

    Messages:
    13,412
    Likes Received:
    765
    Joined:
    Jul 21, 2005
    Location:
    Woodbridge, VA
    It's possible the phase inverter tube is bad, too, as that sometimes can cause the type of thing you're describing. Does Engl have anything to say on the subject?
     
  7. JJ Rodriguez

    JJ Rodriguez Contributor

    Messages:
    14,738
    Likes Received:
    1,350
    Joined:
    Aug 16, 2005
    Location:
    Fredericton, New Brunswick, Canada
    I'd say :lol: Especially if you had Mesa's crap out on you, as well as your Engl.

    Mesa's are fucking tanks from everything I hear, and I doubt the Engl is poorly made. Are you plugging into a power conditioner? Maybe you have shitty power in your home and it's frying your shit.
     
  8. guitar4tw

    guitar4tw SS.org Regular

    Messages:
    767
    Likes Received:
    194
    Joined:
    Nov 26, 2009
    Location:
    Norway
    I've sent them a mail and waiting for a response. I'll report what they say :)

    The wiring and all power in the house is pretty new, actually, and I run the amp through a Monster current cleaner station, so the power should be great. :)

    And yeah, both Mesa and ENGL should be well built amps, but I've had them both crap out on me. The mesa had a problem with the inbuilt power supply (or something similar, can't remember), then there was something wrong with the ammount of current the tubes received (it was erratic or something, I think a bad cap was the problem), and then something else weird happened to it after I had sold it (and I payed the repair, again). This one has had a bad pre-amp tube, blown power tube, and now this crap. :noplease:
     
  9. budda

    budda Guiterrorizer Contributor

    Messages:
    21,164
    Likes Received:
    1,353
    Joined:
    Jan 22, 2007
    Location:
    London ONT
    Your friend's tone became more trebley and fizzy because a) he didn't turn the treble back down :lol: and b) when power tubes start to get older, you lose your highs/note definition.
     
  10. Enselmis

    Enselmis SS.org Regular

    Messages:
    1,189
    Likes Received:
    41
    Joined:
    Jan 23, 2010
    Location:
    Winnipeg
    Wait, so you blew a tube after 2 months..? Damn...

    Do you play, like, REALLY FUCKING LOUD?
     
  11. MaxOfMetal

    MaxOfMetal Likes trem wankery. Super Moderator

    Messages:
    25,904
    Likes Received:
    2,737
    Joined:
    Aug 7, 2008
    Location:
    Milwaukee, WI
    That has little to do with tube life. :lol:
     
  12. Chickenhawk

    Chickenhawk Monolithic A.D.-dibs Contributor

    Messages:
    4,098
    Likes Received:
    647
    Joined:
    Jan 13, 2010
    Location:
    Misery
    I played a Triple Rec for a while, and every hour (no...fucking..shit) it would blow a fuse.

    Was sent to a tech a dozen times (again, no shit), and they could never find out what was wrong. Even went to Mesa, and they said nothing was wrong. But, no matter where at (gigs, my house, my other guitarist house, the rehearsal spot, the studio), every hour it would blow a fuse.


    back on topic.

    check the phase inverter tube, and re-check the tubes to see if their microphonic. Maybe you missed it the first time :scratch:
     
  13. guitar4tw

    guitar4tw SS.org Regular

    Messages:
    767
    Likes Received:
    194
    Joined:
    Nov 26, 2009
    Location:
    Norway
    Thanks for the help guys. I think it MIGHT be a bad cap, so I'll let my tech look at that today. It seems that a bad power filter cap will produce a ghost note like this, so let's hope it's something obvious that can be fixed.
     
  14. JJ Rodriguez

    JJ Rodriguez Contributor

    Messages:
    14,738
    Likes Received:
    1,350
    Joined:
    Aug 16, 2005
    Location:
    Fredericton, New Brunswick, Canada
    CentaurPorn on here had a Mark IV and it never once blew a fuse or had a tube die in the months he had it, your story sounds like an exception to me. I've heard of people dropping their Triples from several feet high onto pavement, replacing the tubes because they shattered, and rocking out like nothing happened :lol: Sounds like you just got a lemon.
     
  15. cyril v

    cyril v Contributor

    Messages:
    2,749
    Likes Received:
    318
    Joined:
    Sep 5, 2007
    Location:
    New Jersey
    Damn, I would've just checked it myself to see if it was bad caps... they are easy as hell to spot and are also probably the easiest solder job someone could possibly do IMO. A few of them blew in my hdtv and it took me longer to find and purchase the caps while inside radioshack, than it did for me to physically replace them.
     
  16. guitar4tw

    guitar4tw SS.org Regular

    Messages:
    767
    Likes Received:
    194
    Joined:
    Nov 26, 2009
    Location:
    Norway
    Went down there today and it turns out there is something wrong with the power section of the amp. Something about the power supply/caps or something. My tech said that he would need some parts that he doesn't currently have, and told me the best thing to do would be to send it to ENGL in Germany under warranty and let them do a thorough fix.

    So, this couldn't have happened at a worse time. Because of the god damn volcano in Iceland, no planes are flying, so it might have to be shipped by sea. Hurray...
     
  17. JJ Rodriguez

    JJ Rodriguez Contributor

    Messages:
    14,738
    Likes Received:
    1,350
    Joined:
    Aug 16, 2005
    Location:
    Fredericton, New Brunswick, Canada
  18. guitar4tw

    guitar4tw SS.org Regular

    Messages:
    767
    Likes Received:
    194
    Joined:
    Nov 26, 2009
    Location:
    Norway
    Luckily my tech is a super nice guy and offered that the store could borrow me an amp that I could use in the meantime. Still, this sucks.

    I payed the equivalent of about 4500$ for this thing, and this is the third problem in just over 2 months. This could be the reason that the pre and power tubes blew, though.
     
  19. Nights_Blood

    Nights_Blood Fire and Brimstone

    Messages:
    594
    Likes Received:
    61
    Joined:
    Jan 5, 2010
    Location:
    SoCal
    Wow, man. That is some horrible luck. Maybe these are signs telling you to get an axe fx.
     
  20. guitar4tw

    guitar4tw SS.org Regular

    Messages:
    767
    Likes Received:
    194
    Joined:
    Nov 26, 2009
    Location:
    Norway
    Yup, I'll most likely fix it, sell it and get the axe-fx ultra with the Carvin ts-100e power-amp.
     

Share This Page