
Despite the HD 660S’s standing as one of the world’s popular audiophile headphones, some customers nevertheless wanted one very specific enhancement: even deeper bass. Because whether it’s a thunderous crescendo of timpani or the pulsating beat of electronic dance music, there is nothing like accurate, powerful sub bass to infuse your listening with drama. Audiophiles—and anyone looking for comfortable, non-fatiguing, high-end headphones—can now get even more impact and emotion from the HD 660S2. The headphone’s warm, relaxed tone is reflected by their timeless styling with elegant bronze accents. With its open-back design and outstanding comfort, the HD 660S2 is also destined to be a favorite for long listening sessions. This 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. Or experience the joy of discovering sonic details in recordings you’ve known for years—now underscored with more and deeper low end. Indeed, the standard-setter for extended listening has now become the standard-setter for extended bass as well. 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 coil offers a high magnetic force and electrical damping for a clean 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. Sound pressure at the lowest octaves has doubled. Now, you can feel the music more than ever before—with all the depth and weight that ultra-low frequencies invoke. The lowest A on the piano (27.5 Hz) or the pounding root note of a bass drum (45-60 Hz) are just as big, expansive, and imposing as if they were live. The unique combination of impactful bass combined with the warm tuning and smooth treble will be a revelation for audiophile listeners. It’s an even better way to lose yourself in comfortable, non-fatiguing, high-end sound—while feeling its full low-end power.
Q: What is the impedance of these headphones?
A: The Sennheiser HD 660S2 headphones have an impedance of 300 ohms.
Q: Do these headphones have a detachable cable?
A: Yes, the Sennheiser HD 660S2 headphones come with detachable cables.
Q: Are these headphones noise-cancelling?
A: These headphones offer environmental noise control, but they are not specifically noise-cancelling.
Q: What is the frequency response range of these Sennheiser headphones?
A: The Sennheiser HD 660S2 headphones have a frequency response of 8 Hz to 41,500 Hz.
Q: How long is the cable on these headphones?
A: The cable for these headphones is 1.8 meters long.
Q: Do these support Dolby Atmos?
A: Dolby atmos works through the device Any Headphones are plugged into. You don't need special Headphones according to dolbys site.
A: Check out the Atom 2 https://jdslabs.com/cart/
Q: Can I simply plug this into a Macbook Pro or iPad, or do I need a pre-amp?
A: Yes, you can plug the Sennheiser HD 660S2 headphones into a compatible MacBook Pro, as the 660S2 is not a USB device but connects via a 3.5mm jack, and compatible MacBooks (2021 or later) can drive high-impedance headphones like the 660S2 directly from their headphone jack. The MacBook's headphone jack can detect the headphone's impedance and adapt its output to provide sufficient power for high-fidelity sound.

Despite the HD 660S’s standing as one of the world’s popular audiophile headphones, some customers nevertheless wanted one very specific enhancement: even deeper bass. Because whether it’s a thunderous crescendo of timpani or the pulsating beat of electronic dance music, there is nothing like accurate, powerful sub bass to infuse your listening with drama. Audiophiles—and anyone looking for comfortable, non-fatiguing, high-end headphones—can now get even more impact and emotion from the HD 660S2. The headphone’s warm, relaxed tone is reflected by their timeless styling with elegant bronze accents. With its open-back design and outstanding comfort, the HD 660S2 is also destined to be a favorite for long listening sessions. This 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. Or experience the joy of discovering sonic details in recordings you’ve known for years—now underscored with more and deeper low end. Indeed, the standard-setter for extended listening has now become the standard-setter for extended bass as well. 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 coil offers a high magnetic force and electrical damping for a clean 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. Sound pressure at the lowest octaves has doubled. Now, you can feel the music more than ever before—with all the depth and weight that ultra-low frequencies invoke. The lowest A on the piano (27.5 Hz) or the pounding root note of a bass drum (45-60 Hz) are just as big, expansive, and imposing as if they were live. The unique combination of impactful bass combined with the warm tuning and smooth treble will be a revelation for audiophile listeners. It’s an even better way to lose yourself in comfortable, non-fatiguing, high-end sound—while feeling its full low-end power.

The HD 600 is the audio purist’s choice for reference playback. An instrument of Sennheiser’s passion for perfect sound, it is globally recognised as the standard for analytical high-fidelity listening - even 20-plus years after its release. The foundation of the extraordinarily clear sound of the HD 600 is its’ open acoustic design and the revolutionary transducer, which has been computer-optimized to reduce partial vibrations, which are responsible for a multitude of distortions.

Sennheiser HDB 630 Wireless Audiophile Headphones - High-Res Sound with Parametric EQ and Crossfeed, Bluetooth Headset with ANC and 60h Battery Life, Lightweight Design, Clear Calls - includes BTD 700. Flawless sound, no wires, and a battery that lasts for up to 60 hours. The Sennheiser HDB 630 lets outaketrueaudiophilesoundanywhere you go. Precision engineering brings out breathtaking clarity, a neutral tone, detailed mids, and a wide soundstage. Use aptX HD and aptX Adaptive Bluetooth® codecs from a high-resolution source such as Sennheiser’s BTD 700 Bluetooth® adapter or plug in via USBC for pure fidelity. The advanced parametric EQ lets you define frequency bands and filters as you please. Cross Fade balances classic tracks for better headphone listening while Active Noise Cancellation eliminates background noise while maintaining high-end audio quality.

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. The extremely precise yet non-fatiguing sound of the HD 660S2 delivers even more impact with extended sub bass. With an optimized surround, transducer airfl ow, and coil our engineers doubled the sound pressure at the lowest octaves. You can feel the lowest note on the piano (27.5 Hz) or the kick of the bass drum (45-60 Hz) as if you were there.
| Pros for Sennheiser - HD 660S2 Wired Over-the-Ear Headphones - Black | |||
|---|---|---|---|
| Sound Quality, Comfort, Bass, Open Back | Sound Quality | Sound Quality, Comfort, Battery Life, Connectivity, Included Accessories | There were no pros for this product— |
| Cons for Sennheiser - HD 660S2 Wired Over-the-Ear Headphones - Black | |||
| There were no cons for this product— | There were no cons for this product— | Design, Touch Controls | There were no cons for this product— |
Customers commend the HD 660S2 Wired Over-the-Ear Headphones for their immersive sound quality and upgraded bass. Users also appreciate the comfort of the headphones and the open-back design. Overall, the headphones are well-received for their audio performance and comfortable fit.
The vast majority of our reviews come from verified purchases. Reviews from customers may include My Best Buy members, employees, and Tech Insider Network members (as tagged). Select reviewers may receive discounted products, promotional considerations or entries into drawings for honest, helpful reviews.
Extremely good sound and much better lows than the S1. Great improvement
Dinglehump Posted
Using these headphones with a Topping DX3 Pro+ and a slightly tuned EQ I saw in a YouTube review. They sound very good and very open. Zero distortion in my usage. Very nice overall
Jeffrey Posted
The SENNHEISER HD 660 S2 is exactly what was missing from the previous iteration by including low-end bass, adding a much needed punch to an already well performing set of headphones. It delivers exceptionally on all fronts, including music, gaming, movies, and even conference calls. The one thing I heavily appreciate from the 660 S2 is how the headphones are open back, which while it adds to an incredible sound delivery, they can also act as a makeshift stereo system, allowing others to also listen in to whatever it is your're listening to. If you can grab these on sale, they are easily one of the best headphones for everyday usage.
JuanG Posted