Sennheiser HD 620S Headphone Review

[adc]

The microphonic cable on the k371 is such a deal-breaker. It's that awful. Otherwise I love the cans, such a shame.

What is meant by "microphonic cable"?

 

[adc]

The measured channel imbalance in the lows (in the sample Amir tested) is most likely a seal issue (the wrinkles in the pads) and above 5kHz could be position dependent.

I concur. I just got my HD-620S, and they definitely are sensitive to position and seal.

And ... they are really good! As expected from this review, they are surprisingly neutral, and definitely the most open-backy closed-back phones I've heard. I'm impressed.

Not really that clampy at all to me, btw, but then I guess that's relative to one's experience. (The B&W P7, now THAT was clampy. )

 

[Doodski]

What is meant by "microphonic cable"?

The cable when rubbed with a hand, when rubbing against fabric, when tapped causes noise that is audible through the earphones. The noise can sound like a rubbing hash/fuzz sound and range up to a bassy addition to the audio. It is a major fault in headphones.

 

[solderdude]

What is meant by "microphonic cable"?

When you touch a cable or the cable rubbing on clothes or a desk you can hear that through 'mechanical' conduction of those sounds.
It depends on many factors:
How loud the music is playing (which can mask microphony)
How stiff the cable is.
Sheeting material (cloth is usually worse than smooth plastic)
The mechanical coupling between the connector/connection in the headphone and the internal structure of the headphone.

Some cables conduct mechanical sounds less than others. The trick Sennheiser uses in their HD490Pro cable for instance really works in reducing those sounds (a short coil in the cable near the earcup).

 

[adc]

The cable when rubbed with a hand, when rubbing against fabric, when tapped causes noise that is audible through the earphones. The noise can sound like a rubbing hash/fuzz sound and range up to a bassy addition to the audio. It is a major fault in headphones.

Oooooh - gotcha. Yes, I absolutely know that effect, and it is extremely irritating on some headphones. Sometimes I go so far as to put some kind of clip on the cable to secure it to my collar, which sometimes helps.

 

[Doodski]

Microphonic cable demo,>>>

 

[fragzone]

Oooooh - gotcha. Yes, I absolutely know that effect, and it is extremely irritating on some headphones. Sometimes I go so far as to put some kind of clip on the cable to secure it to my collar, which sometimes helps.

Fwiw, just a couple days ago I tried the method of tying a loop/simple knot at the top of the cable, which is far from elegant, but absolutely works and I'm much happier now given they are such good headphones in comfort and sound. The very top of the cable above is as microphonic as ever obviously (but if the knot is high enough it should rarely touch anything), but the bottom is tangibly less so, to the point I no longer notice it in day to day usage.

 

[Bernard23]

I concur. I just got my HD-620S, and they definitely are sensitive to position and seal.

And ... they are really good! As expected from this review, they are surprisingly neutral, and definitely the most open-backy closed-back phones I've heard. I'm impressed.

Not really that clampy at all to me, btw, but then I guess that's relative to one's experience. (The B&W P7, now THAT was clampy. )

I wish there was an objective review / test somewhere of the Yamaha HPH MT8s for comparison, the indications are similar characteristics but no reported issues with sealing.

 

[adc]

Fwiw, just a couple days ago I tried the method of tying a loop/simple knot at the top of the cable, which is far from elegant, but absolutely works and I'm much happier now given they are such good headphones in comfort and sound. The very top of the cable above is as microphonic as ever obviously (but if the knot is high enough it should rarely touch anything), but the bottom is tangibly less so, to the point I no longer notice it in day to day usage.

These are my solution: https://www.amazon.com/dp/B08BL44TW4

I bought those for a set of Radiosport ham radio headphones whose cable is the most infuriatingly microphonic of any that I've ever used. I couldn't even turn my head without drowning out content. To make matters worse, it is rigidly attached at an angle which makes it nearly impossible to avoid brushing my shoulder. Clipping it to the collar definitely helps.

Now that I know there's a term for it, it's even more maddening.

 

[Sebby]

I use the Hifiman Arya Stealth daily and wanted to pair them with closed headphones and was eagerly awaiting these HD620s.

