Sennheiser HD 660 S Open, Dynamic Lightweight Circumaural Headphones with Low Impedence and Improved Transducer Design for Audiophiles, Black

There were several reasons to add these "Sennheiser HD 660S Over-Ear Open Dynamic Headphones - Black" to a small but growing personal mini-collection.The packaging is essentially to expectations, card sleeve enclosing a solid box in which are the 'phones, cables and data booklet. The only issue is that the box is a VERY TIGHT fit in the sleeve and difficult to remove without damage to the sleeve, not that all will care about that! Once extracted, a thick lump of dense foam packaging within the box pushed its two sections outwards and the cause of the difficulty.Included cables are a 4.4mm balanced and a 3.5mm unbalanced, both 3m long and rubberized. There is an option for a balanced XLR cable should that ever be needed. As best known, coiled versions are not available as potential alternatives to those provided as they have a reputation for kinking. Rather than the gold-plated brass headphone adapter most manufacturers include, there is a short adapter cable ending in a plastic-bodied socket. The connectors linking with the earpieces are not obviously keyed other than being labelled L and R, respectively, on the outside.The earpieces lack any obvious labelling for side (L or R). The cable connectors are marked but the lettering is small, black on black and barely rise beyond the general surface. The key is the gold S logo on each unit which should be oriented to the rear.The headband is the expected thick, broad band with deep velour-covered foam pads to either side of centre with sufficient adjustment for different head sizes, hairstyles etc. The ear-pads are also velour-covered which should be longer-lasting than the 'leather' found on lesser models and that usually need replacing within two years; these should last several years. Both sets of padding are sufficiently thick and comfortable.While immediately comfortable to wear, and likely to be just as comfortable after several hours, they are quite lightweight as plastics are used extensively, a significant surprise at the price paid. Were construction of carbon-fibre, glass-fibre or a honeycomb composite as used in the aviation industry (subject to suitability); the weight would be similar but perception of construction standards would probably be higher. Regardless, construction is to an adequately high standard although a hard case may be desirable should they need to be transported between home and studio or between venues; the 'phones are not designed to fold so is likely to be large and preferably internally sculpted to fit. At home, a suitable headphone stand (a polystyrene head?) could be a worthwhile addition.Designed for audiophile, professional studio or monitoring purposes the HD660s' perfectly flat mid-range and lower-treble - the portion of the audio range most relevant when monitoring or producing - is outstanding and probably exceeds almost everything within their price range. Overall frequency response is quoted as 9 Hz to 41500 kHz but without a specified variation at the extremes. Sub-bass performance out-of-the box is less impressive.The HD660s generally requires a headphone amplifier and that is how it will be later used; a burn-in period using a radio's headphone socket as a source will follow almost immediately with the 'phones buried under a pile of cushions to deaden the leaking sound over the minimum of two or three days' continuous play it involves - it isn't necessary to listen, especially if in a bedroom at night!The amplifier owned offers two functions dedicated to an older Sennheiser model that is now manufactured by another company and rebranded. That model has widely recognized performance issues that the amp can resolve. Although not specifically intended to support them, it was suggested by an independent professional audio lab that there is a shortlist of Sennheiser models that each benefit when partnered with the amp; the HD660s is one, supported not equally but even better! That information was previously unknown.Having purchased the amp to use with other owned headphones, it was initially thought not to be fully functional as its benefits were not audible with either. Questions were raised with the manufacturer and some clarification followed but additional questions were raised but not yet resolved. Once support for the HD660s was known via another source, their purchase was initiated.Personal curiosity about the amp's benefits needed to be satisfied and results for both functions are highly favourable, very evident even for older ears. With both working in consort, low-bass performance is improved, the sound rounder and more characterful helped by a slight rise and smoothness in the high-treble area while the expanded sound-stage is dramatic having eliminated the sense from the HD660s alone that performers who previously appeared to essentially be shoulder-to-shoulder were now spread across a wide area with a well-defined left, right and centre, not each in a single location but with individual isolation. After burn-in, performance should be smoother and more impressive.As a headphone amplifier is almost indispensable, purchasers should undertake their own research to ascertain which best meets their budget and usage requirements as prices range from sub-£100 to low-thousands! Personal choice, initially incidental and with no expectation that the HD660s were soon to be purchased, may have resulted in the perfect partner without breaking the bank!Without doubt, these are the best headphones ever heard although not the first to be of a professional audio standard. There was unsatisfied expectation that there may be an individual performance print-out of the actual unit's audio spectrum, distortion levels etc to demonstrate just how closely the two ear units matched; a similar chart was provided with professional 'phones purchased in the '70s and binned when its gel-filled, non-replaceable ear-cushions solidified over several months one summer.

