Sennheiser HD 559 Open Back Over-Ear Headphones Black NOB ————- Sennheiser HD 559 Powered by Sennheiser proprietary transducer technology, these comfortable and attractively designed headphones are the key to unlock the true potential of your home entertainment system. As successor to our popular HD 500 series, the Sennheiser HD 5 model range offers high quality and value in any aspect. Powered by Sennheiser’s proprietary transducer technology including the “Ergonomic acoustic refinement” (E.A.R.) design, which channels the audio signal direc