Sennheiser HD 660S2: The Fan-Favorite Open-Back Series is Back in Business!

Sennheiser HD 660S2

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The Sennheiser 600 series always had a soft spot in the heart of audiophiles. All the models offered great reference-level detail and outstanding overall sound performance. 

But with the Sennheiser HD 660S2, things got amped up a little. It is the latest addition to the 600 series and comes with a banger frequency response.

Sennheiser made the HD 660S2 offer to offer a more engaging frequency response. The headset has enhanced sub-bass tuning. 

Sennheiser HD 660S2
Source: Sennheiser

The new headset also provides a warm bass and smooth overall treble performance. Sennheiser made all of this possible through the refined voice coil and an improved transducer airflow.

By reducing the weight of the Sennheiser HD 660S2, the audio specialist was able to amp up the impulse response. 

That, according to Sennheiser, will bring “hyper-realistic textures to the forefront of any performance reproduction.”

Sennheiser HD 660S2
Source: Sennheiser

So, how does it compare with the HD 660S? The overall experience with the Sennheiser HD 660S2 is much smoother and warmer in comparison. 

And that has been made possible with the tuning that reduces the distances between the select troughs and peaks.

The overall impedance of the HD 660S2 matches the HD 650 and HD 600. That is, the impedance is at an audiophile-friendly level, which is 300 ohms. 

Sennheiser HD 660S2
Source: Sennheiser

But it is still more than enough to let you enjoy “punchy dynamics and impressively low distortion.” Besides, the overall build quality of the Sennheiser HD 660S2 is pretty impressive. 

Designed in Germany and manufactured in Ireland, the headset comes with cushy headband padding and plush earpads. Through the unique, Sennheiser was able to revise the placement of the 300-ohm transducers.

In the Sennheiser HD 660S2, the transducers are now at a more optimal distance from the ears. This placement will result in a more spacious soundstage and give you plenty of detail from the music.

The transducer of the HD 660S2 drops the resonant frequency to 70 Hz from 110 Hz. That will eventually allow you to get the hefty drum kick sound from the music.

Sennheiser HD 660S2
Source: Sennheiser

On the other hand, the mesh grilles on the outside are designed to manage airflow at the ideal impedance. 

The Sennheiser HD 660S2 also comes with a user-detachable cable, which terminates to a 4.4 mm balanced stereo and 6.3 mm single-ended stereo jack plugs. Basically, things are looking good for the new headset.

In fact, Sennheiser is so proud of its HD 660S2 that it states that the headphones will offer what most listeners want to hear from the predecessors of the HD series. According to the audio specialist, the HD 660S2 will enable you to hear precision and power like no other.

Slava is a man of mystery and no-one seems to know exactly where he is at any point in time. When he isn't enjoying writing about all things audio and technical he can be found researching his next project of interest. The man never rests.

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