[kman1211]

If it is possible for you just keep both. For me it is only that, if a headphone does not get enough headtime anymore I let go.

That's the plan, they offer a different listening experience, both are very smooth sounding so fatigue isn't an issue. I'm the same, I'm really just focusing on the Senns currently to break them in and see how I feel about them. I can definitely see myself listening to both a lot

 

[kman1211]

Not too sure what to make of this comparison....
http://majorhifi.com/sennheiser-hd-660s-vs-sennheiser-hd-700-comparison-review/

"Sound
Sennheiser HD 660s
The Sennheiser HD 660s is not a reference headphone. It emphasizes various frequency ranges in the spectrum. ................
The boost at 12kHz is overpowering and doesn’t leave much room for the high, airy frequencies to extend the overall image’s tallness." ..???????

Glad I cannot hear anything above 11khz....lol....but I feel like I'm on a crusade as I'm seeing this too often....could someone please point me in the direction of a recording that has excessive anything at 12kHz, even 8khz. There may be some vastly diminished harmonics happening up there, even harmonic overtones from sustained cymbal crashes should be negligible.... around 7khz I can understand but.....???

And it doesn't stop there...ok I'm still waiting on my 660s but spent over 2 years with the 700s and much more with the HD600 and then the 650s.....maybe the reviewer got confused with which is which......

"Sennheiser HD 700
...........................
While the frequency spectrum feels more natural overall, the soundstage is not as accurate as the HD 660s. It does not have as much width or depth, but it does improve the height greatly!"
........
Similarities
Just by looking at the Sennheiser HD 660s and the Sennheiser HD 700, it is easy to see a few similarities right away."

Hmmmm OK?

Interesting, I'll test with equalizing the 12khz region to see if there is any affect on the soundstaging.

 

[Rob80b]

I've read this "review" some days ago. He seems almost as he has inverted the Hd660s and hd700 names. Crazy.

Exactly what I was implying, for the uninitiated they would end up being led down the garden path. : (

 

[kman1211]

Exactly what I was implying, for the uninitiated they would end up being led down the garden path. : (

Not sure if I agree or not on the review, it is a bit different. Does offer a different perspective, so has me curious if what he says has any stock.

 

[amartignano]

Not sure if I agree or not on the review, it is a bit different. Does offer a different perspective, so has me curious if what he says has any stock.

He says almost exactly the opposite everyone else says and ears (me included) about hd660s vs hd700. Seems as he exchanged the names!

 

[paldepind]

Thank you, really enjoying the headphones, not sure if I'll like them more than my Amiron's or not, that will take time to figure out, but I am actually finding the two to be very nice compliments. The HD 660S do make me realize how much I missed the strong mids of the HD 6xx family.

I'd be very interested in hearing more about how you fell the 660S compares to and differs from the Amiron Home. In particular with regards to low volume listening, bass and soundstage.

 

[Windsor]

I'm loving the HD 660 S. With headphones, to my ears so many of the best available flagship models have many major strengths but also some major sonic presentation flaws, the perception of which can contaminate the experience of enjoying hearing music, and whilst not deemed as a flagship headphone, to me the HD 660 S plays music spectacularly well.

Upon first listen to a burned-in display model of the HD 660 S at Audio Sanctuary UK, I knew this was a great headphone and bought one a few minutes later. As it’s making sense to me now, the HD 660 S - Sennheiser’s successor to the legendary HD 650 - takes the best of the HD 6xx series and makes it way better. Without going into too much detail here, the HD 660 S is like an HD 650 with tighter bass, an even more tonally-balanced HD 600 with much fuller bass, and a headphone facilitating much more musical pleasure than the extremely micro detail-revealing dynamic champion that is the HD 800 whose treble emphasis is certainly not to all tastes. I’m so in love with this headphone and how recorded music is sounding with it right now even as I type this and muchly recommend checking out the HD 660 S if it appeals to you!

As a comparative note, the first time I heard the HD 660 S was also the first time I heard the Focal Utopia which was also on display at Audio Sanctuary, and without a doubt the Utopia will be the next headphone I buy, it being superior to every other headphone I have yet heard - though I haven't heard the new Orpheus yet - in every way, and that being the case when I A/B'd the Utopia with the HD 660 S I intuited that the Utopia is obviously a better headphone, but the HD 660 S is such an improvement on so much relative to the previous HD 6xx and H8xx series that it felt like a such an obvious upgrade to me. The HD 660 S is so deservedly worth of all the success and praise it attracts. I'm so savouring the HD 660 S. Thanks Sennheiser!!

 

[kman1211]

He says almost exactly the opposite everyone else says and ears (me included) about hd660s vs hd700. Seems as he exchanged the names!

Makes me wonder if the reviewer broke them in any. The HD 660 S is a little strained and hard sounding out of the box to my ears, but smoothened up a lot over the weekend, definitely coming across more HD 650ish now.

