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Can i bypass an AC/DC power supply to AC/AC? Answered

I recently aquired an used guitar effect pedal, a Behringer X Vamp, to be more exact.
It is 2nd hand so it came without the power supply. I know it runs on AC/AC and i have an AC/DC one, so my question is:
is there a way to bypass the power supply or the pedal itself so it can run with the supply i have?

thanks in advance,
stay well


Hey, Not sure if you are just interested in the idea of using your old DC supply to power the circuit or if you simply want a supply to test/power your pedal. I see lots of replacement power supplies in the UK (on ebay) but few in the States. If you have no luck with modifying it to work with your existing supply you could buy a 9V~AC supply for a similar pedal (eg Here is one for a Digitech TimeBender delay which can supply ample current 1.3A at 9VAC for $8). Either way hope you have success.

To be honest i was really aiming to transform the one i have.
Tell me, will the 1.3a make a difference in comparison to the 600ma?

Only difference is it will run cooler and is probably heavier.

Consider as an example, the 100_watt light bulb in a lamp and replace it with a 60_watt light bulb which only draws the needed 60w from a fixture that could supply more power.

I see. Nice.



1 year ago

Hi again,

thanks for the replys.

steve, i saw it in the manual and by the time i've looked it up in a forum. If i find it again i'll post it.

This i know, with the dc out plugged in the pedal turns on but no sound passes through. I got a variable current ac/dc supply from 1.5 to 12v.

ye, this was the forum post i saw when searching for a solution.
Altough it provided me with lots of info at the time, it didn't gave me a solution that wouldn't imply buying a 9v Ac 600ma power supply.

yee :)

thanks man.
this is very helpfull.
you know, i saw this video:


it gave me a solution but without the theory behind it, so this is a plus.


1 year ago

Not trying to discredit you Ice but i think it takes 9v AC at 600ma.

As friends have pointed out to me its 9 volts AC at more current 600ma

I RETRACT my earlier statement as the site pointer I used does not go anywhere....

So I carefully looked at the input power which does say 9v~ --> 9 volts AC.


I could not find a schematic but would bet there is no transformer in that case which would lead me to suggest there is a bridge rectifier and regulator inside and that would work on DC too.. That also suggests you could try the DC to see if I'm right.

Sorry for the misleading previous information.


no needs for sorry ;) i aprecciate the reply.
i've tried with the dc but what happens is the pedal turns on and i can change settings and what not but still, when the output jack is plugged no sound comes out.
I did found a video on Tube where this kid bypasses the circuit in the ac/dc power supply and connects the output directly to the Ac input.

I don't know if i can post the link here but i'll try it asap and i'll post the results here for the sake of it.

thanks again.

What kind of power supply have you got ? How do you know the pedal needs AC ?