Sennheiser HD620S Closed-Back Wired Audiophile Headphones

I had high expectations for the HD620S and it exceeded all of them.

I own the HD6XX and they’re incredible open back headphones, but I personally need closed back headphones most of the time. The HD620S is the answer!

This headphone has a neural response like all HD6-series headphones, but it has a little more low end and high end because it’s a closed back. So more bass, more treble… But it’s not bass heavy, and it’s not overly bright. It’s balanced. It’s just right.

Music sounds “the way it should” — but with more detail than what you would hear in the HD650 or HD6XX. However, it’s not the kind of detail some headphones add, where the treble is boosted to an absurd degree. Rather, it’s just there. It’s present.

The bass is the same. It gives you what you need without overshadowing the low mids.

This 6-series headphone uses a 5-series case, because Sennheiser found that the 5-series casing works better for closed back headphones… But it sounds like a 6-series.

No worries about the case, though — it’s very comfortable. I look like Alfred E. Neumann and yet my ears don’t touch the drivers at all!

One thing I noticed about this headphone was the sense of space. Usually closed-back headphones sound “in your head”, which is fine… But open back headphones have that ‘wide sound stage’. The HD620S is a little closer to open backs in that regard, but without the room noise.

As far as blocking external sound — the HD620S is about average in that regard, which is fine.

The cord comes out of only the left side (unlike the HD6XX which comes out of both sides.) This is a welcome upgrade. The cord is durable enough, but lightweight so there’s no sense of imbalance. It is slightly “microphonic” though, which is the wrong word but it’s what headphone people use. I’m talking about physical transfer of noise. If the headphone cable is tapping or moving, and nothing is playing in the headphones — you can hear it a little. Moreso than most professional quality/audiophile headphones… But not nearly as bad as the HD280Pro. It’s not a problem at all, but just something to be aware of. I don’t notice it at all during regular use, and I move my head a lot.

This isn’t a headphone you would want to use outdoors. The drivers have a very thin netting over them, which keeps out large debris but you wouldn’t want to use these in a dusty area. Think of these as home & studio headphones.

Speaking of studio — these are phenomenal for music production. They sound like studio monitors, basically, in the best possible way… Meaning they won’t make a poorly mixed song sound good — but a properly mixed song sounds detailed and amazing… With no noticeable peaks or valleys to make mixing confusing.

I would recommend these headphones for anyone who wants a reasonably affordable high end audio experience, or for audio engineers who need closed back headphones but want open back sound and quality.

In short, between the HD6XX and HD620S — these are the only headphones I need, and I’ve purchased (too) many before this. I love these headphones, and the HD620S in particular is my favorite.

I’m very happy with the sound of these headphones. Much improved low end compared to my HD 600s, without sacrificing mid to high frequency performance. The HD 620s is my new go to headphones.

I bought these headphones with excitement and anticipation only to be extremely disappointed. These headphones do not even sound as good as my hyperx gaming headphones. And they are so uncomfortable. I almost cried with how terrible my experience has been with my new headphones. I’m returning these sennheiser headphones. I hope the next pair of sennheiser headphones are much more comfortable and sound better than my hyperx headphones.

Comfortable and I prefer it’s tonality to the DT770 Pro’s.

These have a nice warm and full sound with a surprisingly wide soundstage for a closed back. I’ve been listening to them for a few days and they continue to amaze me. Sennheiser did a great job with these, they are becoming my preferred headphone! I really like the build quality and the comfort and cushion of the deep ear pads. To me, they are definitely worthy of the HD 6X0 series in terms of sound quality! I hope to get a balanced cable for them when that becomes available.

Yeah, you know who you are – one-size-fits-all except you – these are for you! Worth every penny in quality, comfort and size! My search is finally over – I have found a perfect headphones!
Looking forward to purchasing wireless model next!
5 STARS all the way!

PROS:
Great Mids
Nice feel around the head
Cable length is great

CONS:
So-So Treble
TERRIBLE Bass (unless you come from IEMs or Planars)

If you want to see HOW a closed ear headphone SHOULD sound, buy some Beyerdynamic DT770 Pro X or Pro (32 or 80 ohm) – these are overpriced and horrible comparatively

And yes, I own a pair of HD 650 – totally different and UNRELATED in every way except the Mids.

