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Hartke 2000 Broken

Discussion in 'Amps and Cabs [BG]' started by endorka, Mar 20, 2005.


  1. endorka

    endorka

    Oct 15, 2004
    Glasgow, Scotland
    Hi folks,

    I have a broken old Hartke 2000 head, dating back to the mid 90's at earliest, which has been gathering dust for years in the cupboard. I suspect a power amp problem, the sound is always seriously distorted (totally overdriven sound) and quieter than one would expect from the settings. This happens irrespective of the preamp settings, and occurs with both tube and solid state preamps. Putting the EQ in and out also has no effect.

    Is this a common problem with these amplifiers? I'm considering getting the unit repaired, but not if it is going to cost a serious amount. Does anyone have any idea what the damage might be? I live in the UK, which could change things with access to spares and so on.

    Thanks for any help and advice on this,

    Jennifer
     
  2. BurningSkies

    BurningSkies CRAZY BALDHEAD

    Feb 20, 2005
    Seweracuse, NY
    I have a feeling it's not worth the $$$ to get this fixed. You could find a used 2000 for the price of a repair if it is the powersource...or if you're set on using a Hartke, you could find a used 3500 on the cheap or maybe find a Ashdown 300 in the same range.
     
  3. Unfortunately, it can be very difficult to troubleshoot a "sounds distorted" problem. Usually it's easier, in fact, to troubleshoot a "no sound at all" problem!

    So a shop could easily spend several hours or more trying to hunt down the problem, depending on the skill--or lack thereof--of the tech. And considering their repair rates, its true that it may cost more to diagnose and fix this amp than it's worth.

    Having said that, let's step back a little and see where the problem may be. You said it does it regardless of settings. However, have you listened to the signal from the DI out or from the preamp out? If this signal is clean, then the problem is indeed in the power amp section. If it's distorted, it's in the preamp section.

    Hopefully it's in the preamp section...if so, I'd try popping in a new tube (easy and cheap for you to do yourself). I have heard that a bad tube in these amps can cause both the tube and SS settings to sound distorted.
     
  4. Agreed. It might make a handy doorstop though. :bag:
     
  5. endorka

    endorka

    Oct 15, 2004
    Glasgow, Scotland
    Thanks for the replies guys, I have to confess to suspecting as much myself. I have been using an ancient 100W H&H amp instead of the Hartke for about eight years now, so long ago that I can't even remember what the Hartke sounds like! Given this, the need to have the Hartke fixed is not urgent.

    I thought about checking the preamp or DI output, but there are none of those on the amp! Perhaps these were only available on the 3500 model. I get exactly the same problems with the tube and sold state preamps, so I guess it is not the tube.

    Jennifer
     
  6. Sorry, I thought the 2000 had a preamp and DI out....

    Though it doesn't seem logical that a bad tube would affect both the tube and solid state sides, I have seen several people in this forum post that on their Hartkes, it did. So I would offer this advice: I'm almost positive the amp takes a 12AX7 which is one of the most common tubes on the planet. If you know any guitar player friends with a tube amp, they probably have one of these tubes in their amp. Take the cover off your amp, its just a few screws, and swap the tube with another good 12AX7 tube...hopefully, one borrowed from a friends amp. Just unplug the amp first!!

    This will give you a quick test just to rule out the tube. I'd hate to see an amp relegated to the scrap heap for a tube that costs $6 here in the US.
     
  7. BurningSkies

    BurningSkies CRAZY BALDHEAD

    Feb 20, 2005
    Seweracuse, NY
    Its entirely possible that the signal runs through the tube side of the pre wether you have it up or not. Lots of amps that claim a tube pre do this to get tube color, while it's not a 'true' preamp. The 2000,3500 and 5000 have pre knobs but no switching which would suggest that this is the case. A 12AX7 is cheap...like 6-10 bucks, and is a super easy thing to change out, even if you're like me and not nuts and bolts tech person...take the top off of the head, you'll see the tube (roughly behind the area of the preamp controls on the face panel. there's a little metal harness that is over the tip of the tube...slide it to the side and just unplug the ol' guy and put in the new guy. You can be in and out in less than 10 minutes.
     
