I'm using a true 8-bit DAC to play some low quality audio through some headphones. At the moment I'm just using a 300 ohm series resistor to limit the current to 10ma.
Do I need a series capacitor here to protect the headphones?
The DAC produces voltages from 0V to 3.3V. It does not produce negative voltages. Additionally, the DAC never actually seems to drop below 0.1V.
How do I know if I need a series capacitor to protect the headphones and how do I calculate it's value? Is a 10uF ceramic sufficient? High quality audio is not required, but I don't wish to pointlessly ruin it.