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?


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 '19 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 '19 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. Sep 26 '19 at 16:41

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 '19 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 '19 at 15:21

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