Siegfried: Time to say adieu MM. I thank you for helping me see the dark light but keep my optimism. I have enjoyed my time with you again. It has been a while. I ask you to wrap up your thoughts about the Sennheiser HD 660S2. I now look you in the eye and say Prost and Zum Wohl mein Freund!

Sennheiser HD 660S2 review - SoundGuys

The 660S2 has slightly better technicalities, it is a bit more tight, layered, better defined and controlled but also more drier and not as full bodied and visceral as the 109 PRO. Overall, the HD 660S2 are better suited for most modern genres. At the same time, I cannot overlook the price tag, which is nearly twice that of the HD 6XX Drop variant of the HD 650. The performance upgrade hardly justifies such a massive price gap, so the HD 650/6XX still remain as good an option as ever. Technical Specifications As a whole the timbre on the 660S2 is more natural and realistic throughout the whole frequency range, this is a more serious sounding headphone when the 109 PRO is more youthful, fun, dancing and partying. The surround is now more compliant, too, dropping the resonant frequency to 70 Hz. Considerable effort

As the big focus of this review is on the comparison with the other Sennheiser headphones and the amplifier synergy, we’ll keep this part to the point. Testing was done with a series of amplifiers, using the Musician Audio Aquarius and EarMen ST-AMP as DAC, streaming music from Tidal via ROON on my laptop. For the direct comparisons I used the Cayin Audio HA-3A tube headphone amplifier, as it has an impedance selector, and it allows to connect 2 headphones in balanced mode at the same time. All testing was done in balanced mode, unless specified otherwise. The headphone scales very well and will highlight higher quality electronics but up to a certain point as it cannot eventually compete with really high end headphones, like the Meze Elite and HiFiMan Susvara, in scaling potential.

Sennheiser HD 660 S2 headphones are a sound upgrade to a Sennheiser HD 660 S2 headphones are a sound upgrade to a

BTW here the playlist I use for understanding HPs for review purposes. These are the songs I listen to most due to the quality of the recording in a lot of cases as well as how much I enjoy the songs: The 660S2 is drawing me to everything. In a similar way the ZMF Caldera does. Nothing is missing in my opinion. Nothing is too much. The timbre is there. The musicality is there. It is detailed. The bass is there. There is not an annoying V shape. 80% of the music is in the mid-range and the mid-range of the 660S2 is exactly what it should be. The bass and treble act as accoutrements. The top and bottom frequencies are super well integrated with the mids. They add color to the mids. Not too much and not too little. balanced, natural reproduction. Recognized as benchmarks for neutral audiophile sound, the HD 600, HDThis is a tuning with plenty of bass and mid-bass that favors the fun and enjoyment factor rather than actual tonal accuracy.

Sennheiser HD 660S2 | Headphone Reviews and Discussion - Head Sennheiser HD 660S2 | Headphone Reviews and Discussion - Head

Outside the Sennheiser ecosystem, the HD660S2 is an undeniably excellent sounding headphone with supreme technicalities and a balanced, realistic tuning that offers plenty of musicality and emotional involvement and as such it directly compares with similar or slightly more expensive headphones like the HiFiMan Ananda Stealth or the Meze 109 PRO. I listen to jazz more than anything else. Trio and modal jazz to be more specific. My playlist for understanding gear does not have a lot of jazz in it since I want to hear numerous instruments happening in the same song and more bass and treble and of course vocals. Unfortunately, the price is higher than I consider “apt.” The MSRP is exaggerated for a product that is a slight upgrade over the last model – primarily offering improvement in the bass for existing HD 600 and HD 650 owners.

Stock Cables

Voices get always highlighted and projected in front of the listener who additionally feels very closely positioned to the performers, a type of tuning that might work very well for a lot of people but others might find it fatiguing and tiring in the long run. When looking at the HD 660S2’s frequency response, you can clearly see the elevation in the bass region, but also the treble section was tweaked a little upwards (except for the lower dip from 3-5k). It makes the HD 660S2 have more presence as well as more energy on top, but it never feels forced or out of balance. My ears certainly dig this typical tuning. Still the HD660S fairs better than the rest of the family with the more spacious and airy soundstage that is slightly wider and more open while it places the listener in a more realistic and proportional distance from the performers. Male voices are closer on S2. The tonality/naturalness of male voices on 600 and S2 are both excellent. I like the timbre on both. The S2 notes are a tiny bit more rounded than the 600. I would attribute this to the wider stage of the S2. It is not that you can't listen to classical music but the instruments sound slightly out of tune and emphasized compared to, the already slightly colored, 660S2 which comparatively is more in-tune sounding.