Sennheiser headphones have long life due to easily replaceable parts and are extremely comfortable due to soft, crackle-free ear pads. Bass reproduction is below the human audibility threshold (15Hz) Overall listening pleasure is combined with outstanding wearing comfort. Enjoy music in a completely new way. Advanced Duofol diaphragm technology almost eliminates standing waves inside the capsule The open, dynamic HD 5 is a classic all-rounder and an affordable entry point into the audiophile 500 Series. It is fitted with innovative Ergonomic Acoustic Refinement technology, ensuring that the sound is accurately channelled into the ear