After purchasing them, trying them out, I returned them after 10 minutes where the only thing I noticed was a terrible timbre and a headache caused by the clamping force. I found the high frequencies messed up on some tracks making them tiring, anemic bass (I tried every position) and some warmth in the mids that emerged without any logic and then went back to being anemic. Also the microphony of the cable was absurd.
Totally disappointed and bitter.

 

[Doodski]

the microphony of the cable was absurd.

Hmmmz... I was not expecting to read this! Bad bad bad...

 

[Sebby]

Hmmmz... I was not expecting to read this! Bad bad bad...

I hope I'm wrong, but it doesn't seem to be the cable that's the main cause.
One of the few qualities I've noticed is the excellent isolation from the outside and it seems that the structure that's very good at isolating is also the cause of the noise transfer. Just lightly touch the cups to feel how it amplifies even the most delicate touches.

I tried with another fabric cable connected only by one channel (the one I use on Hifiman) that always had zero microphony and although it improved, the noise was still present. It's not terrible if it rubs on a T-Shirt, but if you have a tracksuit with a zip, it creates a concert of noises.

 

[Bob from Florida]

I use the Hifiman Arya Stealth daily and wanted to pair them with closed headphones and was eagerly awaiting these HD620s.

After purchasing them, trying them out, I returned them after 10 minutes where the only thing I noticed was a terrible timbre and a headache caused by the clamping force. I found the high frequencies messed up on some tracks making them tiring, anemic bass (I tried every position) and some warmth in the mids that emerged without any logic and then went back to being anemic. Also the microphony of the cable was absurd.
Totally disappointed and bitter.

I own 2 of the 620S's and neither exhibit the sound qualities you mention. The clamping force eases with use. They have substantial bass and I find the sound balanced and non fatiguing. I do not use any dsp.

 

[Bernard23]

I use the Hifiman Arya Stealth daily and wanted to pair them with closed headphones and was eagerly awaiting these HD620s.

After purchasing them, trying them out, I returned them after 10 minutes where the only thing I noticed was a terrible timbre and a headache caused by the clamping force. I found the high frequencies messed up on some tracks making them tiring, anemic bass (I tried every position) and some warmth in the mids that emerged without any logic and then went back to being anemic. Also the microphony of the cable was absurd.
Totally disappointed and bitter.

I too have a different experience, I do use EQ but not much and mostly to eliminate the mid bass hump. I have no problems with the cable either. Sounds like you have a sealing issue if the bass is anaemic in its presentation.
What did you mean by a terrible timbre and an illogical warmth? Intrigued by what you observed.

 

[Sebby]

I own 2 of the 620S's and neither exhibit the sound qualities you mention. The clamping force eases with use. They have substantial bass and I find the sound balanced and non fatiguing. I do not use any dsp.

I'm glad you like them. Of course I'm "exaggerating" my feelings to describe them, but as I write I'm scrolling through my playlist and my feelings remain (I reopened the box, since I started the return but will deliver them tomorrow morning).
To get good extended bass I have to take off my glasses and push the pads further with my hands. There are tracks where the sound actually seems good, others where it even seems warm and others where it seems thin. Sometimes these differences emerge in the same track. There are passages where for a moment a warm sound emerges and then goes back "sterile". It seems like headphones without a well-defined character but that change depending on the frequencies emphasized in the various passages of the track. There are tracks where the highs are emphasized and it loses control, making undefined and separated highs emerge, making them tiring.
I can only partially solve it by lowering the volume, but then I find myself without deep bass. I found the sense of spaciousness of the soundstage beyond my expectations, although not very precise and flat, and it does not give me a sense of oppression, which is good for me. Maybe I expect too much from closed headphones, but that's how I feel. Also, as I finish writing, the huge discomfort just in front of the jaw joint is resurfacing to the point of becoming unbearable. You are right that with time it might loosen up a bit (how much and how is unknown), but I find this "philosophy" impractical for shoes, let alone for a pair of headphones. If they don't fit 95% well from the start, for me it makes no sense to beat myself up waiting for something to change after so many hours of use.
That said, each of us evaluates our own priorities. It's a shame because Sennheiser is a brand that I love (the IE600 are my absolute IEMs), but I have never gotten along with their Overears in terms of comfort or sound. I sold the HD600s a few years ago and I'm glad I did, but at least with the HD600s I had the patience to keep them for a year because they didn't cause me all these physical discomforts. When I read about the HD620s being closed HD600s, I was intrigued but, while they fixed some serious deficiencies of the HD600s, they created others because, at least as I recall, the HD600s still sounded a bit better overall and again, despite their deficiencies

