The effect (if any,) of using overrated coupling caps.

Discussion in 'Amps/Cabs Tech Corner: Amplifier, Cab & Speakers' started by HandOfTheHost, Jan 29, 2008.

  1. HandOfTheHost

    HandOfTheHost Member

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    I've heard that it's okay to use correct value capacitors that have a voltage rating greater than called for. Tonally speaking are there any drawbacks to doing so? I don't think there should be, but I'm not sure. Thanks.
     
  2. WaltC

    WaltC Member

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    Most of the coupling caps I've seen (and used) over the years (e.g. Mallorys, OD Spragues, other Spragues, etc.) have been rated for 600 volts and are used from the preamp section (200 volts or so most times) to the PI and finals (400+ volts) with good success. I've even used some Sprague ODs rated at 1000V without noticing a difference more than the difference you hear between *any* two supposedly equal caps.

    Beyond that I don't have any experience or opinion <G>.
     
  3. HandOfTheHost

    HandOfTheHost Member

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  4. HandOfTheHost

    HandOfTheHost Member

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    I want to hear for myself the difference between the stock, doo-doo brown caps in my Bassman and replacements, so I've ordered some Russian paper-in-oil. There were 630 volt ones and 1000 volt ones. I ended up getting the 630v's as they are closer to spec.
     
  5. booj

    booj Member

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    The size is probably the only real difference you'd notice.
     
  6. JacksonAmpworks

    JacksonAmpworks Member

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    I hate to be a realist, but the only thing you will notice is they are larger and more expensive. :)
     
  7. hasserl

    hasserl Member

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    +1 :AOK
     
  8. HandOfTheHost

    HandOfTheHost Member

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    Fair enough, but you won't use just any cheap, generic capacitors in your amps do you? Very nice looking amps btw. As I understand it, everything makes a difference in varying degrees, so I'm trying it.
     
  9. brad347

    brad347 Member

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    lots of people believe that caps don't make much difference because it doesn't show up on a spectrum analysis.

    But phase anomalies and non-linearities do not show up on a spectrum analysis. No capacitor is perfect and they all have some inductance and phase shift which is different at different frequencies.

    I bet you notice a change with the paper-in-oil caps if you are replacing every cap in the amp. Make sure to let them break in for awhile. In my humble experience, the sound of caps tends to change after the first few dozen hours.
     
  10. HandOfTheHost

    HandOfTheHost Member

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    That's what I'm planning, changing all of them.
     
  11. JacksonAmpworks

    JacksonAmpworks Member

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    You are right! There is a difference in tone between different TYPES of caps, but in the voltage rating of the same caps, you will not find a tonal difference.

     
  12. JimmyR

    JimmyR Member

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    I use Sozo caps in most builds and they're only rated at 400V. They sound great.
     
  13. HandOfTheHost

    HandOfTheHost Member

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    Ah, you were referring to the original question, thanks for clarification.
     
  14. GearHeadFred

    GearHeadFred Member

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    Discussions on guitar amp tone is no place for a realist !!! :rotflmao
     

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