The Sennheiser HD 660S2 is a premium open-back dynamic headphone designed for audiophiles seeking exceptional sound quality and comfort. Featuring improved transducers with ultra-light aluminum voice coils, the HD 660S2 delivers an extended frequency response from 8 Hz to 41.5 kHz, offering deep bass, detailed mids, and sparkling highs. With an impedance of 300 ohms and a sensitivity of 104 dB SPL/V at 1 kHz, these headphones are ideal for both home hi-fi systems and high-quality portable audio players. The ergonomic design ensures long-lasting comfort during extended listening sessions thanks to plush velour ear pads and lightweight construction. Sennheiser is renowned worldwide for its commitment to innovation in audio technology since its founding in Germany in 1945. The company actively pursues sustainability through eco-friendly packaging, energy-efficient production processes, and responsible sourcing of materials?helping reduce environmental impact while maintaining top-tier product quality. By choosing the HD 660S2, customers not only enjoy outstanding sound but also contribute positively towards sustainable practices.