Sennheiser HD660S Review (Headphone)

[aliaksej]

The pads are angled and are thicker at the back than the front. You may need to remove and rotate one of your pads by 180 degrees.

*edit* Actually, i'm not sure that come angled, mine are now after 3 years of use! I have the <2021 pads, so I think the front part of the pads has compressed more than the back. Comparison of older vs newer pads here: https://www.audiosciencereview.com/forum/index.php?threads/new-sennheiser-pads-measured.24845/

Video showing how to remove and replace the ear pads here...

Great thanks for advice! Swapped pads, positioned correctly. Pads are swapping soo easy. My phones became as comfortable as the pair I initially returned to Thomann a month ago )))

Such comfortable phones, such good sound. Initially they seemed too dark, but after equalising treble I understood that I need equaliser really rarely. And can easily live without equalisation at all.

 

[Tallulah]

hello, audioscientists. Bought HD 660s from Thomann. Wonderful headphones. But noticed that pads are differently installed and are of different height from different sides. Is that normal for new headphones?

The pads shouldn't be angled by default. As a user with glasses, this looks like these pads were used by someone with glasses for a month or two and one of them was rotated 180º after being used. Are you sure these weren't "B-Stock" (returned by another buyer)?

By the fact that one is rotated my theory is that someone bought these headphones, changed their old pads by the new ones, and returned the headphones with the old pads. They could do that because Sennheiser pads are not cheap (40€). But it's strange anyways because these don't look very used, probably a couple of months or so. At least that's my theory.

 

[aliaksej]

I think pads shouldn't be angled by default. As a user with glasses, this looks like these pads were used by someone with glasses for a month or two and one of them was rotated 180º after being used. Are you sure these weren't "B-Stock" (returned by another buyer)?

By the fact that one is rotated my theory is that someone bought these headphones, changes their old pads by the new ones, and returned the headphones with the old pads. They could do that because Sennheiser pads are not cheap (40€). But these don't look very used, probably a couple of months or so. At least that's my theory.

The box had so seal. When I opened a box, it was not accurate inside. I didn't care about it, but the fact is. Have written to Thomann. It's interesting what they will respond.

 

[solderdude]

The pads are not supposed to be angled. If they were there would be a slot somewhere so they can only be mounted in one position or at least marked L and R.
The same mounting method has been used ever since the HD580 first saw daylight and the recent HD660S2 still has the exact same pad mounting.

 

[Tallulah]

The box had so seal. When I opened a box, it was not accurate inside. I didn't care about it, but the fact is. Have written to Thomann. It's interesting what they will respond.

If I remember correctly Sennheiser packaging does not have any kind of seal or adhesive that could suggest if the box was opened before. But anyways the pads do look slightly used. You can check an unboxing on YouTube to see if the cable was not stored as it should be. Anyways I guess Thomann will just replace your unit if it was not sold as "B-Stock".

 

[Robbo99999]

hello, audioscientists. Bought HD 660s from Thomann. Wonderful headphones. But noticed that pads are differently installed and are of different height from different sides. Is that normal for new headphones?

One of the pads looks slightly worn - the one on the right in the rear pic. So either you've worn them for a while and they've changed shape or maybe they're B-stock like another poster suggested. And as solderdude says, they're not angled pads on the HD660S.

 

[aliaksej]

One of the pads looks slightly worn - the one on the right in the rear pic. So either you've worn them for a while and they've changed shape or maybe they're B-stock like another poster suggested. And as solderdude says, they're not angled pads on the HD660S.

How can they be worn non-symetrically? It's definitely impossible. When I noticed the problem with pads width, one pad was worn on one side and another one was worn on another side ))) I used headphones for about 5 hours after unpacking. Also there was some dust inside the box and things were placed inaccurately.

 

[Zensō]

How can they be worn non-symetrically? It's definitely impossible. When I noticed the problem with pads width, one pad was worn on one side and another one was worn on another side ))) I used headphones for about 5 hours after unpacking. Also there was some dust inside the box and things were placed inaccurately.

It sounds to me like a return. Perhaps one pad was replaced after the headphones were returned. I’d ask for a replacement.

 

[Robbo99999]

How can they be worn non-symetrically? It's definitely impossible. When I noticed the problem with pads width, one pad was worn on one side and another one was worn on another side ))) I used headphones for about 5 hours after unpacking. Also there was some dust inside the box and things were placed inaccurately.

I don't know, but as acbarn says above me, it's best to do something about it and get a replacement headphone seeing as you bought this new and not used.

 

[isostasy]

How can they be worn non-symetrically? It's definitely impossible. When I noticed the problem with pads width, one pad was worn on one side and another one was worn on another side ))) I used headphones for about 5 hours after unpacking. Also there was some dust inside the box and things were placed inaccurately.

They don't necessarily compress symmetrically. My right pad has sort of spilled out the back whilst the left is compressed more inwards.

From your pics and description I agree with the others... some use and maybe some swapping seems to have gone on.

 

[threni]

Here are some thoughts about the EQ.

