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Sennheiser HD660S2 Open-Back Dynamic Headphones

Enjoy your music on a completely new level. An intimate, relaxed sound signature combines with outstanding precision and exceptional comfort — and now, extended sub-bass — for a deeply moving experience.

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Your new desert island headphone

Ever felt goosebumps from sound so real, it was as if the source was in the room with you? The non-fatiguing HD 660S2 gives people who love music an intimate way to connect more deeply with their favorite songs and artists. Breathtaking resolution and precision take you closer than ever to instruments and vocalists. Yet the sound is natural and balanced, never harsh or brash.

This warm, inviting signature combined with extended sub-bass makes listening uniquely pleasant and rewarding. And with comfort this good, it practically begs you to keep going for endless sessions. That’s how HD 660S2 combines the best of many worlds to give you an intimate experience you won’t want to live without.

Sub bass expands the entire sound

Traditionally, audiophiles don’t get too excited about sub-bass. It can easily get sloppy or boomy and become a distraction. And that’s a shame — because there’s so much more to experience here than just the gut punch of a kick drum. Did you know the low B of a 5-string bass vibrates at 30.9 Hz? Or that the lowest note on a concert piano comes in at 27.5 Hz? And of course, extended sub-bass makes bass-heavy genres sound fantastic, too.

And that’s the magic trick here. In doubling the sound pressure at the very lowest frequencies, we’ve nevertheless retained extraordinary precision and balance throughout the sub-bass, mid-bass, and beyond. Most impressive is how this affects the listening experience. Extension on the low end changes everything — by creating more space for the sound. Against a deeper backdrop, highs feel more brilliant, the soundstage deeper, and emotions stronger.

What's In the Box

• HD 660S2 headphones

• 6.3 mm cable (1.8 m), 4.4 mm cable (1.8 m)

• 6.3mm to 3.5mm adapter

• 6.3 mm (1⁄4 inch) to 3.5 mm adapter

• Carry pouch


Transducer principle: dynamic, open

Transducer size: 38 mm

Frequency response: 8 – 41,500 Hz

Impedance: 300 Ω

Sound pressure level (SPL): 104 dB

Total harmonic distortion (THD): <0.04% (1 kHz, 100 dB)

Weight: 260g

Magnetic field: 2.5mT

• Capacitance w/ 2m Cable: 135pF

Weight: 465g

HD 660S2 Driver Assembly


About Sennheiser

You can't go wrong with any Sennheiser product, from the classic HD 660S to the detailed HD 800S. Sennheiser's headphones are known for quality, comfort, and a sound signature that can please any taste.