this question is for the "electronic genuis'

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videodrone

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i have a dilema, I am getting a power supply unit that will power all my pedal and it got great reviews on not coloring sound and so on.

BUT....... it only has 4 DC outputs, so you have to daisy chain your pedals (no problem so far) cuz each of the 4 DC outputs gives off 400 MAs, and I belive the average boss pedall uses about 25-40 MAs,

BUT......... is it wiser to try and spread the pedals all around on the 4 DC outputs eqaully to take up the the same amount of MAs? Or does it not matter as long as there getting enought MAs to power the pedals?

by spreading around the MAs equally, will this improve the pedals tone? getting the most out of it?
 
As long as a power supply is reasonably quite source able to provide enough current, the only reason I can imagine why it would or wouldn't "color" the sound of the pedals is because of it's output impedance. I can guess that somebody might have designed a power supply that has the same output impedance characteristics as say a 9V battery. If this were the case, then you wouldn't want to daisy chain the pedals. You would just want to use one pedal for each specialized output in order to get the right "effect".

Oh there it is. I just looked on the Energizer site for the specs on a regular 9V battery and it does indeed show that the maximum output current is about 400mA. So there you go. That power supply is probably trying to act like a set of four 9V batteries.

barefoot

http://barefootsound.com
 
In order to get pure dc like the battery, there has to be a fairly big cap on the output of the transformer after the diode or the bridge. without it you can get noise from the varying voltage between humps.
 
darrin_h2000 - in lamense terms, what does that exactly mean? I know theres a cap of 400Mas, but I dont nkow if that is after the diode or bridge. How can I tell and what does that exactly mean? and what will voltage humps do? are they a issue that is important? or minor?

sorry so many questions but thats the only way a person can learn
 
The "bridge" rectifier is a set of diodes that change your voltage from AC to DC voltage that your pedals require. The transformer before the bridge steps down the voltage to 9VAC then the rectifier changes it to DC.

Hook 'em up like barefoot said.
 
As long as the stomp boxes don't draw more current than the power supply can provide for each pwr output that the stomp boxes are connectedf too... it doesn't matter.
 
DJL said:
As long as the stomp boxes don't draw more current than the power supply can provide for each pwr output that the stomp boxes are connectedf too... it doesn't matter.
Click to expand...
Not exactly. The 400mA maximum short circuit current spec given for a 9V battery tells us the battery has a 22.5 ohm internal resistance. Now the power supply or battery is as much a part of any circuit as the op amps or any other component, so its impedance (sort of like time dependent resistance) will effect how the circuit performs. Power supplies with output impedances such that they provide about 10 times the RMS current consumption of the circuit are typical for line level devices. In other words they're made much bigger than needed so they appear to be, for all intents and purposes, perfect voltage sources.

When I first saw this thread I was thinking the battery might actually have a much smaller output current (higher internal resistance) and that good pedals might be designed to work optimally with low current supplies. But 400mA is pretty good, so any quiet 9V supply capable 400mA or more would work just fine. But I wouldn't go much lower.

barefoot

http://barefootsound.com
 
I have a power supply that has 4 DC outputs and each 1 of the 4 have 400Mas each.

Should I spread teh pedals around to take up even Mas on all 4 of the DC outputs or does it not matter as long as there getting there Mas?
 
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