Overall these are a solid choice if great sound (with some eq), lightweightness, tight fit, balanced connection and strong mids are your thing. They sound great with every genre. They sound nice and loud enough directly without an amp from my Samsung Galaxy S10, but with an amp they really shine. They are very open, which is very nice when using them in a (video)call. Listening to your own voice almost sound natural.That said I also bought recently a pair of Beyerdynamic DT1990pro for basically the same price and apart from the points already mentioned the Beyers are better in every aspect: Better build, better comfort, better accessories (extra pair of ear pads and carry case), better cables. Better sound with more detail, crispier highs and very detailed bass. And yes their biggest problem/flaw is that harsh 8khz spike. So they also need to have some eq.With a strong treble lift on the HD660s both headphone can almost sound identical, but the DT1990pro still has better soundstage, resolution and presence.I let my wife decide which one she wants, but after an initial impression, she also wants the DT1990pro.Just to be clear, the differences are marginally, both headphones are amazing and better than anything we had at hand before like Bose QC15 and QC35II and Beyerdynamics DT 770 pro 80ohm.The QC35II are still my no 1 choice for outdoor and overall comfort, but listening to music on these is hard after experiencing the HD660S or DT1990pro. It's like driving a VW Golf and then Mercedes C-Class ...Update after a month of use: The initial quite strong clamping force is not so much an issue any more and I can almost forget wearing them. I would say they became more comfy than the dt1990pro, especially being lighter and more "airy".BUT: last week I upgraded to the HifiMan Arya Stealth, which are way better than both of them in sound and comfort. Build quality and cable is still better on the dt1990pro. But if you planning to use headphones as your primary sound source the almost 1000 pound price difference is worth it. The sound is drastically better, especially compared to the hd660s and the fact the that earcups are so big and deep that they don't touch the ears at all is amazing. These are truly S-Class ...

Previously I had been a big fan of closed headphones but unless you pay quite a lot more than this Sennheiser 660S, you don't get the same quality sound for a closed headphone. This is strictly in-home audiophile listening. Let me at the outset say which genres of music it does well Techno, Funk, Classical and Jazz are amazing. Rock / Blues/ soul it passes muster. Pairing with a DAC improves the presentation but other headphones could also claim the same. I used it with two British DACS ( Chord Hugo) and IFI Hip DAC. Both the DACS significantly improved the reproduction and allowed the 660s to demonstrate its chops.The sound reproduction is Neutral. Bass is very good, consistent, and the mid-range is well-balanced and clear. Treble is ok and achieves good harmonic balance. Bass could be a bit more but as Sennheiser has pitched this headphone as an audiophile product ( quite a few hundred pounds below their flagship HD820) this does what it says with aplomb. Low levels of distortion, when paired with an appropriate amplifier, are also evident and continues into the high-level ranges. This is where these headphones shine, especially in the low bass range, where almost all competitors at this price point reach their limits more easily.There are no electrical tricks such as noise cancellation or sound processing. There is no Bluetooth and when it comes to Hi-resolution playback it delivers - in spades. Comfort is good, not great as I found it tightly clamped onto my head but was not tiring, though I am unlikely to wear these all day as I would do similar priced Japanese brands.It will show up shortcomings of poor recordings and therefore if you feed it quality stuff you will get quality listening experience. Sennheiser has provided a decent length of cable and connectors and adaptors, including:4.4-mm balanced Pentaconn and 6.35-mm connectivity (3.5-mm adapter supplied)Detachable cable with a 6.35-mm connectorDetachable cable with a balanced Pentaconn connector.In summary, this is a worthy successor to HD 650 and offers much in the way that you could expect from the higher-priced HD820 ( though that is a big step above). This 660S is also a significant step up from the HD 560 which I trialled but rejected as it did not handle Hi res sources all the well. For in-home listening and in-home listening only, this is one of the best in the market.

