Sennheiser HiRes Audiophile Headphone (HD 660 S)

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Interestingly, despite the fact that I don’t feel the notes flying a few meters from me, I can clearly hear the angle at which they are emitted, a good sign that the holography is in effect. Schiit Wyrd > USB Version 5 Schiit Yggdrasil > Dragon Inspire IHA-1 > Sylvania Bad Boy 6SN7 + Philips Metal Base GZ34) So again I’ll state that the “handshake” given to me from Sennheiser was firm and filled with confidence, which is exactly what I’ve come to expect from Sennheiser. When it comes to sound density, all 3 models are effortless. The sensation of a meaty sound, full of substance and density is best present on the HD 650 and HD 660 S. With this recording the perspective difference between the two headphones is clear. The 600 sounds more distant, while with the 660S we are virtually in the middle of the stage. It's not very realistic, but the introspection in the harmonic structure of the instruments is exciting. The 660S has the best harmonic resolution: yes, this time the 600 loses harmonic content in comparison.

Anyway, what is really important is that sonically HD 660S is quite different from the HD 700, which for me is a good thing.

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TheHD 660 S2's upgrades look like sensible ones, butSennheiser nevertheless has a big task on its hands as it tries to satisfying the fussiest demographic of music lovers. Sennheiser HD600 and HD650 have both been emblems of quality in the audiophile world for almost ten years now, with HD660S coming to change that and bring a new headphone to the table. We're having a look into what it brings to the table, and into how it changes the headphones that are already loved by thousand of people from all over the world. The 660s is a fine-sounding headphone. I can listen to it and enjoy it for extended periods of time. Nonetheless, this sound section is a bit shorter than I often do because I think the big story with the 660s is found in the…

I’ve had a pair of HD 580 Precisions for around 25 years now, which are widely considered to be a very slightly inferior cousin to the HD 600 and HD 650. If, like me, you were expecting a subtle change in sound between these original models and the HD 660 S, then you’re in for a surprise – the difference is dramatic. The lower-midrange of the HD660S sets it quite a bit apart from the HD650, to my ears – but more on that later. It is decently represented without slipping into the overly warm category. Make no mistake, I’d still classify this as a bit of a warm headphone (all things considered) but it certainly has less emphasis in the region than I expected. I found male vocals to do really quite well, and found the chugging effect of distorted electric guitars to have ample body and weight to them. Now That We’re Dead by Metallica is a good example of both these factors in play, with the bite of the rhythm guitars being in full effect. Now, HD660S is not a portable headphone. Even trying to consider them to be one is wrong. We did take them on a little adventure in the Izvor Park in Bucharest to test this, but they still are not quite that portable, they would probably fit best with your favorite desktop and armchair setup. The specs of the HD 660 S brag a SPL top-end of 104dB and a less than 0.04% distortion using 1kHz at 100dB. These controlled sound tests are certainly reasonable bench test but I like to just get down to the real deal and run the “Butch Vig SPL test” with some Nirvana. The HD 660 S performed quite well. Even at intense levels, this headphone remained tight and unflappable. It was only at the very top end that I could hear a little bit of distortion. SoundstageThe Sennheiser HD 660 S are comfortable, have a great soundstage and a non-fatiguing combination of clarity and rich tone. For the HD660 S2, Sennheiser revised the coil of the S2, and it now matches the 300-ohm impedance of the legendary HD 600 & HD 650. This new coil also provides higher magnetic force and electrical dampening for cleaner impulse response. The surround – according to Sennheiser – is now more compliant too, dropping the resonant frequency to 70 Hz . Considerable effort also went into optimizing the airflow around the transducer. There’s more sensitivity over the entire frequency spectrum because the magnet´s air gap works more efficiently now. Taken together, these measures result in even greater precision, speed, and resolution — with double the sound pressure at the lowest frequencies. In this, and the following series of photos, the HD 600 is at left, the HD 650 at center, and the HD 660S is to the right.