Design and features:The earphones have medium-high sensitivity so they can provide satisfying volume levels when used with home audio equipment and even lower-powered portable audio devices. The M4U 4 comes with six pairs of ear pieces of various types and sizes, a detachable 47-inch standard audio cable, a detachable 53-inch audio cable built-in mic and answer/music player control button for iPhone/iPod/iPad, and smartphone use, a 1/4-inch plug adaptor, a mini-plug-to-airplane-jack adapter, a removable shirt clip, and a carrying case.
Sound quality: We found the M4U 4 delivers sound quality sound quality that falls in the excellent range; while no headphone is perfect, the sonic shortcomings of this model are minor. The overall sound can best be summarized as clean and well balanced, but a little washed out. Bass (as in bass drums, bass guitars, stand-up bass, etc.) has good impact, has good detail and goes deep. The midrange (voices, guitars, horns, etc.) is even, clear, and fairly detailed. The treble (cymbals, the upper range of violins, etc.) is extended and also fairly detailed. The sound has a decent sense of liveliness and is generally open -- sound-wise when the audio program is playing it seems like you don't have anything plugging up your ears, although the upper midrange/lower treble does sound a bit dry (a little bland and lacking in reverberance).
Comfort: We found that these earphones fit and stay in place with no problems, but they produce a sense of pressure in the ear opening that might be uncomfortable for some.
