Stepping down Voltage question

[Rizzo]

with dc i'd just use a bunch of diodes in series .7v drop each so you need like 7 of them

^^^This, or get one zener diode rated at 4 or 5 volts and wire it in series to the load.

Whether a resistor, diodes or zener is used, you are going to need to know how much current is being used so you can get the appropriate current/wattage rating for what you choose to use.