reverse polarity of +9V Dc

[Gledison]

Hello everyone!
Im wondering i could use a plug to invert the polarity of the 1spot Dc adapter for pedals with positive ground. i read different threds but didnt really understand the thing.
if its possible to invert with a plug, i could use this pedal together wiht others negative ground using a daisy chain right? i mean, only one of the plugs of the daisy chain would be inverted...
sorry, but thats why im a diode destroyer
cheers guys

[RobA]

To mix the polarities on the taps on a power supply, they must be isolated taps. Since the 1 spot is daisy chained, it can't be isolated as far as I can see (I don't own one).

Just think about what it is doing electrically. You tie the ground of the audio input to a power supply rail. In one pedal that'll be on the negative rail. On the second pedal, it would be the positive rail. So, you've now tied the negative rail to the positive rail through the audio ground. Dead short.

Edit:
I think I remember seeing somewhere though a plug adaptor that used a charge pump internally to generate a negative rail right at the tap. That would work for you.

[oldhousescott]

Like RobA stated, you need a PS with isolated taps. You could buy two One-Spots, one to power your positive ground pedals, and one to power your negative ground pedals. Yes, you'd need to invert the polarity on the plug of the one powering your positive ground pedals. I believe they sell an adapter for that.

Another possibility is to buy from Madbean and build RoadRage circuits to put inside all of your positive ground pedals. Then you could use a single One-Spot to power all your effects.

[RobA]

^ Do this. The Road Rage is great. It means your pedal will work the same as all your other pedals. It's future proofing for any PS you may end up using.

[davent]

Aren't most positive ground pedals some sort of germanium booster/fuzz with a minuscule current draw? Use a super bright LED so again very low current draw, why not just leave it running off a battery?

dave

[Gledison]

Thanks a lot for the suggestions.
actually I didn't build any positive ground yet. just want to plan ahead before facing troubles!!
Dave is right, maybe using a baterrry for this positive grounds might be the easiest solution.
I will check the Road rage as well
thanks guys