Current Doubler?

Discussion in 'Effects, Pedals, Strings & Things' started by yawiney, Apr 12, 2015.

  1. yawiney

    yawiney Member

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    All the PSUs I'm looking at (besides the Ciokolate) that do what i need voltage-wise would be under amping at least one of my pedals.
    Would a current doubler cable solve my problem? Does it take 2 of the outputs? Then it wouldn't solve the issue. Thanks in adv. for help on this.
    Oh, I'd like to avoid going Cioks if possible.
     
  2. coltonius

    coltonius Señor Member Silver Supporting Member

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    When you double the voltage, you halve the current. Sort of like sticking your finger over a water hose (less water comes out but at a higher rate).
     
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  3. yawiney

    yawiney Member

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    ^Thanks. That explains why so many switchable voltages have less ma when in higher voltage mode.
    What i'm wanting to do is add more current. Anyone know how a current doubler works?
     
  4. jdel77

    jdel77 Silver Supporting Member

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    Read up on current vs voltage.
    I'm not aware of any PSU's that double the current.
     
  5. gibs5000

    gibs5000 Member

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    The only method I know of to double the current is with cioks, they make a y cable that combines the total available mA from 2 isolated channels. Voodoo labs might have a similar connector as well. But either way, your still taking two channels to accomplish this. Don't think there's a way to increase current as current is like volume, you can't push basketball through a 3" drain. (Sorry, I'm a plumber by trade, that's the easiest way I could explain it).

    Voltage on the other hand, is like pressure, you can increase and decrease that to some extent, albeit limited extent.
     
  6. SteveO

    SteveO Member

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    The Voodoo Lab Mondo might be a consideration. It's essentially a Pedal Power 2+ and a Pedal Power Digital combined in the same chassis. Twelve isolated outputs, four of them good for 400mA each. The PP2+ can use a current doubler as well, but that will lower the total available outputs to seven. Oh-I almost forgot-the Voodoo Lab 4+4 is another one that has high current outputs.

    Another option, though one I have no experience with, is the Gig Rig.
     
  7. tanee

    tanee Member

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    What's wrong with cioks?
     
  8. yawiney

    yawiney Member

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    Nothing wrong with Cioks. I may end up going that way just wanted to avoid their propietary cabling system so i could use power cords i already have. Even with Cioks i'm still not finding what i need for the Whammy 5.
     
  9. jnepo1

    jnepo1 Silver Supporting Member

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    When doubling voltage with a voltage doubler adapter, the mA does not double. The mA output stays the same even though you will be using two taps to double the voltage.

    When using a current doubler adapter, the voltage stays the stays the same but the mA are combined.

    Voodoo Lab like Cioks, has both current and voltage doubler adapter and power cables. They do require two isolated taps. Cioks does have a voltage doubler cable (Flex cable) that only requires 1 isolated tap that can double voltage: 9/18 and 12/24. The mA ceiling is 50mA though.
     
  10. yawiney

    yawiney Member

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    Thanks. Was planning to use that cable if going Cioks. My Goodrich VP 18v says 100ma so the 50 might not work. So from what youv'e said, even if i used 2 taps i'd still only have 50ma coming thru right?
     
  11. MegaMan9

    MegaMan9 Member

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    I believe the Whammy 5 is around 265ma stated and ~185mA measured, what's the problem ?
     
  12. yawiney

    yawiney Member

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    Yeah I realized that last night. Was going by the 1300ma it says on the pedal.
     
  13. rhoydotp

    rhoydotp Member

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    I don't think this is mathematically correct or maybe I am confused. You are referring to Ohm's Law?
     
  14. jnepo1

    jnepo1 Silver Supporting Member

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    No, you will get 100mA.
     
  15. stinkfoot

    stinkfoot Member

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    Ohm's Law does indeed say that everything else being equal, if you double the voltage you'll halve the current. However, in this case not everything is equal. You're adding a second 9vDC, 100mA supply to the first, and the way you combine them dictates what happens.

    If you connect them in parallel (using a current doubler cable), you'll get 9vDC, 200mA.
    If you connect them in series (using a voltage doubler cable), you'll get 18vDC, 100mA.

    So Ohm's Law still applies, but with the new and different circumstances.
     
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  16. ballhawk

    ballhawk Supporting Member

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    Bumping this for diy wiring question. If I want to double the current (voodoo pedal power or the like)do I need to leave the ground unconnected at one of the taps to prevent a loop?

    And if anyone has a wiring diagram I'd feel better about making my own cable. I have plenty of adapters. I assume 2 plus+ out of 2 taps and solder them together at the end that goes into the pedal. Same for -minus with possible exception of one or the taps not being connected?

    Thanks
     
  17. stinkfoot

    stinkfoot Member

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    No, you need to connect both + and - on both plugs, to put the two outputs in parallel. Basically, you're wiring up a regular cable, then adding a second connection (from the second output) to the first. The "leaving the ground off on one of the wires" thing is sometimes done when you split a single output to two pedals. Here, you're doing the opposite - combining two outputs into one.
     
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  18. thinkwriter

    thinkwriter Member

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    What I did to power my El Cap using a Supa Charger:

    - Cut an old daisy chain leaving three tips like so:


    - This acts like a current doubler. Connect the two parallel ends to two isolated outputs of the same voltage (i.e. 9v). You can even use two outputs with different currents as long as they're the same voltage. The amperage will be summed.

    - Connect other end to El Capistan

    This has worked for me the last 3 years.
     
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  19. ballhawk

    ballhawk Supporting Member

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  20. Stratobuc

    Stratobuc Member

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    Have you looked at the Dunlop Iso Brick? Looks like it has almost anything covered.
     

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