one simple “best” way is to buy the most expensive pair of headphones not ‘earphones’, which has the impedance around ~50 Ohms !!! this type of headphones fits on any portable audio device (iPod, Any cell-phone,laptop soundcard ) and offers impressive sound-quality .
any headphone with a higher impedance needs a headphone amplifier and that means more money .
good headphones brands are Grado, Sennheiser , AKG . else you may buy the rest …….