solderdude
Grand Contributor
HD300Pro has a very high clamping force, not really suited for longer listening session.
Treble is a bit hot.
Treble is a bit hot.
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Sennheiser HD 620S Headphone Review
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Hammeredklavier
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I'm quite a fan of them. They don't cost much, they sound very accurate with decent bass (subjectively, I haven't measured them), and importantly in my view, isolation is excellent. I don't see the point of closed headphones that don't isolate well. They're also easy to drive and you don't need to mess around with EQ.
They can get a bit sweaty after a while so perhaps not your top choice if you're going to wear them all day, and the utilitarian appearance won't be everyone's cup of tea. Great value though and I would say very recommendable for people who require accuracy and isolation. A bit of an unsung hero headphone!
I can be pretty sensitive and haven't noticed the clamping force. But that's just me, not sure how it interacts with other's heads. Are you going based on the graph I posted? If there was one thing that I would critique it would be it being a little bit strong in the treble. Do you have a closed-back headphone that you would suggest over the HD 300 pro? I have been looking and failing
Hammeredklavier
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They haven't got a particularly high clamping force - although I suppose it depends on the size of one's head! - but I suspect that cans that're designed for accuracy and high ambient noise attenuation need to seal well and not move around too much, because that tends to alter the response; they need to fit firmly. The main comfort issue I have with these is that the airtight seal created by the synthetic pads can leave you with sweaty ears after a long listening session, especially in hot weather.
If you're not too bothered about isolation then get HD600/650s (or open headphones of choice) - they're more comfortable. The only other headphone I personally own or have tried that offers similar acoustic isolation is the Neumann NDH20, which is more than twice the price of the HD300 Pro and is heavier. I suspect that objective measurements would find that the HD300 Pros had a more accurate frequency response, although they both sound plenty good enough to me.
I'm into sealed cans - I like and very much value high isolation. Most of us listen via computers these days, and they're noisy things. There're all manner of appliances and things in domestic environments that make intrusive noises... you have to wonder what's the point of having a DAC with 120 dB of dynamic range or whatever if you're going to listen in a noisy environment with open headphones!
solderdude
Grand Contributor
Specs say 6N clamping force (0.6kg on the side of the head) where as most headphones are between 2N and 4N.
Going off reviews and a few measurements I saw (HD300 pro)
Thought about buying one but it would end up in a drawer I reckon or would have to return it and burden sellers with return fees and opened boxes which I prefer not to do.
You could look into FT1 (and reduce the lows/warmth a bit if so desired).
Also modified/EQ'ed Shure SRH-440A and SRH-840A are not bad as a starting point.
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For any THD / SINAD results you have to also specify the level at which the measurement was taken. For lower sound pressures, THD will be lower.
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at 94
solderdude
Grand Contributor
1kHz is as good as the easiest frequency for a headphone to reproduce. Often distortion is at the lowest in that region. Also true for electronics b.t.w. one can get the best 'numbers' there.
Also as SINAD is noise and distortion and there is always some sound 'leaking' in (unless measured in a very silent box) and the measurement system also has some self noise the SINAD number at an arbitrary level is a completely pointless number for headphones and, just like in electronics, that number says nothing about sound quality.
And now something completely different..
I was recently sent a HD620S to check as the owner found it a bit 'weird' sounding.
As can be seen the left channel had 2.5dB more bass than the left channel.
After some experiments and checking for leaks etc. it turned out to really be something in the drivers.
No leakage in either cup.
My copy did not have this and looked most like the right channel.
Scrutinizing Amirs measurements I saw something similar.
About 2dB difference below 150Hz where the left channel is a bit higher in level.
It seems there are some QC issues or matching issues possible with this model.
Rtings measurements showed also around 2.5dB difference but in the mids and here the R channel was a bit higher.
This, as well as possible seal issues is something to keep in mind when shopping for a HD620S.
I have 2 other HD620S and both had good channel matching (within 1dB) so good ones exist but one might encounter one with some channel imbalance.
Also as SINAD is noise and distortion and there is always some sound 'leaking' in (unless measured in a very silent box) and the measurement system also has some self noise the SINAD number at an arbitrary level is a completely pointless number for headphones and, just like in electronics, that number says nothing about sound quality.
And now something completely different..
I was recently sent a HD620S to check as the owner found it a bit 'weird' sounding.
As can be seen the left channel had 2.5dB more bass than the left channel.
After some experiments and checking for leaks etc. it turned out to really be something in the drivers.
No leakage in either cup.
