Sennheiser HD 620S Headphone Review

[solderdude]

I was really interested in these. Not so anymore because the high level of distortion.

Up to 'comfortable loud levels' there is no audible distortion.
When playing really loud and you want clean sound you will need planars like Audeze, most dynamic drivers will distort at the same levels.
Not so healthy for the ears though.

 

[Arashi_Tsunade]

I find Amirm's measurements very different from these here:

maybe a defective model was used in this video?

 

[solderdude]

More likely the 'measurement system' was not up to snuff or he had a substantial leakage between the pads and the fixture.
Amir's measurements look like those of many others who measured one (or more).
No measurements look like the ones shown in the video..

This is what poor seal does to the sound:

 

[Arashi_Tsunade]

More likely the 'measurement system' was not up to snuff or he had a substantial leakage between the pads.
Amir's measurements look like those of many others who measured one (or more).

And so far we agree, you can find another video in the channel (provided you understand Italian) and the guy in question says he tried them and they sound terrible with a horrible sound signature. I don't know who to believe because there are many conflicting comments

 

[staticV3]

I don't know who to believe

Believe the industry standard measurements

 

[solderdude]

When you cannot get a proper seal (which can easily happen with this design) the bass is gone quickly and does not sound that well.
This is THE downside of the HD620S, I had to modify mine to get a good fit and good sound.
For some users there will be a 'gap' at the underside of the pads (towards the shoulders).
When this happens you can wear the headband a little more forward on the head so you can extend the sliders a bit more.

Some 'reviewers' don't like certain headphones or have an agenda.

You can always find both positive and negative reviews about any headphone (speaker, electronics and anything really too for that matter).

 

[oratory1990]

I find Amirm's measurements very different from these here:

maybe a defective model was used in this video?

The video shows a Neumann KU100 binaural microphone.
This is not an ear simulator, it does not have an acoustic impedance that matches that of the human ear.
it's a stereo microphone for binaural recordings (orchestras etc), it's not an ear simulator to measure the performance of headphones, despite looking somewhat like a human head
Its pinnae are very stiff (they essentially do not bend at all), which may prevent headphones from forming a seal against the "cheek". A very common issue when attempting to measure headphones with the KU100.
We have a KU100 in the lab, I'm very familiar with this issue.

 

[Arashi_Tsunade]

The video shows a Neumann KU100 binaural microphone.
This is not an ear simulator, it does not have an acoustic impedance that matches that of the human ear.
it's a stereo microphone for binaural recordings (orchestras etc), it's not an ear simulator to measure the performance of headphones, despite looking somewhat like a human head
Its pinnae are very stiff (they essentially do not bend at all), which may prevent headphones from forming a seal against the "cheek". A very common issue when attempting to measure headphones with the KU100.
We have a KU100 in the lab, I'm very familiar with this issue.

Thanks for the great explanation!

 

[isostasy]

I wonder how my ancient ancestor HD265s would compare?

I do hope listeners don't whack the volume up high, as their ears will suffer eventually (believe me, I KNOW!!!) and in any case, you can't physically FEEL the bass via 'phones

I have a flat-plate coupler (FPC) measurement of these headphones with HD6XX for reference. You can't compare this directly to other measurements, even those taken on other FPC rigs like solderdude's. Under 10kHz, however, you can see my HD6XX is usefully similar to his HD650 measurement to make some broad comparisons.

Solderdude said the HD620S "sounds very ‘open’ (as in not ‘boxy’) and isolates surrounding sounds decently good for a (passive) closed headphone." I would say the HD265 do have a bit of a closed in, boxy sound, and the isolation is not that good.

More than anything else you cannot purchase HD265 pads any longer. The HD620S pads look much better already, being a thick pleather material, whereas the HD265 used very thin and easily torn vinyl which does not feel nice. You can't match the sound with any 3rd party pads (I tried) so they're obselete once your pads die.

I sold my HD265 but would have hung on to them if I had a non-hifi need such as instrument practice where an open back wasn't suitable for whatever reason.

 

[Jeromeof]

I got mine Aune SR7000 today. I was looking for some good closed HP and this HD620S were on my list, but on the end I decide for Aune. From built quality & comfort standpoint Aune SR7000 are exceptional(compare to Hifimans I have). Out of the box sound is neutral, less punch in bass and not that harsh as Aryas Organic. To my surprise sounds more spacious than Sundaras. There is no too much arround them so far ,thus Im waiting on some meassurments. In tzhe meantime I will play with EQ.

Here are my initial measurements of the SR7000 - I might create a separate post for this as obviously this thread is for the HD620s:

Note: This was taken with a KB501X softear pinna with a 711 clone coupler

 

[Carlo2AC]

People who tried this the FiiO FT1, how do they compare? Interested to see a FiiO FT1 review here on ASR

Hard to get quality closed backs without spending a lot compared to just going IEMs

 

[solderdude]

The HD620S are ‘better sounding’ to me on my head but are finnicky in comfort and fit to me (had to modify the headband).

The FT1 are a lot bassier/warmer. They are also less finnicky and less ‘perfect seal’ dependent.

The HD620S has replacement parts and will have these for many years.
FiiO does not and not even sells pads.

When EQ’ed the treble quality of the HD620S is still a bit better.

The ‘problem’ with EQ is that it is based on a measurement on a specific fixture with a certain seal and done referenced to a specific target.
The fit of (either) headphone, your personal preference/ear/hearing may very well not adhere to the ‘standards’ that have been used to create the EQ so there is a big uncertainty factor here that may not be what you actually like/want.

The most similar to the FT1 (in tonal balance) is the audio-technica ATH-M50X. (similar but not the same)

 

[Carlo2AC]

How much more comfortable is the FT1 sir?

With regard to pads, considering how much they have been selling, I would be shocked if Brainwavz don't start getting pads for them, still different pads can affect the sound a lot

 

[solderdude]

The FT1 is much more comfortable.
Both in clamping force and feel on the skin.
HD620S is more suited for larger ears though.

I sold my FT1 ...
Prefer the HD620S and modified SRH-840A over it despite seriously liking the looks and build quality.
At least with Shure and Sennheiser I will have product support (original pads) for quite a few years.

 

[warpdrive]

too bad about the tight fit....most of the sennheisers are tight fitting on my big head, which is unfortunate because the sound is very good.

 

[Joachim Herbert]

How loud are you listening?

Thank you for pointing this out.

 

[Carlo2AC]

HD620S is more suited for larger ears though.

Okay i'm sold ahahahahaha

 

[Brianc]

Clamp is a bit less over time. With my longish but somewhat narrow head, the clamp is needed for a good seal. Also the earcups work well with my somewhat large ears. Have felt no need for EQ, but hope to find some non leather pads that are suitable. I prefer the HD650 sound and comfort, but I can't use them much because they're open back and my wife has supersonic hearing and works from home

 

[ShiZo]

@amirm Out of the Sennheiser closed-backs, this and the HD 300 pro are supposed to follow the harman target. If you get a chance, I'd try to measure the HD 300 pro too

 

[ehabheikal]

The sinad at 1khz is -74 or 0.019% at 94db
I used this https://sengpielaudio.com/calculator-db.htm
And visual estimates of distortion from the graph