madbeanpedals::forum

Projects => General Questions => Topic started by: bakelo on November 03, 2011, 08:02:35 PM

Title: -9v effects powering (Range Master / Mangler)
Post by: bakelo on November 03, 2011, 08:02:35 PM
I was reading about wiring these effect and I noticed you can use a voodoo labs pedal power vs a battery. Can anyone explain how this works? Sorry for all the noobie post.
Title: Re: -9v effects powering (Range Master / Mangler)
Post by: JakeFuzz on November 03, 2011, 09:14:22 PM
I am a big fan of using a charge pump. Most fuzz and treble booster circuits are small enough to accommodate the additional circuit (I think it is just the CP and a single capacitor).

The reason you cant daisy chain with positive ground pedals is that at the jack the ground (sleeve) connection between the two pedals will short out the power supply causing very high current draw which can fry the p sup. The charge pump operation isolates the supply and produces -9 volt with the same ground reference so it works just fine with your other pedals. My guess is the voodoo labs unit does negative full wave rectification in addition to positive rectification to produce the negative 9 volts with the same ground.  

Edit: hmm looking at the VL power supply there isn't a -9v output. They are isolated though so my guess is there isn't a common ground between the outputs (maybe independent taps off of the transformer  ???)
Title: Re: -9v effects powering (Range Master / Mangler)
Post by: dwstanford on November 04, 2011, 11:45:25 AM
The voodoo labs pedal power comes with an adapter with a red tip on one side that flips from negative center to positive center to accommodate pos. ground pedals.  If you already have the pedal power or you were thinking of getting one anyway, thats a good solution, but you can actually use the same type adapters for a wall wart style plug.  You just can't daisy chain it with other pedals.  The other solution would be a charge pump as Paul suggested.  With this solution, you don't have to worry about losing your adapters or anything like that.  It just plugs into your usual power supply and can be daisy chained with other effects.  I recommend that idea, but i wouldnt do away with the battery power to accommodate it.  I like to run my pos. ground effects with carbon batteries when i have them and when i dont, i use the charge pump.  I have a voodoo labs pedal power 2, but i can never keep up with the adapters, so i rarely use them.
Title: Re: -9v effects powering (Range Master / Mangler)
Post by: jkokura on November 05, 2011, 02:40:22 PM
Wooooah.

The Voodoo labs reverse polarity cable is white. The Line 6 cable is red. It would be bad to confuse them I think. The Line 6 end is also 2.5mm.

Jacob
Title: Re: -9v effects powering (Range Master / Mangler)
Post by: dwstanford on November 05, 2011, 07:11:14 PM
Yeah, youre right Jacob.  The rev. polarity plug is white instead of red.  Whoops.   8)  Like i said, i rarely use it.
Title: Re: -9v effects powering (Range Master / Mangler)
Post by: nzCdog on November 05, 2011, 07:15:46 PM
Quote from: JakeFuzz on November 03, 2011, 09:14:22 PM
I am a big fan of using a charge pump.
+1 Messing with different power supplies or coloured leads is a pain, this is a great option IMO
Title: Re: -9v effects powering (Range Master / Mangler)
Post by: crash on November 07, 2011, 05:37:46 AM
Some effects you can build "upside down" as I call it.  Where you can make a PNP Rangemaster, 9V, negative ground that will work fine with your power supply and with other pedals.  I built my OC44 Rangemaster this way and it works great.