Notes about the EQ design:

• The average L/R is used to calculate the score.
• The resolution is 12 points per octave interpolated from the raw data (provided by @amirm)
• A Genetic Algorithm is used to optimize the EQ.
• The EQ Score is designed to MAXIMIZE the Score WHILE fitting the Harman target curve (and other constrains) with a fixed complexity.
  This will avoid weird results if one only optimizes for the Score.
  It will probably flatten the Error regression doing so, the tonal balance should be therefore more neutral.
• The EQs are starting point and may require tuning (certainly at LF and maybe at HF).
• The range around and above 10kHz is usually not EQed unless smooth enough to do so.
• I am using PEQ (PK) as from my experience the definition is more consistent across different DSP/platform implementations than shelves.
• With some HP/amp combo, the boosts and preamp gain (loss of Dynamic range) need to be carefully considered to avoid issues with, amongst other things, too low a Max SPL or damaging your device. You have beed warned.
• Not all units of the same product are made equal. The EQ is based on the measurements of a single unit. YMMV with regards to the very unit you are trying this EQ on.
• I sometimes use variations of the Harman curve for some reasons. See rational here: https://www.audiosciencereview.com/...pro-review-headphone.28244/page-5#post-989169 NOTE: the score then calculated is not comparable to the scores derived from the default Harman target curve if not otherwise noted.

Good L/R match.

I have generated one EQ, the APO config file is attached.

Score no EQ: 44.0
Score Amirm: 49.7
Score with EQ: 97.8

SENNHEISER HD 660 S Score EQ Flat@HF 96000Hz
June082022-155600

Preamp: -10.9 dB

Filter 1: ON PK Fc 21.74 Hz Gain 10.89 dB Q 0.41
Filter 2: ON PK Fc 186.20 Hz Gain -3.73 dB Q 0.84
Filter 3: ON PK Fc 1251.83 Hz Gain -2.06 dB Q 2.42
Filter 4: ON PK Fc 2281.01 Hz Gain 2.91 dB Q 2.30
Filter 5: ON PK Fc 7028.68 Hz Gain 7.06 dB Q 1.11
Filter 6: ON PK Fc 5543.35 Hz Gain -10.97 dB Q 5.32
Filter 7: ON PK Fc 9368.73 Hz Gain 5.18 dB Q 1.57

View attachment 211598

Thanks for this EQ - it's great. It's quite different to the other two EQs I've been using, one of which is essentially Amir's, which sounds terrible compared to yours. One change I've made - which I make to all my EQs - is to have a sharp attenuation at around 10kHz as it seems I'm quite sensitive there; I hear a very sibilant/whistling sound with some female vocals, and flutes etc. Using CamillaDSP on moOde it's possible to toggle between EQs instantly and it's night and day.

 

[Paweł L]

Thanks for this EQ - it's great. It's quite different to the other two EQs I've been using, one of which is essentially Amir's, which sounds terrible compared to yours. One change I've made - which I make to all my EQs is to have a sharp attenuation at around 10kHz as it seems I'm quite sensitive there; I hear a very sibilant/whistling sound with some female vocals, and flutes etc. Using CamillaDSP on moOde it's possible to toggle between EQs instantly and it's night and day.

Did you try other EQs, say Oratory1990 EQ. While he boosts the 6-10kHz, he attenuates the area above 10kHz. It's also possible that your ear(s) creates resonance around 10kHz. I heard a few other people saying similar thing you mentioned with their hearing.
BTW, the older GRAS 43AG-4 has 13kHz resonance artifact while the newer 43AG-7 doesn't.

 

[threni]

Did you try other EQs, say Oratory1990 EQ. While he boosts the 6-10kHz, he attenuates the area above 10kHz. It's also possible that your ear(s) creates resonance around 10kHz. I heard a few other people saying similar thing you mentioned with their hearing.
BTW, the older GRAS 43AG-4 has 13kHz resonance artifact while the newer 43AG-7 doesn't.

Hmmm. I started with the Oratory one, years ago. I seem to recall there were two - he revised them all at one point? Also, in the last 5 years I've used 4 different headphones on 3 systems and some of them only support peak filters and one of them (moOde on the Pi Zero) didn't support PEQ at all. Since getting a Pi Zero 2 W (which supports Camilla) and having time off over xmas to fiddle a bit with that - and my other systems - I rethought my EQ and revisited this thread and am all-in on CamillaDSP.

I just added the Oratory one - specifically this one:

Dropbox

www.dropbox.com

and played with it for 30 mins or so. It certainly sounds good. (I had to drop the gain a little as it was clipping on some (admittedly pathologically bass heavy) music). I'll have to live with it for a bit and compare with "the Maiky one" to see if further changes improve things. I don't see an Oratory preset for the Zero2.

 

[Paweł L]

Also the newer Sennheiser pads used on 6** series are brighter than pre 2021 ear pads. They're stiffer so they don't affect the sound with time as much as the older ones. I don't know if Oratory revised the measurements for the newer pads. Solderdude posted the measurements comparison on ASR some 2-3 years ago, but he uses flat baffle, not the GRAS or the B&K. To me the 58X, 6XX with newer pads and Oracle EQ have definitely kind of brighter 'studio' sound, but to me this is way better than stock. Still way more enjoyable than stock Beyer house sound.
One of my problems is measurements provided for IEMs. Not only they differ from one reviewer to another due to different measurement method (tips, insert depth) but there are a few Harman curves introduced over the years (2019 V2 being the last one), I'm not counting the 'preference' curves. The biggest difference as with data measured by Crinacle is the adapter 711 vs B&K 5128 - some how I favour the later.

Crinacle's 5128 Graph Tool | Hangout.Audio

Compare graphs from the world's largest public database of ITU-T P.57 Type 4.3 IEM measurements, maintained by Crinacle.

graph.hangout.audio