I'd be very interested in hearing more about how you fell the 660S compares to and differs from the Amiron Home. In particular with regards to low volume listening, bass and soundstage.

I need to spend more time, but in terms of soundstaging and imaging I find the Amiron is the better one here. Bass wise, the bass seems to have a bit more heft on the HD 660 S while on the Amiron it's bigger and more expansive sounding, bass is excellent on both and extends nicely on both. Low level listening, haven't concluded on that, but I find both do quite well at it, the Amiron does extend a bit more up top so will offer a more vivid presentation, the Senns seem to offer a smoother presentation with more forward mids. Haven't listened to the Amiron a lot compared to the HD 660 S yet as I just got the HD 660 S on Friday. Both headphones are very smooth sounding headphones. The Amiron is probably the smoothest Beyer out there and the HD 660S seems to be just as smooth as the HD 650 with better dynamics. Honestly I already like the HD 660 S more than I ever liked the HD 600 and HD 650.

I will offer a proper comparison of the two later on once I fully settle in with the HD 660 S. Maybe in the style of my DT 1990 vs Amiron Home review.

 

[paldepind]

Thank you for sharing your impressions.

I will offer a proper comparison of the two later on once I fully settle in with the HD 660 S. Maybe in the style of my DT 1990 vs Amiron Home review.

I'll be looking forward to that Something in the style of your DT 1990 comparison would be pretty awesome.

 

[Hifivoice]

Being curious about the perceived differences between the Sennheiser HD650 and H660 headphones, I wanted to see if measurement would support my observations. I measured the headphones in the following setups:

• One (*) with the headphone on my head, with the microphone underneath the pads, just above my ear inlet
• Two with the headphones held in the air, with
  • A near-field measurement of the drivers
  • A 1cm distance measurement

The equipment used:

• Source: iMac, 48kHz, 16 bit audio
• Amplifier: iFi Micro iDSD
• Software: Fuzzmeasure
• Microphone: Behringer ECM8000 with M-audio MobilePre mic-XLR to USB (*)

** Headphone measurement on my head **
The measurements on my head show the following response (HD660 = red, HD650 = yellow). Some observations:

• At the mid frequencies the HD660 is about 5dB more efficient
• The shape of the curve is roughly the same

After aligning the curves at 100Hz and at the “somewhat average” treble region, the response measurements compare relatively as follows


Observations:

• The HD660 and HD650 do have some deviations in the treble characteristics up to 12kHz, but up to 12kHz they are mostly the same
• The HD660 has about 2dB more energy in the 200-2.000Hz region (this is where most of the energy of most instruments is situated)
• The HD650 has about 5dB more energy in the low frequencies (this is probably related to the fact that the HD650 is tuned as if it reflects a neutral speaker that is compensated for baffle step in a room.

For me it partially explains the following differences in sound characteristics;

• The HD660 sounds more “energetic”, the HD650 a bit more bass-heavy and “muffled” (in comparison, I still think it is more accurate than tons of other headphones on the market). The HD650 has a bit of a bathtub frequency response when you compare it to the HD660 response. If you listen for a long time to the HD660, and then the HD650 this is exactly one of the observations. The other way around, the HD660 sounds relatively(!!) “canny/nasal” compared to the HD650.
• The difference in audible treble characteristics is more difficult to judge from the above measurements, as the wave lengths are dominated by the (whatever chosen) measurement method, where the reflections are becoming dominant.

** Headphone measurement open air near field **
Measuring very closely to the headphone drivers in the open air, gives the following measurement results for both (HD660 = red, HD650 = yellow). All the peaks and dips are peaks displaced when you measure at for instance 1cm distance. This implies that those peaks and dips are due to reflections of the cups/pads/inner construction, and are not related to some driver issues.



For that reason, I average out the dips and peaks by applying an 1/3rd octave smoothing (considered what we hear mostly anyway, unless very high Q resonant factors would be present, which is not the case). That gives the following figure:


This might hint at a more solid high-frequency response for the HD660. The dips in the 5-8kHz region is probably related to the inner dimensions of the pads (lamba = 6,5cm -> 5.250Hz; lambda = 4,3cm -> 7.950Hz), which is common for both headphones. This leaves for the HD650 (compared to the HD660) peak at 2.5kHz, a dip at 10kHz, and a peak at 16kHz. My suspicion is that the HD650 mimics the diffuse field response as described by Theile (Theile, On the Standardization of the Frequency Response of High-Quality Studio Headphones, J. of the AES, vol. 34, no. 12, December 1986, 956-969), which is not done for the HD660.


