Sennheiser HD660S Review (Headphone)

[Jimmy]

I love my 20+ year old HD600 and for between 300-400€ I would consider buying an improved refresh, but at almost 600€, the S2 it's not for me, maybe if my unit fails, the regular HD660 may do.

Also, Fiio has just released a new headphone that FR wise, seems to be close to the Sennheiser HD6?? family, but with increased bass, anyway it's very new so I'll wait for more reviews, these are some measurements from Kuulokenurkka, compared to HD650 and HD600 (I haven't been able to add the HD660) :

Squiglink - Headphone frequency response database by Kuulokenurkka

Compare hundreds of frequency response graphs between headphones from manufacturers like Beyerdynamic, Hifiman, Sennheiser, and more.

kuulokenurkka.squig.link

Large Dynamic High-Res Over-Ear Headphones FT3

FT3Sound comes from the vibration of material – thus, the choice of the driver is quite important in determining sound quality. The FT3 features a large 60mm dynamic driver, uncommon in its class. Compared to a smaller driver, the FT3 can push more air and convert energy into the sound more...

www.fiio.com

(edit): I correct myself, there's an important difference at aprox. 10Khz, at the same website there's an extra measurement with felt that tames that peak, so at stock these seem to have hotter treble than the Sennheisers.

 

[ugur38]

@Jimmy TechPowerUp reviewed new Fiio FT3 but it's in early access for Patreon supporters. VSG (reviewer) also measured it and you don't need to be supporter to look at it:

Squiglink - IEM frequency response database by VSG

Compare hundreds of frequency response graphs between IEMs and earphones from manufacturers like Moondrop, Sony, 64 Audio, Fiio, and more.

vsg.squig.link

 

[Zensō]

My HD 660S2 review is up.

Thanks so much for the extremely thorough and thoughtful review!

 

[Jimmy]

Thanks, however FR measurements don't tell the full picture, and that's why more in depth technical reviews from people like Solderdude and Amir are very interesting, I've been bitten more than once purchasing equipment based on early impressions, for example, when released the Fidelio X2 were touted by many as improved HD600s, but while being good, at least for me they were quite different, and I much prefer the HD600.

What I believe something like the Fiio FT3 shows, at least based on the accesories and materials used, is how overpriced many upper tier headphones seem to be nowadays, specially compared to speakers.

My HD600 are still going strong, but now that the HD660S2 have arrived, if a good deal for the HD660S appears, I may give them a try.

@Jimmy TechPowerUp reviewed new Fiio FT3 but it's in early access for Patreon supporters. VSG (reviewer) also measured it and you don't need to be supporter to look at it:

https://vsg.squig.link/?share=Harman_2018_Over-Ear_Target,FiiO_FT3_suede[/U

 

[Robbo99999]

Thanks, however FR measurements don't tell the full picture, and that's why more in depth technical reviews from people like Solderdude and Amir are very interesting, I've been bitten more than once purchasing equipment based on early impressions, for example, when released the Fidelio X2 were touted by many as improved HD600s, but while being good, at least for me they were quite different, and I much prefer the HD600.

What I believe something like the Fiio FT3 shows, at least based on the accesories and materials used, is how overpriced many upper tier headphones seem to be nowadays, specially compared to speakers.

My HD600 are still going strong, but now that the HD660S2 have arrived, if a good deal for the HD660S appears, I may give them a try.

Upper tier headphones in terms of price are very often well over priced for what they deliver, there's not massive amounts of correlation between price and sound quality as proven by some Harman research done years ago, and that still is true today. With headphones you have to research the measurements and then try them out. Speakers probably correlate a little more with price vs sound quality, but again it's a loose correlation....and again you'd want to be making sure it's been measured properly here on ASR or another site that follows similar practices. Just don't think about the price when assessing the quality of a headphone, instead just at the point if you decide it's worth buying, price is not sound quality.

 

[Urushi]

The HD660s is $275 on Amazon. I loved my HD6XXs. I like techno and electronic music and the HD6XX didn't feel the most responsive for that but I still liked them anyway. I am wondering if I should buy the HD6XX again for $190 or buy the HD660S for the $275? @solderdude does mention them as being an upgrade over the HD650.

The only other headphones in the HD series I have heard are the HD800s which were amazing.

 

[MiloTheFirst]

The HD660s is $275 on Amazon. I loved my HD6XXs. I like techno and electronic music and the HD6XX didn't feel the most responsive for that but I still liked them anyway. I am wondering if I should buy the HD6XX again for $190 or buy the HD660S for the $275? @solderdude does mention them as being an upgrade over the HD650.

