Customer Ratings & Reviews

I used to be a die-hard HD650 fan before buying these headphones. I found the HD660S to be a great improvement and overall upgrade. The bass is tighter and more controlled. The mids are very cohesive and detailed. The highs are definitely more present, which should be considered if you are treble sensitive. I don't find them to be harsh or sibilant at all. The sound stage is noticeably wider and the imaging is more precise than my older HD650. The HD660S is also far less demanding in terms of amping. They sound great on every headphone jack I've tried them on so far, but the truly shine with a dedicated DAC & amp. I can listen to these for hours with music and games without discomfort or fatigue thanks to the thicker/deeper earpads compared to the HD650. I highly recommend these headphones to anyone who wants to see what the Sennheiser HD600 family of headphones are capable of.

Bass could be a little more punchy but very good for an open back design. Very nice sound stage. Very airy and open. Highs are crystal clear. Some reviews say it fits too tight. I don't see this. I think the clamping pressure is just right. They are great for audiophile listening and instrument mixing as well. Very nice overall design and construction.

Coming from the 560 I love them. Excellent but need an amp for sure …. Just my opinion anyway….. but ya it needs juice to run well

Super clear audio, not fatiguing, surprisingly comfortable. They are a little tight on the head at first, but they loosen up quickly. Fantastic for long listening sessions. My only complaint is the bass is a little lacking. There is a pretty significant rolloff around 100hz. Other than that, these are awesome.

These headphones have excellent sound quality but I am unable to wear them for extended periods of time because the top part of the headphones squeeze on my head which gives me a headache after a while. I dailied these for a while to see if it could be broken in but the issue still remains. I have gone back to my Sony mdr-1am2's for daily use because they're much more comfortable and still have solid sound otherwise. Your mileage may vary

I have owned Sennheiser headphones in the past, great open airy sound, lots of detail, I have about 30 hours on these cans and they are really starting to open up. Very comfortable, a little tight at first but after about 3 days of use they fit just right.

Excellent, although I vastly prefer Sennheiser HD 600 when comparing these side by side. Out of all the headphones I've tried so far (under 600$) I'd rank my all-time favorite as: 3. Sennheiser HD 560 - 1.25/3 of HD 600. 2. Sennheiser HD 660S - 2/3 of HD 600. 1. The HD 600 - nearly perfect. There is a bit of a warm veil which makes listening to HD 660S more comfortable for longer sessions, however listening to them after 600 I constantly felt like something is missing and the music wasn't as satisfying as it was. Mids aren't as great as HD 600. Presentation and the box are surprisingly better than HD 600. If you know what warm neutral is and if you want sound that's not as exciting and satisfying as 600, 660S is a great choice. It's still miles better than most headphones, just not as good when you're familiar with 600. 560S is a good alternative to both of these if you really can't justify going over 300$ but I'd still encourage to try 600, they're worth it.

These are the first pair of REALLY good headphones I've had. Detailed and clear with precise bass that isn't overpowering. The open ear design makes the music feel more spacious, like it's coming from all around you. Please note, to really get the 660S to sound its best, you must have some type of amplification. Plugging into a receiver is a good starting place, but you'll probably want to purchase a headphone amplifier. The 660S will take as much power as you can throw at it.

These sound great. I ended up spending the extra money to get the HD 800s and I love them.

Build quality is above averge. Sound excellent for price.

This headphone takes the drivers from the HD700 and tweaked them a bit. Overall I felt like it took the best of the sound qualities from the HD600 / 650 & combined those qualities into one endgame headphone for those who like the 6XX line. This headphone has all the smoothness and warmth of the 6XX line, while adding a little bit more detail and clarity to the highs / treble. Female vocals ( HD 600s trademark ) manage to sound even more angelic and special on this HD660. The bass is more or less the same as the HD600 but has just slightly more impact and thump. Not as much as the HD650 and not for bass heads either. If you like bass the HD650 is still the one for you and still has the warmest sound signature.

Probably the best headset I've ever owned. Works extremely well for listening to music, watching media or even playing some games. Its super comfortable and very well built, can be use for hours at a time without much discomfort.

The HD 660 S is a top quality sounding perfect headphone.Great for use portable field recorders and Hirez audio players.The HD600 and the HD 650 is the better value.The Bass is slight tuned little low, the mids and the hights are perfect.The impedance is 150 Ohm,so this is easier for your hi-Rez player.Recomended!

These headphones are great! I went from my Hifiman Sundara's to these and was greatly surprised. The soundstage isn't as wide and its not as crystal clear or detailed as the sundara's but super comfy and they are still very wide soundstage feeling. The build quality imo may not be worth roughly $400+ but in terms of qc issues (which is what I've heard is a big issue from others with other hifiman headphones) it is much more refined and sleek looking. I definitely recommend these and I recommend an amp for these because it is 150 ohms. Ive heard getting a tube amp will make these as well as other sennheiser headphones shine better but I can't say from experience.

Used it with my Schiit Valhalla 2 and the differences between the Sennheiser HD6XX (HD650) and this is minimal. If you own the previous Sennheiser HD600 models and if you don’t have a finely tuned ear or listen to music while doing something else you will not hear the difference between this and the other models. But as you know with most things, sound is very subjective! One plus is that you do get a balanced cable!

These headphones completely changed the way I looked at audio only down side is a 500 dollar problem price tag but they are worth it

Quick delivery excellent packaging everything was in perfect condition. The fit, style and sound is incredible. Just awesome!!!!!!

The HD660s is phenomenal! One of the best audiophile headphones especially is the sub $500 catagory. It is a complete step up from the HD 600 & 650.

Awesome with the right Dac and AMP combo. Bought for gaming and music. For gaming the positioning is the best and the explosions are insane. For music the Bass is super rich and just good quality on the other frequencies

Love this headset I mean love them if you don’t plan on buying a amp for them them don’t waste you’re money on them buy something cheaper but if you pair it with any amp there wonderful