Question about filter caps....

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by mcdes, Feb 7, 2012.

  1. mcdes

    mcdes Member of no importance

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    Been doing some reading up about my heritage vox, and looking at uograding some parts. At this stage probably like for like if i can.

    Say I had 47uF/350v caps..... If I got ones with a higher voltage, ie, 47uF/500v, is that bad? What difference will it make?

    If someone can enlighten me if the the voltage matters, or wether its a max rating?

    Also in the caps, for 100k nF? is that .1, .01 or .001?? My guess is .1 but I wanna check first.

    Thanks in advance.



    Ps, yes yes, lethal voltages, be careful. Thanks
     
  2. VacuumVoodoo

    VacuumVoodoo Member

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    Voltage rating tells you how high applied voltage the capacitor can withstand.
    You can always use higher rated capacitor to replace a lower rated one but not the other way round.

    "100k" cap: k=1000pF, do the rest of conversion to uF :)
     
  3. guitarcapo

    guitarcapo Senior Member

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    I've heard that higher voltage rated caps last longer, so you should go with a higher rated cap if space
    and cost considerations allow it. Another feature to look for is the temperature rating. The higher the better.
     
  4. mcdes

    mcdes Member of no importance

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    Great thanks guys!
     
  5. Billm

    Billm Member

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    Yes, I've seen this in practice. In the first generation of Blues Juniors, Fender used 500 volt caps, even though the B+ was around 330V. They switched to 450V caps from the same vendor. I never see bad 500V caps, even though they're the oldest, and they always seem to have good, low ESR numbers. I replace a fair number of newer 450V caps.
     
  6. mcdes

    mcdes Member of no importance

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    yea, mine have 350v ones, so ill change them to F&T 500v
     
  7. GearHeadFred

    GearHeadFred Member

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    The temp rating is something to consider as well, as these things tend to "cook" in guitar amps.
     

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