Sony Walkman NW-A55 Gain Setting - What Does It Do? o_O

[Lalapuni]

NW-A55 has filtering settings: slow roll-off and sharp roll-off. I seem to like sharp roll-off a lot more and was able to notice the difference easily in while listening to "Naked Tongues" by Perturbator.
The setting I don't understand, though, is Gain. There's an option for 0db (set to the same level as PCM. This may cause distortion on some songs) and -3db (recommended gain setting). What is the difference and which should I use?

 

[PurpleAngel]

Basically, the gain setting enabled, should provide a slight boost in the voltage output for the headphone jack.
Lower Ohm (impedance) headphones, like IEMs should be fine for the lower setting.
Higher Ohm headphones should perform better with the higher gain setting.
Go with whatever gain setting your ears like better.

 

[Lalapuni]

Basically, the gain setting enabled, should provide a slight boost in the voltage output for the headphone jack.
Lower Ohm (impedance) headphones, like IEMs should be fine for the lower setting.
Higher Ohm headphones should perform better with the higher gain setting.
Go with whatever gain setting your ears like better.

Oh ok, thanks