My copy did not have this and looked most like the right channel.
Scrutinizing Amirs measurements I saw something similar.
About 2dB difference below 150Hz where the left channel is a bit higher in level.
It seems there are some QC issues or matching issues possible with this model.
Rtings measurements showed also around 2.5dB difference but in the mids and here the R channel was a bit higher.
This, as well as possible seal issues is something to keep in mind when shopping for a HD620S.
I have 2 other HD620S and both had good channel matching (within 1dB) so good ones exist but one might encounter one with some channel imbalance.
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I checked the data on the unit I measured for channel mismatch and got roughly similar values, right channel is about 1-2 dB lower below 500 Hz. Nothing too drastic though.
Let me explain to specify what I mean by 'weird' sounding (it was my HP I sent to Solderdude):
it is a diffuse feeling of 'something is not quiet right', though tonality is not much comprimised (ok, lack of bass, compared to Harman). The channel mismatch would not explain this, it simply would move the stage more to left or right.
In direct comparison (AB) to what is hanging around here (Hifiman and Ultrasone), there is no significant difference at first sight/listening in respect of tonality.
But there is a subtile lacking of precision in soundstage and a subjective confusion of perception, not like reversed polarity, more like some phase shift of some degrees, that I never experienced with any of the dozen of HP I owned before, or the dozens of speakers I built and listened to.
Don't know if this might be the reason why some members are unlucky with this HP (as me), and if it could be clarified down by measurement.
solderdude
Grand Contributor
Maybe the 800Hz weirdness could account for what you perceived but the phase shift is rather small there.
The FR does have a sharp drop (almost 5dB) over a narrow band. It does not bother me though.
With the passive filter I made for the left channel it sounded like my own HD620S (green is filtered left channel)
The FR does have a sharp drop (almost 5dB) over a narrow band. It does not bother me though.
With the passive filter I made for the left channel it sounded like my own HD620S (green is filtered left channel)
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Carlo2AC
Active Member
I didn't expect channel matching to be an issue on a 350 U$ Sennheiser pair of cans, 2DB is well on the audible side even not on bassy tracks
solderdude
Grand Contributor
Yes, it probably has to do with tuning on the rearside of the driver being just fully closed and automated driver manufacturing. Both HD620S I have are well matched (within +/- 1dB)
Bump from 100 to 200Hz brings muddiness to sound, its very bad and ruin whole experience a lot. Its much worse than "ignored" seal problems on r70x review here, so even real bass "roll off" not even close as bad, as mentioned above FR "bump" on any headphone. Also build quality dropped down a lot on sennheiser side, its one of the worst now. (from big old companies)
I still can't get a way with sennheiser's clamping force in general, havent tried the HD300Pro but had the hd6xx series also tried the 5xx series all have it although it gets better with time. The HD800s is the comfiest one.
Might I ask a newbie question. I have looked on the web and here - and found some info but not I think relevant.
I have HD620S and want to import Amir's EQ settings into Wavelet for Android ( unless anybody wants to say otherwise?) as the 620 it is not in wavelet. I know wavelet needs a .txt format (?) but not sure how to convert from Amir's CSV file into the right format? Seems only one DB setting per frequency in Wavelet but Amir has separate l and R?
Is there an easy way to do this or am I being thick?
Thanks
I have HD620S and want to import Amir's EQ settings into Wavelet for Android ( unless anybody wants to say otherwise?) as the 620 it is not in wavelet. I know wavelet needs a .txt format (?) but not sure how to convert from Amir's CSV file into the right format? Seems only one DB setting per frequency in Wavelet but Amir has separate l and R?
Is there an easy way to do this or am I being thick?
Thanks
The CSV file is the frequency response measurement, not the EQ.
What I do is:
1. Open a squig.link tool like this
2. Go to the "Equalizer" tab --> click "Upload FR" and select the CSV file for the HD620S
3. Manually enter the EQ settings from amir's screenshot in the first post.
4. Click "Export Graphic EQ - Wavelet"
You can adjust the EQ filters or add more if you wish. Then each time you export the wavelet eq file give it a different filename so wavelet knows to import it as a new preset.
N.b. the type of .txt file that contains EQ filters would be like the one from Maiky76 attached here. With this one you click "Import EQ" in the squig.link app above, then "Export Graphic EQ - Wavelet" as before.
You can't import these directly into wavelet, it uses some other format.
Thank you. That is very helpful. I've made a start but fear I may be going down the rabbit hole..... LOL!
I tend to get hooked on this sort of stuff!
Thanks again
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