The HD 555 features a special internal Surround Reflector, which generates an extended spatial sound field,making it the ideal headphone for home theater,as well as music.Other innovative features include Sennheiserﾒs E.A.R.technology and optimized Duofol diaphragms for a new level of audio enjoyment.Overall listening pleasure is combined with outstanding wearing comfort.

Features:

• Open-Aire ?,circumaural,dynamic,stereo headphones
• Ergonomic Acoustic Refinement (E.A.R.)enables ideal sound
  channeling for a new kind of listening experience
• State of the art,advanced Duofol diaphragms
• Highly optimized,field-strengthened neodymium ferrous magnet systems
• Outstanding comfort for long listening sessions
• Velour ear pads even allow wearing eyeglasses without loss of comfort
• Longevity through exchangeable components
• Lightweight aluminium voice coils for high efficiency and excellent dynamics
• Surround reflector improves spatial sound characteristics
• 2-year warranty

Specifications:

• Frequency Response: 15 - 28,000 Hz
• Nominal Impedance: 50ohms
• Max Spl: (1kHz, 1Vrms), 112dB
• Weight: 9.1oz
• Transducer Principle: Dynamic, open
• Thd: <0.2%

Headphones Specifications:

• Transducer Principle: Dynamic, open
• Weight Wo Cable: 9.1oz
• Characteristic: Spl 103dB
• Ear Coupling: Circumaural

Connectors:

• Connector: 6.3mm stereo jack with 3.5mm adapter(both gold plated) 10ft cable, (OFC), single-sided, changeable

• Data Sheet