The new HD 660 S lets you enjoy sophisticated audiophile sound in even more listening situations. The successor of the legendary HD 650 excels with the improved performance of its new transducer design. Thanks to its lower impedance, it delivers reference-class sound also when connected to hi-res mobile players, thus offering much greater versatility. The HD 660 S is an elegantly designed piece of high-quality engineering that indulges the demanding listener with aural precision and great wearing comfort.
Sound for the passionate music enthusiast
Made for the demanding listener, the HD 660 S surpasses the exceptional performance of its predecessor, the legendary HD 650. With a crisp bass, excellent mid-frequency response, and a gentle, pleasantly natural treble, the HD 660 S has an expressiveness that immerses you in every emotion and nuance of music. Still, it always stays exceptionally accurate and transparent.
Cutting-edge Sennheiser technology
The HD 660 S features a new transducer design developed by Sennheiser. This results in improved control of the diaphragm movements thanks to a specially manufactured precision stainless steel fabric, which is adapted to the contour of the diaphragm. Extremely light aluminum voice coils ensure the highest impulse fidelity. The transducers are carefully selected and paired by hand to ensure consistently narrow (±1 dB) tolerances.
The HD 660 S has been created to enjoy music in supreme quality and from many different audio sources. Thanks to its low impedance it also offers reference-class fidelity with hi-res mobile players. Naturally, the HD 660 S reveals its full potential when it is connected to the balanced outputs of a dedicated headphone amplifier such as the HDV 820 or to the balanced output of a mobile digital audio player. Accordingly, it comes with a choice of cables for just about any occasion. All cables are made of highly conductive OFC copper, featuring very low handling noise and sturdy para-aramid reinforcement.
Designed for high-end comfort
Everything about the HD 660 S makes listening a pure pleasure – not least its strong yet lightweight open construction. The elliptical ear cups are shaped to follow the anatomy of the ear, while thick padding on the headband and the replaceable ear cushions guarantee hours and hours of listening in supreme comfort.
The look of sophistication
The pure and effortless sound of the HD 660 S is reflected in its new matte black and anthracite design. It is a high-end aesthetic that embraces both timeless elegance and contemporary style – uncompromising in its craftsmanship, like everything about the HD 660 S.
Don't expect these headphones to work well with all types of music or poor recordings, they are just like the HD600s "very fussy" With the right equipment and the right recordings they are stunning. I would recommend a good listen to them before buying them.
I have a HD598 with me for a well over a year and to my ears it was the best sounding cans among my headphone collection. Until. These cans came and after one hour of listening, man! I could never be wrong. These cans fit for those who wanted to find what genre of music is for him and if you are an aspiring singer, it could determine what genre should be for you after you hear your own recording. Well, even on smartphone recording. The only one thing I wish is they should added a 1.2m long straight cable with a 3.5 termination. Perfect also for Eurobeat or EDM genre.
At quick glance, the HD 660 S may look like a modified HD 650 with HD 700 drivers transplanted inside of it, but that is where the similarities end. The HD 660 S offers the low-level detail characteristics that make the HD 800 so highly coveted among TOTL- and kilobuck-seeking audiophiles but with the HD 600's naturalness. In other words, remove the treble peaks that plague the HD 700 and, to a lesser degree, the HD 800, and retain the resolution of the HD 800 and you have the HD 660 S. Sennheiser has been removing the HD 650 from their site, and that alone suggests they have deep confidence in this new mainstream audiophile flagship product. I concur without equivocation, as I can see the HD 660 S easily inheriting the HD 650's throne to become the new go-to headphone among the community at large. In addition, I could see many of those who were less than thrilled with the HD 800's clinical sound (slightly withdrawn upper midrange and slightly boosted mid treble) going in ravenous droves after the HD 660 S. I really had to grasp at straws to find something negative to comment about these, and the only thing I could state is perhaps the retro looks may seen worn out or uninspired, but I personally am fond of this more classic, understated Sennheiser look over the gaudy Cyberman-like, space-age vibe of the HD 800 and HD 700. This is your atypical all-arounder with heightened technical abilities. Fast or slow, brash Bon Jovi or binotonous Beethoven, Sennheiser nailed this release with world-class expertise. Arguably, you could not do any better $999 and below. Amped and unamped, the HD 660 S is a force to be reckoned with, well-deserving of and highly recommended for a spot in the headphone stables of audiophiles seasoned and budding.