Most headphones used with portable electronics are low-impedance, around 32 ohms. This is because the power supplied by the device is limited due to it being battery powered, and the low impedance in the headphones allows higher volume levels.
From my basic electrical engineering courses, my instinct is that higher impedance headphones would also create a more level frequency response, thus being more true to the original signal. Is this true?
In relation to achieving optimal sound quality, is there any advantage to pairing high-impedance headphones with an amplifier for listening on an MP3 player or laptop, as opposed to just using low-impedance headphones?