[KaiFi]

I bought another pair and I'm glad I did because these are excellent. I've had Sennheisers before; the HD 598 was my first hi-fi headphone. But I moved to closed-backs because of the loud environment I live in and hadn't really looked back to Sennheiser since, though when these came out I was really curious to try them. I've heard so many things about the sound of these and I don't see how anyone couldn't like them. They're like the perfect neutral "Goldilocks" sound to me (yet not dull at all). They sound good with every genre I throw at it (can't say the same for any of the other headphones I've tried recently, though the Sundara came closest to having that "one-size fits all" sound). Been listening with the balanced cable from my Zen DAC V2. The pads are not the most comfortable and dig into my face a bit, but I also have some leather/hybrid pads from Drop that I bought a while ago for the 58X that I no longer own. So I'm gonna play around with those.

I can't imagine liking the other Sennheisers in this series better than these; to me this is just about perfect, sound-wise. The only problem is I still don't have many opportunities to really enjoy open-backs!

(I swapped out the balanced and unbalanced cable several times and haven't had any sound cut out, so I think this pair is working just fine).

 

[alexeyi]

I bought another pair and I'm glad I did because these are excellent. I've had Sennheisers before; the HD 598 was my first hi-fi headphone. But I moved to closed-backs because of the loud environment I live in and hadn't really looked back to Sennheiser since, though when these came out I was really curious to try them. I've heard so many things about the sound of these and I don't see how anyone couldn't like them. They're like the perfect neutral "Goldilocks" sound to me (yet not dull at all). They sound good with every genre I throw at it (can't say the same for any of the other headphones I've tried recently, though the Sundara came closest to having that "one-size fits all" sound). Been listening with the balanced cable from my Zen DAC V2. The pads are not the most comfortable and dig into my face a bit, but I also have some leather/hybrid pads from Drop that I bought a while ago for the 58X that I no longer own. So I'm gonna play around with those.

I can't imagine liking the other Sennheisers in this series better than these; to me this is just about perfect, sound-wise. The only problem is I still don't have many opportunities to really enjoy open-backs!

(I swapped out the balanced and unbalanced cable several times and haven't had any sound cut out, so I think this pair is working just fine).

Well, enjoy your headphones. Dekoni offers multiple variants of pads for HD6x series, so if you find the stocks one uncomfortable, you can always go for different materials.

 

[Tripokaridos]

I bought another pair and I'm glad I did because these are excellent. I've had Sennheisers before; the HD 598 was my first hi-fi headphone. But I moved to closed-backs because of the loud environment I live in and hadn't really looked back to Sennheiser since, though when these came out I was really curious to try them. I've heard so many things about the sound of these and I don't see how anyone couldn't like them. They're like the perfect neutral "Goldilocks" sound to me (yet not dull at all). They sound good with every genre I throw at it (can't say the same for any of the other headphones I've tried recently, though the Sundara came closest to having that "one-size fits all" sound). Been listening with the balanced cable from my Zen DAC V2. The pads are not the most comfortable and dig into my face a bit, but I also have some leather/hybrid pads from Drop that I bought a while ago for the 58X that I no longer own. So I'm gonna play around with those.

I can't imagine liking the other Sennheisers in this series better than these; to me this is just about perfect, sound-wise. The only problem is I still don't have many opportunities to really enjoy open-backs!

(I swapped out the balanced and unbalanced cable several times and haven't had any sound cut out, so I think this pair is working just fine).

To me also the HD 660s are the best headphone i have ever had ( for my taste because its all about taste) but honestly i like and keep all HD 6 line .

 

[Tripokaridos]

Well, enjoy your headphones. Dekoni offers multiple variants of pads for HD6x series, so if you find the stocks one uncomfortable, you can always go for different materials.

I have tried most of the pads for HD 6 line , Dekoni, Drop, Brainwavz with modded ring, Yaxi pads, Amazon china fake pads , i have NOT tried ZMF ( i have posted photos and my xp about them ) .
All of them they DO change the sound ( personaly i didnt like it ) but some people do .

About Pads all of the aftermarket pads that i tried doesnt have the Hybrid Velour outside and leatherette inside the ring that original ones have , also all of them didn use the shame Velour material , some are using leather , alcantara , suede, etch etch . Also all of them had Stitches in front of them Pad , original pads u cant see any stitching ...Its under the plastic ring ... All an all in my opinion Original pads are way better in every way .

The stitching aftermarket vs the OLD before 21 pads ....


