just as an alternative suggestion why not use a pair of the shure in-ear monitors? they will give you excellent sound and connect the same as on an ipod/mp3/cd player, in the headphones output ...i am guessing they start at about US $70(out here they are about $110) for the EC-3 model, they have better quality more expensive ones too!!)...as they are in ear, they are very small and hardly noticeable...anyhoo just a thought.
cheers
dennis