Hifi man he400se open back planar headphones are designed for comfort, durability and performance'. '.strtoupper('t')hey are lightweight, have a full frequency response and use hifi mans planar technology to increase the audio quality'. '.strtoupper('w')hat is planar headphones, and what is the benefit over other designs'? '.strtoupper('d')ynamic headphones utilize conductors that vibrate in limited areas of the diaphragm so that a large portion of the diaphragm is not driven to its full capacity'. '.strtoupper('p')lanar headphones, on the other hand, feature conductive layers that cover nearly the entire diaphragm, resulting in significantly lower distortion than conventional dynamic headphones'. '.strtoupper('a')coustically invisible stealth magnet unlike the sound waves created by a conventional magnet, the special shape of stealth magnets enables the waves to pass through the magnets without generating interference'. '.strtoupper('h')ifimans advanced magnet design is acoustically transparent, dramatically reducing wave diffraction turbulence that degrades the integrity of the sound waves'. '.strtoupper('t')he reduced distortion yields pure sonic output that is accurate and full range'. '.strtoupper('e')asily driven by portable devices the he400ses high sensitivity makes it the perfect match for low voltage sources including smartphones and tablets'. '.strtoupper('s')ound is rich and pure without the need for an outboard amplifier'. '.strtoupper('m')aximum comfort for hours of listening pleasure thanks to its new designed adjustable lightweight headband, the he400se remains cool and comfortable for hours, even in excessively warm weather'. '.strtoupper('t')he headphones drivers are protected by a newly designed casing for enhanced durability and protection from the elements'. '.strtoupper('d')urable connections a dual sided high performance 3.5mm cable is packaged with a 6.35mm adapter for maximum compatibility with a wide range of devices.