These are the Pre 21 pads , VS the 21 Pads ... The Old ones have different colour Velour and they was softer , the new one was stiffer and taller.

And I bought another one Original Pad Today and its better than also Pre 21 pad and after 21 pad ( i dont know why ) But they are for sure Softer ( like the old pre 21 pads soft ... and the Velour feels more premium in the hand softer , also they are taller than both pre 21 pad and 21 pad that i have . So it looks like there was some changes between 21 to 22 and everything that is 2022 i guess it must be like those that i got today ...
About the sound ? They sound identical ( maybe a little bit more clear ) but again they are to new .

Also the Foam inside the Pre 2021 pads is different ... The old foam was this ...


So in my opinion , my recommendation are the New 2022 pads , 2021 pads and after have all of them Clear Ring , not the Black one also they are more rounded and taller . About 2022 vs 2021 pads ... thats a hard one because i really dont know why they are different ... like i said it must be a part between the changes that they make . I guess every new 2022 pad would feel , look and have the shape of the ones that i got Today .

 

[PieroBG]

The new zmf pads should be interesting in terms of sound and longevity :0

Out of curiosity I tried the ZMF pad in perforated lambskin and I must say that I am delighted to have done so because the 660s seems to have transformed into a beautiful headphone with a wider soundstage, more defined and brilliant sound making them headphones also suitable for very rock music. more than they were before with their beautiful mids but a little too controlled .. obviously according to my tastes.

 

[piakoB]

Had some extra money laying around and decided to pickup a pair of HD660S. Am probably going to sell my Ananda, Sundara and SR225x after doing comparisons this afternoon. I was using my Grado for symphonic music because it really can attain full driver excursion and give you that punch when the orchestra strikes all at the same time loudly. 660s can't do that fully the same as the Grados but get at least half the way there. Adittionally the grados had a harshness and ring in the high treble when listening to older symphonic and opera recordings because of the nature of the recording technology at the time. The 660s seem to eliminate this hiss on older symphonic recordings which is a good listening comfort plus. I was using the Anandas for mostly pop and jazz and while they have a better brilliance and resolution compared to the 660s I would say the sennheiser's are about 80 percent there compared to the Ananda especially in detail and focus. And the final reason I'm probably selling the others is that the 660s can do relatively good metal, rock and electric guitar music where the Anandas for this genre just sounded bad (too quick of a release of notes, harsh highs, unfavorable tonality). The 660s seem to be a jack of all trades and I'm really super happy I got these. Everything I've thrown at them is overwhelmingly positive.

 

[KaiFi]

^I feel the same way. They are a great all-rounder and sound good with every genre I listen to.

 

[Tripokaridos]

Had some extra money laying around and decided to pickup a pair of HD660S. Am probably going to sell my Ananda, Sundara and SR225x after doing comparisons this afternoon. I was using my Grado for symphonic music because it really can attain full driver excursion and give you that punch when the orchestra strikes all at the same time loudly. 660s can't do that fully the same as the Grados but get at least half the way there. Adittionally the grados had a harshness and ring in the high treble when listening to older symphonic and opera recordings because of the nature of the recording technology at the time. The 660s seem to eliminate this hiss on older symphonic recordings which is a good listening comfort plus. I was using the Anandas for mostly pop and jazz and while they have a better brilliance and resolution compared to the 660s I would say the sennheiser's are about 80 percent there compared to the Ananda especially in detail and focus. And the final reason I'm probably selling the others is that the 660s can do relatively good metal, rock and electric guitar music where the Anandas for this genre just sounded bad (too quick of a release of notes, harsh highs, unfavorable tonality). The 660s seem to be a jack of all trades and I'm really super happy I got these. Everything I've thrown at them is overwhelmingly positive.

To me HD660s like most people say they are the best all arounders , They are almost perfect on imaging ,vocals, timbre , smoothness and good to very good in everything else . And if u consider the Light Weight , good Quality control, Last forever , and u can find parts easy then yeah its hard not to keep them.
But , in my opinion I always keep something different for example i sold some Beyers , Focals, Hifimans and now i have again the Sundara the reason is that they sound good also , and enough different for me to keep them , for example i prefer listening Movies with Sundara than my HD 6 line . Also gaming Is nice with DT1990 and Sundara (660s are ok for gaming if u care about directional sound) .

