The HD 600 is the audio purists choice for reference playback. An instrument of Sennheisers passion for perfect sound, it is globally recognized as the standard for analytical high-fidelity listening - even 20-plus years after its release.Purpose-built to vanish when the listener presses play, the HD 600 is the benchmark reference headphone for both analyzing and enjoying your hi-fi setup. This disappearing act starts with an innovative, systematic approach to sound reproduction using transparency as the driving principle. Leveraging Sennheisers progressive production techniques and computer-based transducer optimization, it perfectly fuses the art of sound with the science of it.