Sennheiser HD 660 S2 Headphones

Sitting at the top of Sennheiser’s HD 600 Series, the HD 660 S brought listeners exceptional transparency with excellent low-end in an open-back build. Now, the brand is back with the HD 660 S2: a second-generation standout with even more low-end, thanks to an extended sub bass. Directing their attention to the deepest areas of the frequency spectrum, Sennheiser’s engineers nearly doubled sound pressure without compromising fidelity in the low end, the mids, or the highs. The result is an ultra-wide frequency response range (8 hertz to 41.5 kilohertz) with plenty of detail and next to no noise—thanks in part to 38-millimeter dynamic drivers hand-tuned for accuracy and 0.04% total harmonic distortion. Connected to these drivers, steel mesh damping follows the driver’s geometry to control air displacement for extra precision, while an ultra-light voice coil with 300-ohm impedance delivers truly impressive impulse response. Completing the sonic experience, open-back earcups create an expansive soundstage with class-leading comfort Sennheiser fans have come to expect.