I had really high expectations for these headphones. Sennheiser 600 series phones have always been held in high regard. Comfort is excellent, yes they clamp fairly hard but i like this although some people may not. The clamp enables a good seal with these headphones. In terms of sound it’s a little mixed. If your going to listen to these with just a mobile device like a phone or tablet I would say it’s a waste of your money. These phones are beyond being pushed to their best with just a mobile device. An external DAC & headphone amp is a must to get the best from them. If you use them with a quality DAC & amp then be prepared to hear everything with excellent clarity & sharpness. If you use them with just a mobileOr tablet they will definitely underwhelm. They sound muffled & underpowered when used this way. So in conclusion I agree the 600 series legendary status remains but only if used with high quality equipment.*****************************************Update****************************************I`ve had these headphone for few weeks now. I stand by my review but should add some extra information.I`ve listened to some older recordings via streaming & the sound is good but not great. Certainly not what I would expect from headphones at this price. Even using an external DAC & headphone amp the sound was acceptable but I wanted more.I connected the balanced lead to my headphone amp & listened to the same recordings. They sounded a bit clearer but still not amazing. I then listened to some newer current music & the sound is incredible. Everything suddenly sounded crystal clear & I could hear everything in the recording. Every instrument or sample was the best i`ve heard them. I could even hear new sounds in songs that I knew well.My advice is that using these headphones with a decent DAC & headphone amp with modern recordings is definitely worth the purchase price. If you want to listen to older recordings even with a good DAC & amp you won`t get the best from these & are wasting your money. Hope this advice is helpful.

Headphones are a strange thing, just like music. What one person loves another would hate. So instead of me being pretentious like so many other Audiophiles seem to be I will just tell you "my personal" good or bad points of them and let you be the judge.My best points.1, The sound quality is like you are in the music (i.e., the soundstage), it makes you feel connected to whatever you are listening too.2, You should not "Need" to use any +- bass or treble, they sound great "Flat". Just how the makers of the sound intended it to be.3, I am discovering music all over again even though I own some "HD 595's", I mean they are 15 years old but they do still sound amazing.My good points.1, They work "ok" plugged straight into my PC. Not great... But good enough for most people I would expect. If you want the best for them then you will need to get a decent amp.2, You get 2 different cables and an adapter so that they will plug straight into your gear even if you have the "In-between" size plug.3, The cables are also changeable.My bad points.1, They are quite tight, but it's also a good thing because then you can "Break them in" to the size of your head.2, Some people would say they lack bass. Which they totally do, but I also have "HD 595's" and "HD 280 pro v2" and the "HD 660 S" sound FAR better. The bass is there and there is a very big improvement over the "HD 595's" but quite similar to the "HD 280 Pro V2", however the "HD 660 S" quality over price increase from the "HD 280 Pro V2" is more then worth it IMO.3, The cable joins to each side of the headphone which is great because of balance, however the cable joins together too close to the headphones for my taste and get caught up sometimes.I might add to this list later, but I hope it was helpful.Have a nice day.

A clear step up from my 20+ year old £150 sennheiser HD565 OVATION headphones but the price is very high. They also lack deep bass which is disappointing for £429! They do other things very well though such as instruments sound more accurate than my old model, snare drums and cymbals sound more realistic too. The lack of low bass can make following complex bass guitar lines impossible.Despite the few flaws, they are generally enjoyable to listen to but a bit tight on my head. Hopefully they'll soften up in time?