For those familiar with Sennheiser and its legacy in the audiophile industry, then you know the HD 600 series of headphones are legendary. HD 600 came out decades ago and still are considered some of the best cans you can get under 500 dollars. HD 650 is about 2 decades old, and they’re also very highly regarded. And the HD 660 pushes the 500 dollar price point, but it is also a newer very highly regarded set of headphones. These are all open back. When I saw these HD 620s, I became curious. Did Sennheiser produce affordably priced closed back cans that are deserving of a place in the HD600 family?

Short answer is no. These are definitely nice headphones, but there are some shortcomings. First, the bass. These headphones lack bass. The entire bass is understated, from higher bass to sub bass. There is little to no rumble in these cans. These do have a lot of high frequency presentation, but the highs are a bit veiled, as is the case with the signature Sennheiser sound. Highs lack detail. I’m very sensitive to Sennheiser’s veil, and these are no different. Where these headphones do shine is in the mid range. Vocals and mid-frequency instruments are front and center with these cans. Sound stage of these is comparable to the sound stage of HD 600 and HD 650s. Having the same sound stage as the HD 600s, an open pair of cans, you’d think that was a good thing, but HD 600 open backs are not really know for their sound stage. The sound stage is relatively wide left to right, but there is no depth in the sound stage front to back. The left and right sounds like it’s just outside of your ears, and the middle sound stage feels like it’s inside your brain. These do sound a lot like HD 650s in terms of sound stage, but just a closed back version.

As far as fit and comfort, these headphones have a lot of clamp force. Most closed backs will have high clamp force to enhance seal and bass delivery. These definitely seal well, but the bass doesn’t really benefit from the seal. They also tend to get very hot. The ear pads are thick and soft, and with the clamp and closed-back design, these get really hot.

I did an a/b comparison with my current favorite closed back headphones, Focal Elegia, which you possibly can buy for a price similar to these, and the Focal Elegia are heads and tails better. For Focal, bass is better, the highs are rich and vibrant, and the mids are balanced with the rest of the sound spectrum and textured. Everything I dont love about these HD620s are not an issue with the Elegias.

For audiophiles, there are not a lot of options for closed back headphones. There are a couple of manufacturers who have great offerings, like Beyerdynamics and Focal, but the really good ones are pricey. About $600+ for the higher end closed backs. In the sub $500 market of headphones, there are very few “audiophile” closed back offerings. So Sennheiser is filling a void in the industry for sure…but honestly, these aren’t much better than a much cheaper good pair of Audio Technica closed backs. Phillips even has a good offering in that 100-dollar price range. Although the HD 620s fill a price point in the market that is lacking, these really aren’t much better than the best 100-150 dollar closed-back headphones from Audio Technica or Phillips, if at all. To truly get audiophile caliber sound from a closed back, you have to jump up in price to about 600-1000. Maybe 500-800 during a sale. I like that Sennheiser identified a gap in the market, but I don’t love what they filled the gap with. These are good headphones for sure, but far from what I expect at this price or from something from the HD 600 family. Testing done with Fiio BTR7 via PCM/Bluettoth, Schitt Asgard/Bifrost stack, and Peachtree Integrated Amp.

I have very sensitive ears, and can’t stand wearing small headphones. IEMs are also hard to find because my ear canals are much smaller than my outer ears would suggest. After trying a bunch of headphones on at CanJam SoCal (a local headphone convention), I settled on these as the best and least expensive fit. I’ve had them for a while now, and while they were very tight in terms of clamp when I got them they are now nearly perfect. The sound is fairly good out of the box, although I am using Oratory1990’s EQ preset just for that last bit of fidelity (nearly every headphone benefits from EQ at least a little). They also seem to be well built, as expected from Sennheiser’s over ear headphones. The cable is decent, not exceptional but not a replace immediately type of cable either. Certainly it’s much better than their IEM cables!

I have owned many headphones and I place a premium on sound, comfort and value. This headphones sounds really good especially at this price point. I admit I really don’t like the looks but once it is on your head you can’t see it 🙂 It is comfortable and seems well made overall.

I recently purchased the more expensive ND20 closed-back headphones and I probably got a defective unt because it sounded quite poor. So I was a bit nervouse when I plugged this in and then pleasantly surprised with how good it sounded – FINALLY – a good value, good sounding heaphone.

Good job Sennheiser !