Customer reviews from Sennheiser
Sennheiser - Refurbished Excellent - HD 660S2 Wired Over-the-Ear Headphones - Black
Average customer rating
4.7
(18 Reviews)
Rating breakdown 18 reviews
5 Stars
15
4 Stars
2
3 Stars
0
2 Stars
1
1 Star
0
88%of customers recommend this product.
(
7 out of
8)
Customer Reviews for Sennheiser - Refurbished Excellent - HD 660S2 Wired Over-the-Ear Headphones - Black
Customer Rating
5
Best one so far
on February 2, 2024
Posted by: LilStun
I went to these from some DT 990 Pro's 250ohm. and lemme tell you something. its been about 2 months but im still sold that these will be my forever headphones. I have never felt that way about headphones. They sound FULL, very full. Super detailed and clean, and pretty good sub bass. I have them paired with a FiiO k5 pro
Written by a customer while visiting Sennheiser
Customer Rating
5
Perfect Daily Driver
on February 26, 2023
Posted by: Adrian
from Gaithersburg, Maryland, United States
My set is only a week old and still breaking in, but with around 50 hours of listening, I'm finding the HD 660 S2 to be an easy favorite in my headphone collection. There has been a lot of kerfuffle about these being less neutral than the venerable HD 600, which to my ears is true, and I like the differences. This is an opinionated set! They have a slightly narrow soundstage but with more "vertical" separation than you'd expect if that makes sense, which create a slightly intimate setting (much moreso than e.g. AKG K701) with noticeable frequency band separation. This actually pulls some presence out of a lot of the electronic music I listen to (mostly ambient like Hollan Holmes and 36), but is *incredibly* flattering to acoustic material. Old Paul Simon tracks sound like a meticulously recorded Hillary Hahn recital out of nowhere. By being freed from studio monitor duties, this set of headphones has turned my music library into buried treasure, and it's been a lot of fun going through it.
Also, the reviews that list comfort as the first thing you notice aren't kidding. I apparently have an enormous head that nothing fits or feels good on, and these things feel almost therapeutic over 4-5 hours of listening. They aren't that heavy, the build quality is great, the fabrics are excellent (also yay fabric), and the result is a nicely convincing amount of pressure over a widely distributed area through nice materials and they just feel excellent. Paired with the open-back design, they are an extremely relaxing piece of kit.
I'd recommend these to anyone, with the hopefully expected reminder that they are the real thing and as such absolutely do need a real break-in period of proper audio exercise both for the drivers and for the headband and pads.
Written by a customer while visiting Sennheiser
Customer Rating
5
WOW
on March 4, 2023
Posted by: Jayson
from San Francisco, California, United States
These are the most well made and comfortable headphones ive ever used. Honestly unmatched in sound balance & quality, although I do have some issue w getting it as loud as Id like, but that could be due to my interface. all in all for comfort & sound I give these a 10/10
Written by a customer while visiting Sennheiser
Customer Rating
5
Way better than expected
on April 7, 2025
Posted by: DHL
from Pismo Beach CA
Gender:Male
I bought the 660S2 HP expecting mid level performance in this day and age of 3K to 6K top of the line HP. Was very surprised when I A/B'd this set with Hifiman Susvaras. Bass response was very good; attack and decay was better in the Sennheisers vs the Susvara. The Sennheisers were considerably warmer sounding than the Susvara, but in a musical way, not muddy or smearing. The Susvara has a bit more "air" and inner detail, but not 6K worth. I did not experience a broad sound field with either HP. Subtle detail like the bells in John Klemmers Touch were a bit more evident in the Susvara but still very much present in the 660s. Driving the Sennheisers was considerably easier than the Susvaras as has been noted elsewhere, but cabling is less critical with the more sensitive Sennheiser's higher 300 ohm impedance; wire gage makes less of a difference if you have longer wire runs as opposed to the low sensitivity 60 ohm Susvara. I found I had to crank my class A HP amp up full volume with the Susvara leaving little headroom. The Sennheisers were easily driven with that amp with plenty of headroom. I generally I was very surprised at how good the Sennhesiers are, and they are probably 80 to 90% of the performance of the Hifiman product, some may find them overall better.
I would recommend this to a friend!
Written by a customer while visiting Sennheiser
Customer Rating
5
Supreme Quality
on May 5, 2025
Posted by: jwestbrook
I am very happy with this purchase. Supremely comfortable to wear, very nice/quality engineering produces a high fidelity sound experience... I particularly appreciate Sennheiser following up with the sound samples via email, whereby I received a 'guided tour' of the capabilities built into these headphones... Supreme quality - excellent sound reproduction - no regrets, would buy again...
Written by a customer while visiting Sennheiser
Customer Rating
5
Awesome upgrade after 20y
on October 20, 2023
Posted by: jorcap
from Salt Lake, Utah
Gender:Male
Sound is superb. A great upgrade from HD 650. Not as amplifier dependant. Not as colored as 650. Just as detailed & vivid but more neutral overall, plus subbass which is lacking in 650.
I would recommend this to a friend!
Written by a customer while visiting Sennheiser
Customer Rating
4
My HD 660S2 experience
on February 26, 2023
Posted by: Adam
from Waterloo, Illinois, United States
So far, I love these headphones. I listen to music, obviously and they sound incredible. It almost feels like it engulfs me and transports me to a happier place. I also game a lot, and they still sound incredible, the low thuds of artillery fire and the high pitches poorly oiled machinery moving through fields, it sounds like I'm really there at least. (Though maybe not the greatest place to be pulled into) With all my praise I am currently giving these headphones, you may wonder why I felt like I had to give it 9 stars. They are tight, they like to squeeze my head and makes it hard to have on for extended periods. I will admit they are looser than the HD650's out of the box, still tight. However I am the type that struggles to find a hat that fits in stores, so tight headphones are to be expected. All in all, I highly recommend these headphones.
Written by a customer while visiting Sennheiser
Customer Rating
2
Not the upgrade it is purported to be
on January 22, 2024
Posted by: listener6x0
from Pennsylvania
Gender:Male
Touted as the upgrade to the HD 650, but it's more like the upgrade to the HD 58X from Drop.
Doesn't have any of the midrange magic of the 6 series, has meaningfully brighter and harsher treble, and is significantly more expensive. Looks incredible (love the colorway) but sonically it's a miss for me across the board.
No, I would not recommend this to a friend.
Written by a customer while visiting Sennheiser