Hello! I just bought an guitar power supply with 10 isolated outputs (9v, 12v and 18v).
When I hooked all up for the first try I used boss Ds-1 pedal and by mistake powered it up to a 18v output and turned it on for about 5 sec (amp was off). Is there a chance that I damaged the power supply or the stompbox by any chance by doing this? Afterwards I tryed to plug pedal in 9v output and all seemed to work just fine..

any expirience with what could go wrong in this sort of situation?
If it still works then you did nothing. If it doesn't work then you broke it.

Don't worry. Don't do it again, either, though
thanks for quick response! I'm really pedantic about these things, just wondering - in case something would go wrong - it would be the stompbox or the power supply?
Stompbox. Too much voltage would fry the internal power system in the pedal. That's why you'd know right away if you'd done some damage. When you smoke a pedal's power supply, it's gone and the pedal will not work. If you ran it on the wrong voltage for months, you might damage it more subtly. But 18V into a 9V pedal for a few seconds will either not cause any real damage or it will kill the pedal right away.
stompbox, it would fry the electrolytic capacitors.
Someone is wrong on the internet. Only you can help.

Quote by Tulkas

Stairway is required on any list of anything involving the words guitar or song, I believe Congress amended the constitution in order to put it into federal law.
I would be very surprised if an 18V supply damaged a DS-1
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