I want to put a phantom power indicator LED on my 9k. What size resistor should I use to limit the current from 44-48v to an acceptable amount for a standard LED?
Doesn't sound like a blue one (which seem to give piercing amounts of light so should be tamed imho), but generally just try what gives the desired amount of light. Depending on colour/brightness/type/mounting you might need to adust the resistor value.