I have a pair of Sony WH-1000XM3 wireless noise cancelling headphones which I use in the Gym and while traveling which sound amazing. I Have been looking at getting a pair of open back headphones for home use and pairing with my Astell & Kern SR25 but I didn’t won’t to pay a £1000 or more but read a review about these. I am so pleased I purchased them as I feel the sound quality is better than my Sony’s which have constantly been voted best wireless headphones. These give a more natural sound with good but not overwhelming bass, the sound appears wider than the Sony’s, I now only use the HD 660 S in the house and not my Sony’s.As they are open back you can hear any sounds around you, also they do bleed out a little sound. Having said that I often use them while my wife watches tv and I can enjoy my music and my wife does nor hear it from around six feet away.They are comfortable to wear for long periods and come with two leads and an adapter, just above the ear cup where it joins the headband there are three dots which is Braille for L signifying the left ear cup, some people have said you cannot see which is left or right but just feel the dots and that’s the left one.I highly recommend these headphones, a bit expensive but compared to other HiFi headphones not too bad. I have tested various headphones including the Sennheiser HD 820 which cost £1800 and the difference is minimal.

I've been on a journey and tried and bought a lot of headphones over the last 8 years, mostly by akg, sennheiser, beyer dynamic and bose.I concluded I needed wired and open backed for use at home, as closed backs neither sounded or felt as natural.I've a headphone amp but also like the convenience of being able to power via phone if needed.The 660s do it all and are my go to pair.I like...Sound. Not as exciting as some but undoubtedly the most rounded. They just get everything in balance neither showing off in the bass or thrilling with exaggerated treble.The fit. Not too tight for me. Velour is vastly preferable to leather as it never feels hot or sweaty. Unlike some other phones I've tried my ears don't touch drivers. Clamping not to strong but they don't slip like looser phones including hd599.Cables. I like detachable cables and bought a third party short 3.5mm for phone. Swapping is easy.Ohms. They still seem indefinably better with amp but work just fine powered by phone.Build. Plastic but feel premium and light. Don't look as dated as hd600I wish...They came with a short dedicated 3.5mm cableI dream...One day there will be open backed wireless headphones just like these.

These sennheiser headphones deliver some of the best audio quality i've ever heard. Bass is practically non-existant however so I use an equalizer for that. They're very comfortable.

I'm not an experienced reviewer, and still fairly inexperienced with this tier of headphones. But maybe my experience with these headphones as an average audio enthusiast might help some likeminded individuals decide if these are worth checking out or not.The setup and sources I usePrimary Source/DAC/Amp: Fiio X5 mkiiiMusic sources: Spotify Premium, HiFi, Flac, 320 kbpsBuild qualityNo complaints here. Even though the exterior is mostly plastic, the frame of the headband is made from aluminum, and does not feel cheap or vulnerable at all. The plastic allows these headphones to be very light, which contributes greatly to the comfort. The HD 6-- series have been known to endure for decades when properly taken care of, and I have not found any reason to doubt that.ComfortThis might be the most significant selling point for me. They are definitely not very comfortable right out of the box, since the clamping force is initially quite prominent. Also the pads are fairly stiff, which in combination with the clamping force, puts a fair bit of strain on the arms of my glasses. They still were more comfortable than many headphones I've owned before though.As time progressed, the headband loosened up, and the pads had worn in, forming to the shape of my head. Since then, they haven't been uncomfortable at all anymore, and I've been able to keep them on for endless hours without feeling strained. Like many others have said, you just forget that you're wearing headphones after a while.Power requirementsThey are rated at a nominal impedance of 150 ohms, and are advertised to not require a dedicated amp for good results. While I do agree that these sound absolutely fine with my iphone X and galaxy s9+, but i primarily use a Fiio X5 mkiii player and that has definitely shown a worthwhile improvement. Not only to achieve satisfactory levels of volume, but also to remain free from distortion at much higher volume levels than my on-board audio. It just sounds more effortless and linear overall.SoundBassThe bass on these is tight, quick and punchy. Without EQ, the amount of bass is leaning more towards being bass-light, which isn't optimal for bass-heavy genres like modern hip-hop and various electronic subgenres. There is still a decent amount of mid-upper bass, which is sufficient to nicely complement instrumental/vocal focused genres like rock, jazz, soul, classical etc. With EQ, the bass can be elevated quite a lot without sounding distorted or awfully off. Also, with tracks that have a lot of loud bass going on, the bass does start to audibly struggle quite a bit, and can at times sound a bit distorted. Overall, it's not capable of being a bass-cannon, but for my likings, it's capable enough.MidrangeThis is regarded to be the main reason why the 6-- series has been so popular for over 20 years, and rightfully so. Vocals sound impressively clear and forward, definitely the most realistic representation of vocals I have heard on any headphone. Even realistic to a degree where you can almost feel the breath of the singer. Intrumentals are also presented with magnificent detail and separation. Opposed to the HD 600 and 650, these don't sound veiled at all. Vocals are very much in-your-face, instrumentals right behind it, without feeling like anything overshadows anything. Very impressive!TrebleI am quite treble-sensitive, which contributed greatly to why I like the 660 S more than the 600 or 650. To my ears, the treble is already leaning towards the brighter side, but the EQ conveniently smoothens it out just enough to hit the sweet spot for me. The slightly recessed treble does translate into a mild loss of fine details and sparkle in that area, but for my own listening enjoyment, this tradeoff is worth it for me.SoundstageThe soundstage on the HD 660 S is decent, but not impressive. It's still wider than any closed back headphones I have tried, and there is enough width to get a proper sense of separation and distance. It sounds a bit wider than the 600/650 to my ears, but this might be because there appears to be a bit more air in between different sounds. On the 600/650, adjacent sounds can sound a bit more like they are transitioning into one another, while the 660 S sounds like there is much less of a transition, and more air in between sounds.Final verdictThe HD 660 S does a lot of things exceptionally well, and has not revealed any major flaws. The combination of comfort, the beautifully balanced sound signature that never fatigues, the resolving capabilities, the flexibility to EQ this to a wide variety of different sound signatures all make this a headphone that is very difficult to criticize.