Coming back to the audible differences, the treble on the HD660 appears more coherent to me; the HD650 has a high-frequency zizz that is less apparent on the HD660, and lacks energy in the presence area (2-4kHz) compared to the HD650. So the measurements are indicative in that direction, but I would need to do a lot more measurements, blind tests etc. to make it a hard scientific statement (which was not the goal of my exercise).

Anyway, the data is there, and I invite anyone that has other observations based on these curves (besides “measurements make no sense” remarks; I know those type of opinions exist, but it doesn’t bring any news).



** Addendum: Headphone waterfall curves **
Based on the near-field open-air measurements of the drivers, I’ve also constructed waterfall graphs (aligned with the same depth in dB @ 1kHz — forget below 100Hz and above 10kHz due to the measurement duration and the fft window applied). There is nothing spectacular to be seen in terms of differences here, so in that essence besides size (more efficiency and different radiation within the chamber created by the headphone-face connection), the drivers do not pose any obvious advantages in terms of resonances due to applied material or so.

HD650 waterfall:


HD660 waterfall:




** Addendum 2, about the measurements **
(*) I double checked position accuracy by moving the microphone to various places under the pads. Besides a slight shift of peaks and dips in the >3 kHz region (which also proves those are caused by refections due to the headphone/face/ear interactions), this type of measurements shows to be pretty stable and accurate. Because the Behringer has a relative large microphone mouth, it is in general not fully reliable for measurements above 8kHz.



** Addendum 3, more measurements **
https://diyaudioheaven.wordpress.com/headphones/measurements/brands-s-se/hd660s/
https://www.innerfidelity.com/images/SennheiserHD660S.pdf

 

[pietcux]

Being curious about the perceived differences between the Sennheiser HD650 and H660 headphones, I wanted to see if measurement would support my observations. I measured the headphones in the following setups:

• One (*) with the headphone on my head, with the microphone underneath the pads, just above my ear inlet
• Two with the headphones held in the air, with
  • A near-field measurement of the drivers
  • A 1cm distance measurement

The equipment used:

• Source: iMac, 48kHz, 16 bit audio
• Amplifier: iFi Micro iDSD
• Software: Fuzzmeasure
• Microphone: Behringer ECM8000 with M-audio MobilePre mic-XLR to USB (*)

** Headphone measurement on my head **
The measurements on my head show the following response (HD660 = red, HD650 = yellow). Some observations:

• At the mid frequencies the HD660 is about 5dB more efficient
• The shape of the curve is roughly the same

After aligning the curves at 100Hz and at the “somewhat average” treble region, the response measurements compare relatively as follows


Observations:

• The HD660 and HD650 do have some deviations in the treble characteristics up to 12kHz, but up to 12kHz they are mostly the same
• The HD660 has about 2dB more energy in the 200-2.000Hz region (this is where most of the energy of most instruments is situated)
• The HD650 has about 5dB more energy in the low frequencies (this is probably related to the fact that the HD650 is tuned as if it reflects a neutral speaker that is compensated for baffle step in a room.

For me it partially explains the following differences in sound characteristics;

• The HD660 sounds more “energetic”, the HD650 a bit more bass-heavy and “muffled” (in comparison, I still think it is more accurate than tons of other headphones on the market). The HD650 has a bit of a bathtub frequency response when you compare it to the HD660 response. If you listen for a long time to the HD660, and then the HD650 this is exactly one of the observations. The other way around, the HD660 sounds relatively(!!) “canny/nasal” compared to the HD650.
• The difference in audible treble characteristics is more difficult to judge from the above measurements, as the wave lengths are dominated by the (whatever chosen) measurement method, where the reflections are becoming dominant.

** Headphone measurement open air near field **
Measuring very closely to the headphone drivers in the open air, gives the following measurement results for both (HD660 = red, HD650 = yellow). All the peaks and dips are peaks displaced when you measure at for instance 1cm distance. This implies that those peaks and dips are due to reflections of the cups/pads/inner construction, and are not related to some driver issues.



For that reason, I average out the dips and peaks by applying an 1/3rd octave smoothing (considered what we hear mostly anyway, unless very high Q resonant factors would be present, which is not the case). That gives the following figure:


This might hint at a more solid high-frequency response for the HD660. The dips in the 5-8kHz region is probably related to the inner dimensions of the pads (lamba = 6,5cm -> 5.250Hz; lambda = 4,3cm -> 7.950Hz), which is common for both headphones. This leaves for the HD650 (compared to the HD660) peak at 2.5kHz, a dip at 10kHz, and a peak at 16kHz. My suspicion is that the HD650 mimics the diffuse field response as described by Theile (Theile, On the Standardization of the Frequency Response of High-Quality Studio Headphones, J. of the AES, vol. 34, no. 12, December 1986, 956-969), which is not done for the HD660.


