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HARTKE Distortion from HF outputs??????

Discussion in 'Amps and Cabs [BG]' started by aniki, Sep 5, 2005.

  1. aniki


    Aug 12, 2005
    Hi All,
    Despite searching the database on here, I couldnt find anything that describes my problem exactly. :bawl:
    My Hartke 5000 has a fault whereby the button on the rear to switch from bi-amp to mono appears to have no effect.
    Either way the crossover control is still active.
    This led me to discover that essentially the HF output jacks are outpuitting a distorted signal, whereas the LF output jacks are perfect.
    I have tried switching cabs to check consistency to my theory and its defo the amp!
    Any ideas whats up & if its fixable would be greatly appreciated.
    Thanks in advance for any pointers :bassist:
  2. aniki


    Aug 12, 2005
    I'm gonna replace the tube anyway as Ive never done it, but as the distortion is only on the HF outputs, am I correct in assuming that the Tube cannot be the cause of the problem?
  3. BillyB_from_LZ

    BillyB_from_LZ Supporting Member

    Sep 7, 2000
    Sounds like a potential problem with the power amp on the HF side.

    If you need a schematic you can get one for free from Hartke or send me an email and I'll send it to you.
  4. Hartke didn't send me one even though I asked them....

    if you've got one, I'd sure appreciate it!! so I'll drop you a PM....
  5. Mine's 8 years old and I've noticed an occassional difficulty with dirty pots and switches. Though I haven't gotten around to spraying them yet....I've noticed some rough sounds when the graphic EQ was switched on, but after cycling the switch a few times things were OK. Did you try cycling your mono/biamp switch a few times?
  6. aniki


    Aug 12, 2005
    Hi people, thanks for your replies.
    Well, to be honest I'm not techy enough to really know too much about whats going on inside. I cant say that Ive fixed the problem but so far so good :cool:
    Faced with the option of leaving it at the repair shop for a week or more I just had to try one last resort.
    I basically took the lid off, removed the tube and re-seated it (although this will be replaced tomorrow).
    I then removed about a mug-full of DUST using a mini keyboard vacuum/brush. With attention to the earthing points and anywhere it had 'accumulated'.
    Lid back on, powered up.
    First of all I noticed the fan was quieter and I could even feel cool air blowing through the active input socket!
    Moved the balance control to high freq, first tell tale pluck and :hyper: :hyper: all is good!
    Tried cycling the mono/biamp switch a few times and although I still believe there could be a fault (as in it doesnt disable the crossover control completely), the HF outputs are as they should be.
    My main concern was that only using the LF outputs I may not be getting full power??
    Now I can have my 2x10 in the HF and 1x15 in the LF and adjust the balance accordingly without the background 'farting'.
    Cheers for your help guys. At least now I can (hopefully) get through the next month of gigs and then maybe get it checked properly when I have a little more time to spare :bassist:
  7. Glad it's working better! A cup of dust is a LOT of dust.

    For full power, both amps must be working, since this is actually 2 separate 250 watt amps. If only one set of outputs is working, that's only 250 watts.

    Sure wish Hartke had made this capable of bridge mode....

    In Mono mode, the Frequency knob doesn't do anything on mine, but the balance will shift from one set of speakers to the other.