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i think my IOD is toast!

Discussion in 'Amps and Cabs [BG]' started by jasonbraatz, Feb 6, 2002.


  1. jasonbraatz

    jasonbraatz

    Oct 18, 2000
    Oakland, CA
    it, along with the rest of the contents of my rack, fell about 3 feet onto a concrete floor.

    now if you turn up the "drive" knob, it gets quieter, even with the blend all the way on "direct."


    i'm gonna crack it open to see if something obvious happened, and swap out the tubes for my old ones (i JUST put a full set of Ei's in there a week ago :( )


    making things worse - i had to play a gig today after it happened but i hadn't played it since it fell, so i didn't know if it was broken or not. so if it was the tubes that are toast - could more stuff be toast now? what and how should i check to see if stuff is broken (i'm confident using test equipment and soldering - i biased this thing twice already and i'm still alive :) )


    first my speaker cab needing reconing, now this.


    suck.



    jason
     
  2. Angus

    Angus Supporting Member

    Apr 16, 2000
    Palo Alto, CA
    Wow, no good! Sorry to hear it...I just finished playing around with my working IOD, so I really feel your pain!

    How'd it fall? Must've taken a good nudge to knock over a big heavy rack.

    There's really no way of knowing if the gig could've damaged the equipment more without knowing WHAT is screwed up. Possibly, if the tubes were cracked or something, then it fried them some more, which really doesn't matter anyway! Whether the gig made it worse or not is moot, as long as you find out what's wrong with it.

    Is only the IOD broken?
     
  3. jasonbraatz

    jasonbraatz

    Oct 18, 2000
    Oakland, CA
    yeah - big props to the carvin DCM1000, it's as good as new.



    and actually, my dumbass brother loaded onto the cart poorly as we were loading out from a gig, and he hit a door or something backing it out and it fell off the back.



    i think after i get all this **** fixed i'm going to get a clarus and a 6 space rack. the clarus so i don't have to lug the rack everywhere, and the 6 space so it doesn't move around so easily.


    too much homework tonite, i'm gonna crack her open tomorrow and poke around :(

    jason
     
  4. Since you've been inside already, get your VOM out and do some basic voltage checks. Look at the +250V coming off the standby switch that feeds all the tubes. Rebias the EL74 and check the 12AX7 too. Many of the jacks in the IOD are the switching type, inspect those also.

    You are dealing with physical damage here: something loose or disconnected. Be sure to check the 8 ohm resistor and the switching jack to the Speaker Out.

    Reseat all three tubes. Power up and see if the heaters work, etc. Swap in your old EL84 pair (I assume you kept them!) and the old 12AX7.
     
  5. Tapp

    Tapp

    Aug 29, 2001
    USA, Mississippi
    Jason, I would go ahead and swap all 3 tubes to start. After you've done this check some voltages as Bgavin says and check your bias, then with the bass plugged in I would get a sharpie marker (or something non-conductive) and poke around the circuit board and listen for cracks and pops. You will probably hear little stuff as you probe the grids and plates but you shouldn't hear a big crackle. This is a good way to see if you've got something that's come loose. Of course don't turn up the volume very loud; I wouldn't want you to blow a speaker in the process.

    Let us know how it goes

    Tapp
     
  6. jasonbraatz

    jasonbraatz

    Oct 18, 2000
    Oakland, CA
    pulled the tubes and swapped with ones that weren't in the fall - one of my EL84s had a rattle so i thought that would do it.


    still broke.


    checked bias, plate voltage, and lots of other voltages and everything seemed ok.

    poked around with a pen and nothing moves or is loose.


    i think i'm ****ed.


    :( :( :(


    jason
     
  7. jasonbraatz

    jasonbraatz

    Oct 18, 2000
    Oakland, CA
    and - to make matters worse, i just pulled the grille off my goliath jr, pushed in on one of the speakers and sure enough, there was a distinct grinding sound.



    :(
     
  8. Tapp

    Tapp

    Aug 29, 2001
    USA, Mississippi
    Sorry to hear it man, Is it still under warranty? I would call SWR and maybe if you catch them on a "good day" they may take care of it for you. I would definitely call them at this point. Since the unit was racked and all of your other rack items still work fine it should be functional too (minus a possible tube break).

    Tapp
     
  9. That really sucks, I'm sorry to hear that man... You sounded like you were in love with that preamp too. Try checking out the Grand prix as a replacement, I tried one out the other day and was very impressed.

    Good luck anyways.