If you mean the impedance, I believe it’s 16 ohms. That seems to be the same for all Sansas.
If you mean the effort needed to insert the headphone plug, it’s higher when the player is new, and decreases as the jack is “broken in”. Many people have complained of sound problems (mono, instruments only ( “karaoke effect” ), or popping/crackling in the phones) only to learn that they hadn’t fully inserted the headphone plug.