The only other headphones in the HD series I have heard are the HD800s which were amazing.

in my subjective opinion the hd650 feel too bloated in the mid bass. the 660s feels less cluttered with the down side that it is lacking a lot of treble at stock tunning, if you are very confident about your EQ skills the 660s will sound better, but if your main interest is electronic music I would suggest checking out the 560s over the hd600 series, at stock tuning the 560s already have better sub bass extension and then they are also very receptive to EQ. they just have a slight resolution penalty compared to the 600 series but in my opinion thir tuning is just a delight for soundtracks and electronic music. they often go for 140€, at that same price you could also look at the good ol DT770 80hm version, they are surprisingly airy for a close back and zi find the level of bass very fun for EDM and trance. they can be sibilant for voices sometimes but for anything that is just instrumental there is no problem.

 

[Shiva]

I’m still using and digging my original Sennheiser HD580’s. Any reason to upgrade from them to a newer model.

 

[Urushi]

in my subjective opinion the hd650 feel too bloated in the mid bass. the 660s feels less cluttered with the down side that it is lacking a lot of treble at stock tunning, if you are very confident about your EQ skills the 660s will sound better, but if your main interest is electronic music I would suggest checking out the 560s over the hd600 series, at stock tuning the 560s already have better sub bass extension and then they are also very receptive to EQ. they just have a slight resolution penalty compared to the 600 series but in my opinion thir tuning is just a delight for soundtracks and electronic music. they often go for 140€, at that same price you could also look at the good ol DT770 80hm version, they are surprisingly airy for a close back and zi find the level of bass very fun for EDM and trance. they can be sibilant for voices sometimes but for anything that is just instrumental there is no problem.

I was very happy with the comfort of the HD6XX is the 560s similar?

I have tried a DT990 Pro 250 ohm and I really disliked the sound.

 

[Urushi]

I am kind of torn between the HD58X Jubilee, the HD6XX, and the HD660S. The HD660S is only $100 more...doesn't seem to be that well liked but I do want something different.
Would any of these be good for studio mixing and video editing?

 

[D00M]

I am kind of torn between the HD58X Jubilee, the HD6XX, and the HD660S. The HD660S is only $100 more...doesn't seem to be that well liked but I do want something different.
Would any of these be good for studio mixing and video editing?

All depends on your preference. You kind of have to listen to them in person. Unless you have so much experience that you can infer the sound signature from graphs and written review.

I own HD660S and HD560S. I heard HD600 in the store. I have not heard HD6XX.

I really like HD660S. Although HD560S has more bass extension (that it goes deeper), HD660S upper-bass level is higher. I listen to pop and alternative. I hear more bass from HD660S. In addition, HD660S is more dynamic and has more bass impact/punch/slam.

In terms of soundstage, HD660S is also quite surprising. HD560S has larger soundstage than HD660S. All the HD6** series have intimate soundstage. However, HD660S has very good separation and layering, comparable or better than Hifiman planar magnetic like Sundara. Instruments are distinct and provides this 3-dimensional soundstage. Very realistic.

 

[Robbo99999]

I was very happy with the comfort of the HD6XX is the 560s similar?

I have tried a DT990 Pro 250 ohm and I really disliked the sound.

HD560s has more space for your ears than the HD600/650/6XX, so from that point of view it's more comfortable. HD560s has maybe a slightly higher clamping force, but I find them totally fine from that perspective.

 

[solderdude]

Would any of these be good for studio mixing and video editing?

Only with EQ, otherwise you might end up with a too forward/bright sound.

 

[Urushi]

Only with EQ, otherwise you might end up with a too forward/bright sound.

What would you recommend without EQ other than the HD600?

 

[solderdude]

HD600 needs EQ for music enjoyment.
I can listen to the HD660S2 for a long time but at some points I am wishing for a bit more bass extension and a bit more clarity.
A bit in between HD600 and HD660S2 ... with subbass extension
A headphone that comes really close to this ideal (but is less comfy) is the OLLO S5X (with felt disc).
Treble quality is better on HD660S2 (which does differ a bit from the HD660S) compared to the S5X but tonality is better on S5X... there is always something to want.
Also HD560S with a filter is good enough for me as is DT1990 with a filter and A-pads but again these 2 just don't cut all the mustard.

