The new HD 660 S2 lets you enjoy sophisticated audiophile sound in even more listening situations. Thanks to its lower impedance, it delivers reference-class sound also when connected to hi-res mobile players, thus offering much greater versatility. The HD 660 S2 is an elegantly designed piece of high-quality engineering that indulges the demanding listener with aural precision and great wearing comfort.

The HD 660 S2 has been created to enjoy music in supreme quality and from many different audio sources. Thanks to its low impedance it also offers reference-class fidelity with hi-res mobile players. Naturally, the HD 660 S2 reveals its full potential when it is connected to the balanced outputs of a dedicated headphone amplifier or to the balanced output of a mobile digital audio player. Accordingly, it comes with a choice of cables for just about any occasion. All cables are made of highly conductive OFC copper, featuring very low handling noise and sturdy para-aramid reinforcement.

• Impedance: 150 Ω
• Connector: 6.35 mm / 4.4 mm Pentaconn
• Frequency response: 9 – 41.500 Hz (-10 dB)
• Sound pressure level (SPL): 108 dB at 1V 1kHz
• Ear coupling: Over-ear (circumaural)
• THD + N, total harmonic distortion and noise: < 0,04% (1 kHz, 100 dB)
• Transducer principle (headphones): Dynamic, open
• Weight w/o cable: Approx. 260 gr. (without cable)