  8. endorka

    endorka

    Oct 15, 2004
    Glasgow, Scotland
    Thanks again folks, that sounds totally logical, and definitely worth a go - I've lifted the valve out of the amp, which is showing its age... it is marked "MADE IN USSR". The photo of the same valve on a UK supplier's site is of course marked "MADE IN RUSSIA". They can be ordered for a few quid, so I'll get one ordered tomorrow and let you know how it goes.

    Jennifer
     
  9. Good luck! Hopefully, this takes care of the problem. If not, save those tubes--er, valves--because there's plenty of other amps that use them.

    While you're looking around in there, keep an eye out for any solder connections that look dodgy, or any parts that may appear "burnt"....
     
  10. tplyons

    tplyons

    Apr 6, 2003
    Madison, NJ
    And if none of that works, take out the tubes, grab a video camera and tape yourself throwing it out a window. I've always wanted to watch a bouncing Harke...
     
  11. Or you could fill it with concrete and use it for a boat anchor. That's a good plan for old computers too.:D
     
  12. endorka

    endorka

    Oct 15, 2004
    Glasgow, Scotland
    Hmm, I assume Hartke amps are not to everyone's liking...

    I've ordered the valve (tube!) so we'll hopefully soon find out the fate of the much maligned Hartke :)
     
  13.  
  14. endorka

    endorka

    Oct 15, 2004
    Glasgow, Scotland
    I honestly can't remember how the amp sounded, it has been so long since it was working properly. My only enduring Hartke memory is of Larry Hartke's mullet, which I believe he sported even in the 90's.

    If I can get this amp working I'll forgive him for the bad hair day.

    Jennifer
     
  15. BurningSkies

    BurningSkies CRAZY BALDHEAD

    Feb 20, 2005
    Seweracuse, NY
     
  16. endorka

    endorka

    Oct 15, 2004
    Glasgow, Scotland
    The valve arrived this morning, but alas made no difference when installed. No worries though, nothing ventured, nothing gained, and I have learned something in the meantime. Don't go sending the cement powder just yet though, I have been given the number of an apparently good local repair guy, so we'll see what happens.

    Thanks again for the help - much appreciated.

    Jennifer
     
  17. Too bad it didn't fix the problem, but as you said, it wasn't a huge expense. At least it was worth a try, and keep that new valve for your next amp!
     
  18. notanaggie

    notanaggie Guest

    Sep 30, 2003
    Actually, the symptom of "totally distorted and much quieter than expected" is potentially diagnosable......with ample room for error of course.

    Some Hartkes I think were made using MosFet outputs, but I think others were regular "bipolar" transistors. For sure I do not remember what model is which.

    With the regular type, that symptom often means that for one or another reason, the output transistors are not working, and only the driver transistors are delivering power. They don't get very loud.

    It varies from simple to parts-heavy as a repair, depending on cause.

    MosFets don't have a similar failure mode symptom, since they often don't have any driver transistors in the circuit.

    If you had said that it got "moderately loud", but was very distorted, I would suspect a failure of the "bias" circuit.

    With regular transistors, that usually shows up as a fuzz somewhat behind the sound, and you can still get pretty loud.

    With MosFets, it shows up as worse distortion, and loudness I would expect to be noticeably less, if you can stand listening to the distortion.

    Either way, the bias problem tends not to be as part-heavy a repair. You can get away cheaper.
     
  19. I had a Hartke 2000 and had this same exact problem. I destroyed the voice coil in an SWR 1x15 cabinet's speaker due to running that amp into the cabinet while it was broken, so be careful. I replaced the preamp tube and it didn't help. I ended up giving up on the amp... I'm pretty sure it had a bad solder joint or something like that. It's too bad, because it sounded ok at low volumes.
     
  20. Tash

    Tash

    Feb 13, 2005
    Bel Air Maryland
    Turn it into a l33t custom computer case.