 

[D00M]

I was very happy with the comfort of the HD6XX is the 560s similar?

Comfort and fit are quite personal. I prefer HD6** on both earpads and clamp.

HD6** series have slightly smaller earpads (just a tad smaller), but thicker padding. So if you have big ears top to bottom, then HD6** might touch top and bottom, but less chance of touching the driver.

HD560S has slightly larger earpads but shallower. And it has angled drivers with a block at the rear of the driver that sticks out. Here is a photo and you can see that trapezoidal block: https://www.headphonecheck.com/wp-c..._September22760-501912-scaled-1-1920x1080.jpg

It might not seen like much, but that is near the ears. Some people complain that their ears touch this. If you have large ears that stick out, and if you don't like touching to the widest part of ears, HD560S might be a problem.

I don't have big ears. For me, I don't mind if my earlobes (bottom) touch the earpads, which is soft. I hate it when the widest part of my ears touch driver, which is not soft and can have various textures.

For clamping force, HD660S is higher than HD560S. Which I'm prefer. HD560S loosened up too quick and too much.

 

[aliaksej]

Ordered Sennh S560s which seems making sound thinner then it is. At least tenor voices, piano. While overall very pleasant and conmfortable headphones. Enjoyed a lot listening to power/sympho metal on low volume.
Also testing DT 900 pro x which have more linear FQ but are heavy, hotter for ears and much more solid mids. Also feels more closed then 560s. I'd add some more treble.

Will s660s have more body in mids so sound will be comparable to monitors and beyers 900?

Currently 660s are on sale for 320 usd which is the same as for s650/600.

 

[Robbo99999]

Ordered Sennh S560s which seems making sound thinner then it is. At least tenor voices, piano. While overall very pleasant and conmfortable headphones. Enjoyed a lot listening to power/sympho metal on low volume.
Also testing DT 990 which have more linear FQ but are heavy, hotter for ears and much more solid mids. Also feels more closed then 560s. I'd add some more treble.

Will s660s have more body in mids so sound will be comparable to monitors and beyers 900?

Currently 660s are on sale for 320 usd which is the same as for s650/600.

DT990 is not a more neutral headphone than the HD560s, as seen by the measurements of the two headphones the DT990 is far from linear:
DT990:

Beyerdynamic DT990 (fresh earpads).pdf

Shared with Dropbox

www.dropbox.com

HD560s:

Sennheiser HD560S.pdf

Shared with Dropbox

www.dropbox.com

The HD660s should generally be a more inferior headphone than the HD560s judging by the measurements
HD660s:

Sennheiser HD660S.pdf

Shared with Dropbox

www.dropbox.com

I would never advise someone to buy the HD660s when there are better & cheaper headphones available. I think you should use some EQ on your HD560s like we talked about in that other thread, or you can try solderdude's physical filters that he inserts into the headphone cable, but parametric EQ is gonna be more flexible and ultimately better if you can find a way to do that.

 

[Limopard]

Ordered Sennh S560s which seems making sound thinner then it is. At least tenor voices, piano. While overall very pleasant and conmfortable headphones. Enjoyed a lot listening to power/sympho metal on low volume.
Also testing DT 990 which have more linear FQ but are heavy, hotter for ears and much more solid mids. Also feels more closed then 560s. I'd add some more treble.

Will s660s have more body in mids so sound will be comparable to monitors and beyers 900?

Currently 660s are on sale for 320 usd which is the same as for s650/600.

The 660s very likely isn't the right headphone for you. It's darker than the 560s due to the missing treble spike @7k. Bass quantity is quite similar, bass extension is a little less deep. If you want to add more treble to the already v-shaped frequency response of the DT 990 you won't be satisfied with any of the HD 600/650/660 series. A full-bodied sounding headphone for low volume listening and good comfort is not that easy to find - maybe Philips Fidelio X2 is worth trying.

 

[aliaksej]

The 660s very likely isn't the right headphone for you. It's darker than the 560s due to the missing treble spike @7k. Bass quantity is quite similar, bass extension is a little less deep. If you want to add more treble to the already v-shaped frequency response of the DT 990 you won't be satisfied with any of the HD 600/650/660 series. A full-bodied sounding headphone for low volume listening and good comfort is not that easy to find - maybe Philips Fidelio X2 is worth trying.

I'm talking about D 900 pro x, not about DT 990 pro. A typo in my message.
I've tested DT-990-250 previously and couldn't take it's treble. Was hurting my ears ))