Doing some repairs to my old Laney AOR30...capacitor questions

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by Pott, Aug 11, 2008.

  1. Pott

    Pott Member

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    Hey y'all...

    I just got my old Laney back yesterday, and having ordered the proper filter cap ages ago, replaced it. But of course I figured I may as well replace all the big electrolytics (only ones I can replace without access to the underside of the PCB, the whole board is basically stuck in place and I don't have the expertise, time and patience to unwire everything, replace all the caps, rewire everything as it was etc...)
    Here are some pics:
    [​IMG]
    I'm guessing the dark smudge on this 15uf 450V is a leak? The main filter cap was also leaked but I knew this from multimeter reading (right after the amp was off, it held only about 20V instead of over 250...)

    So I want to replace all of these caps but Maplin don't carry them. Where do you guys think I could get the best for that job?

    Here are some more guts pron:
    [​IMG]
    [​IMG]

    Thanks!


    Hotrox here in the UK carries 16uf caps with a 475V tolerance. Would that 1uf difference be a problem or can I safely replace these 4 big caps with them?
     
  2. OlAndrew

    OlAndrew Member

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    A 1 uf dif is well within the normal +/- tolerance for these kind of things. The xtra voltage tolerance is a good thing. you can go double the uf's on most of these power supplies without problems, and some people do in an attempt to eliminate hum. That's on the plate B+ to the power tubes, and maybe the screen grids....oversize caps on the preamp supplies can affect tone.
     
  3. Pott

    Pott Member

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    These caps go between power supplies and the preamp valves. Worse to come, I lose a little noise it seems, so I think I'll go for it then :p Thanks!
     
  4. OlAndrew

    OlAndrew Member

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    A 1 uf change won't make any discernible difference in anything. Some guys will double the stock size, or more. Now THAT makes a change.
     
  5. Pott

    Pott Member

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    Great thanks!
    They're £4 a piece though so I may wait a little or try ebay first. Yikes...
     
  6. mockoman

    mockoman Member

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    I think John Phillips is in your area. He is a very knowledgable tech; you could look him up if you need help.
     
  7. Pott

    Pott Member

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    Aye he is, haven't heard from him in a while, I'll see what he's up to. I don't want to bother anyone as far as I can do the work myself. Ordered the caps today!
     

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