I want to use a "capacitor-less" headphone amplifier that doesn't require DC blocking capacitors at the output.
I found a headphone amplifier that has a negative charge pump that generates an internal negative supply voltage, which removes the need for output caps. However, I found these parts are more expensive. As an alternative, I found a lower cost headphone amp that has a "phantom ground" configuration to eliminate the need for output coupling caps, as shown below:
Is there any potential issue with directly connecting the phantom ground (Vout3 in the diagram) to the headphone's ground? What's the disadvantage of this method over the negative charge pump method?