Hum at 12VDC - no hum a 9VDC

[Fasel]

Hi Team,
Has anyone had any hum issues when running say a PPF at 12V? I have a Voodoo Labs PP2 and until recently, was running my PPF at 12V. I started getting a hum, sort of like a mains power 50/60Hz type of hum or like an earth loop hum, and after changing all leads and power connections, found that when I switched the PP2 to 9V, the pedal was quiet. The PPF is on a large pedal board with plenty of other pedals. The problem seemed to just come out of nowhere.
Any ideas?

[Carlos]

is it in outlet 5 or 6? when set to 12v they are un regulated, so can go as high as 16v....... try 1-4 or even outlets 7 or 8........


if its not that, im not sure....

[Carlos]

is it in outlet 5 or 6? when set to 12v they are un regulated, so can go as high as 16v....... try 1-4 or even outlets 7 or 8........


if its not that, im not sure....

[Donner]

Good question ....I wonder if its perceived hiss --- as in raising the voltage raises the headroom and clarity ....

[Fasel]

Yes. I am using outlets 5 & 6. It sounds something similar to an earth loop hum. They are nice and quiet at 9VDC.

[Carlos]

if you want to power with 12 volts, use outlets 1-4 instead. those outlets are regulated so the voltage wont fluctuate much giving you the issues.

[Fasel]

Thanks for your help, Carlos. That all makes sense and seems to be the problme. I have my EH DMM using my first two outlets to give me 24VDC. That only leaves me with 2 other outlets to use a 12VDC. I have to admit, I am really hard pressed to notice any difference in running my pedals at different voltages. I have only been able to compare two PPFs side by side. There was bugger-all tone differences - at bedroom volumes anyway. Maybe I need to crank it and try it again. All the other BJFs I have seem to sound the same at 9V and at 12V. I have not gone any higher than those voltages. Anyone else a bit let down after trying this?

[Carlos]

i find it hard as well to hear a difference, but i think most of it is a different feel. like headroom, or drive getting more saggy, as apposed to frequency changes.