With which operating voltage can I operate the ODR pedals?

The current pedals (ODR-1 from 2020 with Bass Cut/ ODR-1 30th Anniversary / ODR-1 Ltd and ODR-mini) can be operated with a DC voltage of 9-18 volts.

Older ODR-1 without bass cut switch only from 9-12 volts DC.
Always pay attention to the polarity and voltage!

A higher operating voltage allows the sound to have a little more headroom and thus a little more transparency. This is of course a matter of taste and not always desirable. Even a very low voltage (dying battery) is sometimes appealing. Here you get almost sounds like a FUZZ.