Sennheiser has announced the HD 660S2 open-back headphone, an overhaul of the well-reviewed cans at the top of its revered 600 series. The new model, available for preorder now, will sell for $699.95 and be available on February 21, 2023. That’s a $200 bump from the earlier model, so we should expect big improvements to justify the higher retail price.
The HD 660S2 feature improved airflow to the headphone drivers and an upgraded, lighter-weight voice coil. Sennheiser touts improved impulse response from the new coil and promises the change will bring “hyper-realistic textures to the forefront of any performance reproduction.”
This news story is part of TechHive’s in-depth coverage of the best headphones.
The other big improvement is to the low end, which Sennheiser claims will yield “deeper, clearer bass without sacrificing the expansive detail the series is known for.” Reviews of the earlier model often pointed out the underwhelming bass performance, so this should be a welcome improvement for anyone who enjoys hip hop, EDM, or other genres that emphasize bone-shaking lows.
Open-back headphones like the new Sennheiser HD 660S2 deliver a more expansive sound stage, but they’re not the best choice for private listening in public or when you don’t want to disturb other people in your home, because their design leaks audio into the environment.
Since the HD 660S2 is an open-back headphone, it will leak sound and not provide much in the way of noise isolation. That makes them best suited for at-home listening in a quiet space. Anyone else in the room is likely to be disturbed by the muffled playback that leaks from any open-back model.
Sennheiser says its engineers designed the new model in Germany, and that the headphone is being manufactured at the company’s factory in Ireland. The HD 660S2’s earcups feature Sennheiser’s iconic oval shape and plush earpads, which the company says places the updated model’s 300-ohm transducers at the optimal distance from the ear. The transducer surround, meanwhile, drops the resonant frequency from the 110Hz delivered by the original HD 660 down to 70Hz, a change that should improve the lows. The outer mesh grilles are designed to manage airflow at what Sennheiser considers the ideal impedance.
Sennheiser says its engineers redesigned the HD 660S2 to improved airflow to the headphone’s drivers and reduce the weight of its voice coil.
The HD 660S2 comes with two 5.8 ft user-detachable cables that terminate to a 1/4-inch single-ended stereo plug and a 4.4mm balanced stereo jack plug. A 1/4-inch to 3.5mm adapter is also included. The new model has bronze accents on a jet-black finish, which will distinguish the HD 660S2 from the earlier model. Since these are headphones that are likely to be used at home, they come with a protective storage pouch instead of a hard-sided case.
It’s been five years since the release of the original HD 660, and the new HD 660S2 will be substantially more expensive; in fact, they are the company’s most expensive over-ear model apart from its HD 800 S ($1,799.95) and HD 820 ($1,995) audiophile models. We look forward to hearing what Sennheiser has delivered with this new redesign.