J'avais essayé 3 types différents de casques avant, un très entrée de gamme de marque JvC, un Sony WH-H900N ainsi qu'un AKG K371.Le sony était bien mais trop étouffé et trop dans les basses, le son était cependant vraiment présent, les termes anglais seraient plutôt lush/full.Pour le AKG K371 il était plat, froid, métallique, aucun plaisir d'écoute sans mettre des equalizer pour réchauffer tout ça.Le HD 660s n'a pas eu besoin que je fasse tout ça, le son était vraiment incroyable dès le début (Très bonnes basses, son agréable, musical, assez chaud, voix claires et aigüs pas aggressif) : Et détrompez-vous j'ai largement assez de volume sans aucun DAC/Ampli externe, et j'ai encore vraiment beaucoup de marge pour les sources sonore plus faibles.Les personnes qui disent que les casques ouverts n'isolent pas le son, a mon volume normal d'écoute on entends rien a plus de 20cm. Cependant, on entends sans problèmes les sons externes donc c'est fait pour une écoute dans un environnement calme. Aucune chance de déranger quelqu'un qui est dans une autre pièce, par contre.Le seul défaut que les puristes pourraient trouver seraient une légère absence de suraigus ? Mais ça ne me dérange pas, le son est vraiment très harmonisé et on entends vraiment tout. Sachant que j'ai les oreilles sensibles, je n'ai eu aucun problèmes.L'essayer c'est l'adopter réellement.

