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My Pedal Power 2 Plus has two 9v 250mA outputs and several other 9v 100mA outputs. I have a pedal that needs 9v 280mA.

I have a Y-cable that can connect two power sources to one pedal, but it's meant to provide a pedal 18v, not necessarily adding the mA. I need to remain at 9v but combine mA provided. How can this be done?

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You're trying to combine "parallel DC power supplies." It's not as simple as Lego, though, because typically one supply is a few millivolts higher than another, which drives the second one in reverse. If you're lucky, nothing catches on fire besides that power supply which, to its astonishment, has become a power drain.

With a few diodes rated for that current, you could solder up a circuit. Or you could do something even fancier. But for the numbers you need, it's much simpler and faster to just use a household 9V battery. They can supply 500 mA for about an hour. Or buy or scrounge a 9V wall wart rated for your 280 mA.

Edit: you can safely parallel-connect multiple 9V outputs of Voodoo's Pedal Power 2 Plus, because those outputs are isolated from each other and probably have other safeguards because the unit is popular despite its price exceeding $20 per output. It's clearly not from a fly-by-night Pacific factory.

  • Lasting about an hour won't even service a gig or rehearsal! Maybe a much bigger 9v battery will. Wallwart - dedicated, is the real answer. – Tim Sep 25 at 6:42
  • I was able to find two different cables: a voltage doubler (connects two 9v to make one 18v) and a current doubler (connects two 9v to make one 9v, but double the mA). Both by Voodoo Labs. This might be what I was looking for. – gator Sep 26 at 12:31
  • Yes, the current doubler cable will work -- with that particular 8x power supply safely, but unsafely with two generic wall warts. Edited my answer. – Camille Goudeseune Sep 26 at 16:41
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Practically, the 250mA output will probably be just fine. Try. It's a pretty poor power supply that can't cope with a nominal 12% overload.

  • Very true - also, often that max current draw is probably when gain stages are turned up to max, so if the pedal is used at its midrange I would expect a lower current draw (probably) – Doktor Mayhem Sep 25 at 13:36
  • You were right. Plugging it into the 250mA port, it seems to be working fine. I haven't cranked it, though, maybe if I do some of the heavier effects or chain multiple effects (it's a multifx pedal) it would sag a little, but so far, so good. – gator Sep 28 at 15:21

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