12v pedals

1. Can you run guitar pedals at 12V?
2. Can you power a 12V pedal with 18V?
3. Why do pedals need batteries?
4. Is it bad to daisy chain pedals?

Can you run guitar pedals at 12V?

Using a 12V adapter on a pedal designed to only handle 9V can completely destroy it. There are some guitar pedals built to handle voltages higher than 9V. Those pedals will work perfectly fine with a 12V adapter. Check the pedal's manual before you try plugging a 12V adapter into any pedal.

Can you power a 12V pedal with 18V?

A built in 12V battery will not charge with 9V. Generally you can safely plug an 18v pedal with 9 or 12 V but there is a good chance that it will work poorly... (although it might give an interesting distortion effect).

Why do pedals need batteries?

Each pedal is completely isolated from each other (unlike daisy chaining) so you get no AC noise or signal issues. Batteries also give you the freedom to position your pedals wherever you want without needing to run a power cable to the pedal.

Is it bad to daisy chain pedals?

Despite the chatter, daisy chaining your effects is really not a bad thing to do. These power supplies mainly get a bad rep because of people misusing them, not understanding amperage, and trying to power way more pedals than the adapter is actually capable of powering.