Después de dudar entre los HD 650 y estos HD 660S, me he decidido por los 660S y creo que ha sido un acierto.La impedancia de los 660S es 150 ohm, la mitad de lo normal en esta gama HD (300 ohm), lo que significa que los puedo utilizar en mi móvil LG V30. La música Moderna -grabada a un volumen alto- se escucha con margen en un reproductor normal tipo Rocket, y para la Clásica he necesitado el reproductor Neutron que cuenta preamplificación de auriculares, con la cual queda margen de volumen.He de decir que la primera impresión con los 660S no es impresionante, el sonido resulta natural con unos garves excelentes, pero la mejor prueba de la maravilla que son es que tras un rato de uso, al intentar comparar volviendo a mis auriculares Bang&Olufsen de oreja (150 €) y unos Sennheiser abiertos de la Gama 400 del año 95, que ambos me parecían lo que son, más que decentes, ahora me paracen unas auténticas carracas planas sin la menor profundidad...Al final el resultado de los 660S con un buen móvil de audio como la serie V de LG que cuenta con DAC Hi-Fi de 32 bit hasta 384 KHz, es espectacular...Comentar que como complementos veo casi necesarios tanto un cable corto (1,5 m) como una funda de protección. El cable que trae es de 3 metros y muy 'pesado', nada operativo para usar con el móvil o un amplificador en la mesa del escritorio, enseguida acaba colgando hasta el suelo con el peligro que conlleva de pisarlo y aplastarlo con la silla. Asimismo la caja que trae es enorme si se desea utilizar como protección entre usos.Muy satisfecho.

Wenn ich den HD 660 S mit nur drei Wörtern umschreiben müsste, würde ich sagen: klar, straff, knackig. Und das von den hellsten Spitzen über die Mitten bis hinunter zu den dunkesten Tiefen. Dank neu konstruierter Schallwandler ist den Ingenieuren von Sennheiser wirklich ein großer Wurf gelungen. Die 600er HD- Serie ist ja sowieso schon legendär und hat mit dem 660 S bis jetzt seinen Höhepunkt gefunden. Selbst sein großer Bruder HD 800 S dürfte über die Klangqualitäten des ,,Kleineren'' überrascht sein. Beide Hörer liegen klanglich nicht allzu weit auseinander, mit zwei Unterschieden. Der ,,Große'' ist viermal so teuer und macht nicht so viel Spaß wie sein kleinerer Bruder der 660 S. Allerdings kann die große Bühne die der HD 800 S vermittelt nicht erreicht werden. Eine analytisch - neutrale Klangwiedergabe ist ja gut und schön, kann aber auf die Dauer auch etwas steril bis langweilig wirken. Das ist natürlich alles subjektiv zu sehen, ist eben wie vieles im Leben Ansichtssache.Besonders anschaulich wird die Klangfreude beim Hören mit dem 660 S Techno Pop Musik, Kalkbrenner, Yello, Kraftwerk, Tomorrowland usw. , aber auch Beethoven`s ,,Neunte Sinfonie'' oder Tchaikowski's ,,1812'' sind ein großes Erlebnis. Luftig und Klar, straff und knackig sind die Besonderheiten des Klanges vom HD 660 S. Natürlich kommen auch die sanften, zarten Töne geschmeidig herüber. Der beinwippende Zuhörer wird förmlich in die Musik hinein gezogen, ist ein Teil von ihr. Mehr kann man eigentlich nicht verlangen und das zu einem Preis der gut und gerne doppelt so hoch sein könnte. Und selbst dann dürfte man immer noch das Gefühl haben den HD 660 S günstig geschossen zu haben. Aber das wollen wir mal gar nicht allzu laut sagen und behalten es für uns.Die Kabel sind auswechselbar und der Tragekomfort besitzt einen angenehm festen Anpressdruck. Stundenlanges Hören ist kein Problem, zumal 260 Gramm kein großes Gewicht darstellen. Der 660 S zählt zu den leichtesten Hörern seiner Art. Einzig negativ sind die Außengeräusche die bei ruhigen Passagen durchdringen und auch die Tonabstrahlung nach Außen hin ist recht eindeutig. Aber das ist halt dem offenen System geschuldet. Verarbeitung und Design sind sehr gut und solide, eben auf einem angemessenem Niveau. Auch große Ohren finden bauformbedingt ihren Platz ohne gequetscht zu werden. Mit einer Nennimpedanz von 150 Ohm klingt der HD 660 S auch an meinem i Pod ausgezeichnet.Solange die Preisgestalter von Sennheiser es mit uns audiophilen ,,Spinnern'' so gut meinen, gibt es eigentlich nur eins: bestellen, sich auf die Lieferung freuen und dann einfach nur genießen und Spaß haben.Dafür volle Punktzahl und Ende der Durchsage.