GK 400rb-III problem... please help!

Discussion in 'Amps and Cabs [BG]' started by bass349, Nov 3, 2004.

  1. hi all,

    i have had my Gallien Krueger 400rb III (2x10 combo amp) for a few years with no problems whatsoever. i mainly use it as a practice amp and haven't really gigged that much with it.

    a few days ago while i was praciticing it just went all quiet. i mean, i could still hear a little bit of sound coming from the speakers, but really really quiet, more like a buzz. at first i thought the battery was gone in my bass, but i checked it - all good, and also checked it with my spare bass. then i turned the volume to full on my amp (which i never do, way too loud!) touched the strings and the amp went BANG. i turned the volume back down and my amp was working again fine :confused: it has since happened a few times again, totally randomly, and i have *fixed* it both times by cranking the volume until it 'pops'.

    i'm hoping it's an easy fix. i really can't afford big repairs at the moment :rolleyes: does anybody know what this is/had this problem before?

    any help would be greatly appreciated,
  2. I'm not an amp tech, but my best guess is that you have a bad connection somewhere in the amp. If you keep going "BANG" to fix it, you may wind up doing more damage. I'd talk to a repairman if I were you.
    You don't want an amp you can't rely on and it's not going to fix itself. :/
  3. hmmmm.... yeah i just dropped it off for repairs today. the guy said that it may be a problem with the speakers... whatever the case he said it should be fixed by next week unless he has to order parts in, so i'm happy as long as he doesn't charge an arm and a leg :smug:

  4. Good luck with it, hope it's just a minor problem like a cold solder joint or something like that.
    Post again when you get it fixed so we know what was causing the problem.
  5. Eric Moesle

    Eric Moesle Supporting Member

    Sep 21, 2001
    Columbus OH
    My guess (and it IS just a guess) is a loose solder joint. If it is, lucky you, its a quick and cheap fix.

    Best of luck!
  6. ihixulu

    ihixulu Supporting Member

    Mar 31, 2000
    getting warmer
    Could it be a dirty pot? I've had several pieces of gear exhibit that type of behavior and in most cases cleaning the pots with Deoxit took care of it.
  7. hey guys,

    yeah, im hoping it's just a solder joint! thanks for the replies, i'll let you know when i get it back...

  8. I know this thread is a couple of years old. Different place and person, but I'm having exactly the same problem with the same kind of head. It gets very light use. The problem was intermittent but now seems to have become permanent. What did that turn out to be? Has anyone else had this? I love the amp when it's working. I play it through an Aguilar 112 and it sounds great.


  9. metalguy2


    Dec 26, 2004
    I am having the same problem.. I wish someone posted the remedy.
  10. Got no responses, so I did some basic stuff. I bought a can of contact cleaner at Radio Shack (~$10) . I took the top off the amp. (unplugged from power, of course). I could not see any obviously loose or fragile connections. Actually had to replace the power supply fuse, which blew at one point (amp went completely dead after that). (I guess its possible that a really old fuse may have been contributing to the problem? not sure...). At any rate, using the red tube that comes with the contact cleaner, I sprayed quite a bit of cleaner into every pot, switch, and input or output jack inside the amp. I then proceeded to spend 15 minutes or so rotating every knob as far as it would go. (I should have also taken a guitar cord and repeatedly plugged it into every jack while wet with cleaner.) Then I put it back together, and so far it is working fine. Big relief!!! I had a little relapse when I plugged my tuner into the tuner jack, probably because I did not spend enough time cleaning the jacks. This is all basically amp maintenance 101, I can't promise it will work for you. I'm also not sure if this would void warranties or anything. I think a serviceman would start by doing this same cleaning process.

    Good luck - I'd still be interested in hearing if people have had other experiences.