 

[Bob from Florida]

I'm glad you like them. Of course I'm "exaggerating" my feelings to describe them, but as I write I'm scrolling through my playlist and my feelings remain (I reopened the box, since I started the return but will deliver them tomorrow morning).
To get good extended bass I have to take off my glasses and push the pads further with my hands. There are tracks where the sound actually seems good, others where it even seems warm and others where it seems thin. Sometimes these differences emerge in the same track. There are passages where for a moment a warm sound emerges and then goes back "sterile". It seems like headphones without a well-defined character but that change depending on the frequencies emphasized in the various passages of the track. There are tracks where the highs are emphasized and it loses control, making undefined and separated highs emerge, making them tiring.
I can only partially solve it by lowering the volume, but then I find myself without deep bass. I found the sense of spaciousness of the soundstage beyond my expectations, although not very precise and flat, and it does not give me a sense of oppression, which is good for me. Maybe I expect too much from closed headphones, but that's how I feel. Also, as I finish writing, the huge discomfort just in front of the jaw joint is resurfacing to the point of becoming unbearable. You are right that with time it might loosen up a bit (how much and how is unknown), but I find this "philosophy" impractical for shoes, let alone for a pair of headphones. If they don't fit 95% well from the start, for me it makes no sense to beat myself up waiting for something to change after so many hours of use.
That said, each of us evaluates our own priorities. It's a shame because Sennheiser is a brand that I love (the IE600 are my absolute IEMs), but I have never gotten along with their Overears in terms of comfort or sound. I sold the HD600s a few years ago and I'm glad I did, but at least with the HD600s I had the patience to keep them for a year because they didn't cause me all these physical discomforts. When I read about the HD620s being closed HD600s, I was intrigued but, while they fixed some serious deficiencies of the HD600s, they created others because, at least as I recall, the HD600s still sounded a bit better overall and again, despite their deficiencies

I seem to recall @solderdude saying that he bent his a bit to reduce the clamping force. Headphones can be very subjective due to head shapes not matching and wearing glasses. It is always possible you received a pair with a technical issue.

 

[Salt]

After I had tested my first sample by @solderdude (see above), because it sounded weird, and had sent them back and received a new one, I'm totally satisfied. The sound is as to be expected and microphonic influence by wire is low, but this might be due to afterbuy balanced cable I use.
I made one personal experience with these HP: one can drive them loud without any audible distortions, but this does no good for hearing nor sound quality.
Just checked levels on foobar, and - 30dB up to -20 dB are in the range from smooth listening to all you can hear. Moving on it's becoming harder for ears and hearing, but not for the HP.

 

[Nspace]

I appreciate the effort to make a well-tuned closed back that doesn't cost an arm and a leg. I'd give HD620S a demo based on Amirs review. Still AKG K371 exists for less money with pretty good spatial qualities for a closed back, in my subjective opinion.

I was going to really take note of your recommendation since spatial cues are very relevant to most of the music I am involved with... until I came to see the effective measurement of comparatively high levels of AKG K371's absolute distortion.

Specially so, since these substantial higher levels of distortion are being produced at the sensitive area of 1,6 kHz to 11 kHz. Thus, those mentioned "spatial qualities" on those AKG's might very well be result of a forward amplification of sound artifacts, rather than a plain presentation of the original musical content...

Versus

 

[markanini]

Specially so, since these substantial higher levels of distortion are being produced at the sensitive area of 1,6 kHz to 11 kHz. Thus, those mentioned "spatial qualities" on those AKG's might very well be result of a forward amplification of sound artifacts, rather than a plain presentation of the original musical content...

Is there some comprehensive study of spatial effects perception being attributed to distortion artifacts in playback?

 

[adc]

Sorry for the non-sequitur, but the resurrection of this thread reminded me to add: I remain impressed with the sound of these things. There's is no listening fatigue at all; they seem superbly balanced and satisfying over all kinds of music. There is, however, one thing I hate: the earcups themselves are extremely microphonic. (Now that I have been introduced to the concept, I notice it a lot more than I used to). This isn't a big deal -- unless you are using them lying down in bed. Every tiny movement against the pillow echoes in these hollow plastic earcups.

Really unfortunate.