Sennheiser HD660S2

Sale price $549.95 Regular price $799.95

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Sennheiser HD660S2

Sennheiser headphones have inspired generations with their balanced, natural reproduction. Recognized as a benchmark for neutral audiophile sound, the original HD 600 from 1997 still shares visible and audible DNA with the latest in the lineup, the HD 660S2. 

Despite the previous HD 660S from 2017 standing as one of the world’s most popular audiophile headphones, some customers nevertheless wanted one very specific enhancement: even deeper bass. Enhancing this heralded audio design without detracting from its many strengths was, however, a daunting task. So, our engineers set out to systematically identify and exploit every opportunity in their quest to improve on the acclaimed HD 660S design.

We adjusted the compliance of the surround, for instance, dropping the resonance frequency to 70 Hz. Considerable effort went into optimizing the airflow around the transducer. The coil in the HD 660S2 has also been revised to match the legendary HD 600 & 650, resulting in an impedance of 300 ohms. The new coil exhibits much higher magnetic force and electrical damping for cleaner impulse response. It also increases sensitivity over the entire frequency spectrum by using the magnet’s air gap more efficiently.

Taken together, these efforts and more have paid off in spades. The new version builds on all the strengths of its formidable predecessor; the same world-class precision and resolution still let you pick out individual instruments like with no other headphone. But sound pressure at the lowest octaves has doubled, so now, you can feel the music more than ever before — with all the depth and weight that ultra-low frequencies invoke. The unique combination of impactful bass combined with the warm tuning and smooth treble is a revelation for music lovers, an even better way to lose yourself in comfortable, non-fatiguing, high-end sound — while feeling its full low-end power.


"HD660S2’s microdetailing and intimate soundstaging is mind blowing"

read the review in Headfi-org

"The audio quality of Bluetooth headphones has come a long way over the last half-decade, but if you really care about the sound coming out of your cans you’ll want a wired pair. One of our favorites is the just-released HD 660S2 from Sennheiser; it’s the latest iteration of a beloved pair of over-ear headphones that the trusted German audio company has been producing for nearly 30 years now. Because they’re over-ears, you can really only use them home—or in a quiet space where you have some privacy—so they’re not as convenient as a lot of the other headphones on this list, but that won’t matter once you press play. These headphones are part of the brand’s audiophile line, and with good reason—their new 300-ohm transducers and perfect left-right balance allow them to produce a true-to-life sound with real depth. If you’re the sort of person who loves listening to new details in your favorite music, this is the pair for you.—BH"

"In very short we can say the HD 660S2 is a great headphone with an excellent price/quality ratio.

Where the Sennheiser HD 660S was good, it to me never was the headphone that could make me completely forget about the HD 600 and HD 650. That’s exactly what’s different with this new S2 update. This time I do feel that people in 10 years’ time will still be talking about the HD 660S2, just like they did with the HD 650 and HD 600. The original HD 660S did not get our recommended buy award, but I feel the sound quality has improved in every possible way here. As such it is getting our Recommended Buy Award this time, and the HD 660S2 now is featured on our Best Headphone list"

read the review in Headphonia


  • Transducer Principle: Dynamic, open.
  • Transducer Size: 38mm.
  • Frequency Response: 8 Hz - 41,500 Hz.
  • Impedance: 300 Ω
  • Sound Pressure Level (SPL): 104 dB (1V)
  • Total Harmonic Distortion (THD): < 0.04% (1 kHz, 100dB)Weight: 9.17 oz (260g)
  • Magnetic field: 2.5 mT
  • 38mm high-performance transducers built in Ireland
  • Steel mesh damping follows the driver’s geometry to control air displacement for precise sound.
  • Vented magnet system: The magnetic yoke includes milled air vents for optimal ventilation to minimize distortion.
  • Aluminum voice coil: Specially developed ultra-light voice coil with 300-ohm impedance for excellent impulse response.
  • Open-back earcups: Facilitate the natural expansion of sound waves for a hi-fidelity spacious soundstage.
  • Exceptional comfort: Open elliptical earcups provide breathability and luxuriously comfortable velour pads provide hours of fatigue-free listening.
  • Outstanding build quality: Designed in Germany, made in Ireland, each element is carefully selected to meet exacting standards.
  • Detachable cables: Para-aramid reinforced cables with OFC copper ensure signal integrity and a very low handling noise.
  • Ergonomic design: The low total weight and ergonomic headband eliminate potential discomfort on top of the head
  • Global 2-year warranty: Offers peace of mind for your audio equipment investment.

What's Included

  • HD 660S2 headphones
  • 6.3 mm cable (1.8 m)
  • 4.4 mm balanced cable (1.8 m)
  • 6.3 mm to 3.5 mm adapter
  • Carry pouch

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