My brothers and sisters were always listening to Journey in the late 70’s…early 80’s. Along with Queen, Floyd, AC/DC, Aerosmith, Led Zep, Beatles, VH, Cheap Trick……
I had to learn the hard way by frying a Fostex 4 track back in the day.
Polarity has to be the same.
Voltage needs to be the same.
Current requirement of the device being powered needs to be at or below what the power supply is capable of putting out.