I never had a Grado Headphone and from what i have read , i would also keep one of them for sure. If i was u and have to sell one of them ... then Sundara or Ananda see what u like more between those and keep one of them . (for me sell Anandas and keep Sundara )

 

[Tripokaridos]

Out of curiosity I tried the ZMF pad in perforated lambskin and I must say that I am delighted to have done so because the 660s seems to have transformed into a beautiful headphone with a wider soundstage, more defined and brilliant sound making them headphones also suitable for very rock music. more than they were before with their beautiful mids but a little too controlled .. obviously according to my tastes.

Can u share some photos of them ? outside and inside the Ring ? I never seen any of those ZMF pads .

 

[10000days]

What I like about the HD660s is that they're the only "mid-fi" Sennheiser headphones that are smooth both in the lower mids and upper mids/lower treble region. HD600 and HD6XX are smooth only in the low mids - upper mids are quite shouty and grainy, HD58X and HD598 are, in my opinion, mediocre in the lower treble area, HD560s is shouty and harsh all around, also heavily congested, like a heavily EQd HD598, but that's another story.

The HD660s is a strange headphone. Sometimes they can sound rather unimpressive when auditioned on their own, but when compared directly to rival pairs, you realize they actually have great control and detail, it's just obscured by their inoffensive tuning. I A / B tested them against the Ananda and concluded these are the better pair (for me), both slightly EQd closer to the Harman Curve. On the Sennheiser the mids don't have any ringing, there's zero shoutiness there, and zero sibilance in the treble - extremely neat, the timbre is about perfect, the soundstage is smaller but far more coherent, even their decay and instrument separation are nearly as good (keep in mind this is a dynamic driver), they just provide a better experience than the Anandas 75% of the time.
However, they're not devoid of flaws: sub bass quality and quantity is not as strong (although I'd argue midbass and upper bass are better textured on HD660s), and the treble sounds thin to my ears, as if all sparkly sounds are extremely minuscule, fragile and lost in the mix - which in turn can make them very pleasant sounding for the treble sensitives.

I'm no big fan of Sennheiser, I guess I kinda like the HD598, I can't stand the old HD6-- series - so narrow and lumpy, and the HD560s is my least favorite audiophile headphone of all time, but I consider the HD660s a near masterpiece.

 

[Angel III]

I had HD58X and HD660 and kept the HD650.
In my opinion these headphones sound good in rock or metal only when the tracks are well recorded. In classical, jazz and country music is where in my opinion the Sennheiser HD family excels. The HD58X stands out in the double bass and viola.
The HD650 is the one that lets you pick out more details in a track, due to it having a better spaced soundstage.
When I bought the Austrian Audio Hi-X65 I sold the HD660s. The Hi-X65 is in the same tone as the HD660, but the latter does not compete in any way in the sub-bass and bass and in the soundstage. If you like rock and metal the Hi-X65 is an impressive headphone (but also in other musical genres).

I specify that I always use the equalizer in all my headphones.

 

[GearMe]

I had HD58X and HD660 and kept the HD650.
In my opinion these headphones sound good in rock or metal only when the tracks are well recorded. In classical, jazz and country music is where in my opinion the Sennheiser HD family excels. The HD58X stands out in the double bass and viola.
The HD650 is the one that lets you pick out more details in a track, due to it having a better spaced soundstage.
When I bought the Austrian Audio Hi-X65 I sold the HD660s. The Hi-X65 is in the same tone as the HD660, but the latter does not compete in any way in the sub-bass and bass and in the soundstage. If you like rock and metal the Hi-X65 is an impressive headphone (but also in other musical genres).

I specify that I always use the equalizer in all my headphones.

Interesting!

Sounds like the X65 is worth a listen...just ordered some.

Thomann has them for $359 all-in including UPS Express shipping to the US. Should be here by Monday

 

[Angel III]

Interesting!

Sounds like the X65 is worth a listen...just ordered some.

Thomann has them for $359 all-in including UPS Express shipping to the US. Should be here by Monday

Good! Hope you can compare them to the Sennheiser. Tune them well with an equalizer and use a good quality dac amp.

 

[JM]

Check this out. I decided to buy another pair of 660s', I've had 3 pairs now. One from 2018, 2020 and now 2022. I purchased directly from Sennheiser.

'Made in Ireland'. That was a little surprising considering I thought all manufacturing had moved to Romania. Does anyone know what's up with that?

Also, I had an unopened 1.4m short cable (art. no. 570679) to use with them and had the hardest time getting the male connectors into the female part of the headphones on both cups. I practically had to force them in.

 

[gimmeheadroom]

They abandoned the Romanian operation recently and moved production back to Ireland and Germany.

P.S. to say the HD 600 is shouty is disconnected from reality They're among the smoothest dynamic headphones ever made.