80's_Thrash_Metal
Slightly_Glazed_Believer
It is from the 90's. Not that "vintage" LOL
Iirc some of the older pedals sometimes took a positive tip and not a negative tip......or vice versa.
Some power supplies are opposite of what you may need. So even though they may be 12v, and they may fit in the hole....they could be wired backwards for a specific application.