Coming back to the audible differences, the treble on the HD660 appears more coherent to me; the HD650 has a high-frequency zizz that is less apparent on the HD660, and lacks energy in the presence area (2-4kHz) compared to the HD650. So the measurements are indicative in that direction, but I would need to do a lot more measurements, blind tests etc. to make it a hard scientific statement (which was not the goal of my exercise).

Anyway, the data is there, and I invite anyone that has other observations based on these curves (besides “measurements make no sense” remarks; I know those type of opinions exist, but it doesn’t bring any news).



** Addendum: Headphone waterfall curves **
Based on the near-field open-air measurements of the drivers, I’ve also constructed waterfall graphs (aligned with the same depth in dB @ 1kHz — forget below 100Hz and above 10kHz due to the measurement duration and the fft window applied). There is nothing spectacular to be seen in terms of differences here, so in that essence besides size (more efficiency and different radiation within the chamber created by the headphone-face connection), the drivers do not pose any obvious advantages in terms of resonances due to applied material or so.

HD650 waterfall:


HD660 waterfall:




** Addendum 2, about the measurements **
(*) I double checked position accuracy by moving the microphone to various places under the pads. Besides a slight shift of peaks and dips in the >3 kHz region (which also proves those are caused by refections due to the headphone/face/ear interactions), this type of measurements shows to be pretty stable and accurate. Because the Behringer has a relative large microphone mouth, it is in general not fully reliable for measurements above 8kHz.



** Addendum 3, more measurements **
https://diyaudioheaven.wordpress.com/headphones/measurements/brands-s-se/hd660s/
https://www.innerfidelity.com/images/SennheiserHD660S.pdf

Not to offend you, but do you really think that the way you measure is scientific in any regard? I would not dare to publish such things.

 

[Hifivoice]

Not to offend you, but do you really think that the way you measure is scientific in any regard? I would not dare to publish such things.

No problem to be critical if it evokes a technical discussion, and not a personal discussion (so "daring" is not the issue here).

Why wouldn't these measurements not be good for a comparative/relative measurement? There is not standard agreed method on measuring headphones and agreement on how a target curve should look like (just like with loudspeakers). What findings would another type of measurement deliver, i.e. what exactly would you want to improve, and what could we conclude more? What exactly is wrong on these measurements, even if some are not the "common" ones?

 

[kman1211]

Thank you for sharing your impressions.



I'll be looking forward to that Something in the style of your DT 1990 comparison would be pretty awesome.

No problem. I am going to do a stand-alone review of the HD 660 S first. But I do plan on a comparison review, I feel these two headphones will be often considered as potential choices in the same price range and offering a proper comparison explaining the differences will help people make the best choice for themselves. The Amiron has been my most satisfying headphone I've owned and the only one that has satisfied me in terms of both sound and comfort without me growing bored, fatigued by, or tired of the sound. I'm not worried about the HD 660 S comfort as I always found the HD 6xx series very comfortable, comfort is already satisfied for me.

The Amiron gets my full recommendation, it just takes a bit of time to fully settle into, it's a headphone that seduces you over time, it's not a love at first listen like the DT 1990 was, I gradually grew a little tired of the DT 1990. On the HD 600 and HD 650 I grew a little bored of them over time. The HD 660 S is shaping up very nicely, like the Amiron it doesn't seem to impress immediately, I seem to be slowly liking it more, it will take a couple months to see how I truly feel about it as a long term headphone, but I'll have a very good feel of the headphone before then.

I'm a little slow with my reviews but taking time helps me be sure of my impressions and I listen to headphones for very long stretches of time, often over 4 hours a day, sometimes up to 8 hours during laid-back weekends if I'm doing a heavy gaming session, Netflix marathon, or just heavy music listening or any combination of the three. I'm a heavy user of headphones.

 

[Rob80b]

.....................

Why wouldn't these measurements not be good for a comparative/relative measurement? There is not standard agreed method on measuring headphones and agreement on how a target curve should look like (just like with loudspeakers). What findings would another type of measurement deliver, i.e. what exactly would you want to improve, and what could we conclude more? What exactly is wrong on these measurements, even if some are not the "common" ones?

May want to check this thread....

https://www.head-fi.org/threads/hea...#different_measurement_rigs_different_results


Jude's preliminary readings....
https://www.head-fi.org/threads/sen...sor-for-the-hd650.862308/page-8#post-13786777

 

[zazex]

So, looking at this thread pretty much every day

I did not like the HD650's, and sold them quickly.
After a year or so of getting them out of my system,
I bought the HD600's (with aftermarket cables), which I like a lot.

And now, just now, I went for the HD660's. Having had many Senn
headphones, I'm very interested to hear what they've cooked up this time
at such a reasonable price (relatively speaking, of course).

Right now, as far as I can see, there's nothing remotely close to this thread
on the (English speaking) internet with respect to solid, clear, well-expressed
information about these headphones.