Sennheiser HD600 Review (Headphone)

[Robbo99999]

I have replaced my HD660s with HD600, I have to say that I am very surprised that HD600 sound so much better than the HD660s, the midrange and timbre are sublime and the treble smooth as silk, but what surprised me the most was that the bass was significantly cleaner with more slam than my HD660s, I drive them with RME ADI FS, and I love them so far.

That would be totally consistent with Oratory's measurements of the two headphones re the bass, and also the HD600 is better behaved in the treble too. I have never been able to understand any appeal for the HD660s as the measured frequency response is generally quite poor and it doesn't have angled drivers or angled pads that could help in the soundstage variable......so HD660s has always struck me as being a quite poor headphone........yes the HD600 doesn't have angled pads nor angled drivers, but it does have a really nice measured smooth frequency response that tracks a good target, and it's less bass shy than the HD660s too. (I own the HD600, but not the HD660s.....the HD600 is really nice to listen to at stock, although a tad bass shy, but I don't like the imaging and soundstage of the HD600, but there's no reason to think the HD660s would be better in those latter aspects, due to lack of angled driver & lack of angled pads, just like the HD600).

 

[Limopard]

I have replaced my HD660s with HD600, I have to say that I am very surprised that HD600 sound so much better than the HD660s, the midrange and timbre are sublime and the treble smooth as silk, but what surprised me the most was that the bass was significantly cleaner with more slam than my HD660s, I drive them with RME ADI FS, and I love them so far.

There is a reason that the HD 600 has been built since 1997 with only minor changes and the HD 660s already has a successor.

 

[isostasy]

These are on sale at Sennheiser UK.

View attachment 258261

EDIT: Aaaand they're gone! Out of stock.

Also £185 refurbished at times, though they're out of stock at the time of this post. If I didn't already have a HD6XX I'd probably opt for this considering the costs for importing to UK and the prices used copies go for.

Has anyone here measured or had any experience with Custom Cans modifications to the HD600 series? This one in particular:

HD600 / HD650 CNC Copper Mass loading mod DIY kit – Custom Cans Shop

jfunk.org

or is the same thing essentially just an EQ setting?

I agree with everything put by solderdude above, I have also measured the CC copper ring mod and to be clear, the ring by itself has little to no measurable impact on frequency response. It is not 'creating a longer port for tuning' as far as I can ascertain and I don't think this area behind the driver and magnet can be correctly described as a 'tuning port' to begin with, or at least I don't think there's evidence it serves that physical function by design (in this or any dynamic driver headphone in fact).

The different densities of foam do make a difference, however it's important to point out it's not just in the mid-bass, as the damping behind the driver also impacts parts of the mid-range:

That's an extremely exaggerated view, so to be fair this shows how minor the differences are:

Apologies, this was an older version of my measurement rig with very bad treble roll-off so doesn't look much like a measurement of a HD6XX should.

I'm not sure why the copper mod by itself, with no additional foam, shows very slightly higher SPL than stock between 3 and 4kHz: it's possible this is because I had to remove the headphone to install it, as I'm pretty sure I made the subsequent measurements without moving the headphones but by simply replacing the foam pieces with it on my rig (the grille was off the entire time). I'm sorry for this as obviously it lessens the value of the measurements.

My personal opinion on the copper mod and for that matter any other HD6x0 mod, including KISS, SBAF, and JAR, are:

1. I disagree with claims made about 'smoothing out the treble', which may be visible on certain measurement rigs, but are meaningless because though it may look like a slightly flatter line this doesn't mean 'flatter' acoustically. On a FPC or a miniDSP ears small peaks in the treble are almost meaningless and cannot be related to where peaks may occur on a human ear or rig with a pinna. Therefore simply having a measurement in which certain peaks appear flatter has no correlation to accuracy or sound quality. (This is besides the fact that my measurements didn't show any difference above 6kHz anyway).
2. Most of the time when you increase the damping behind the driver to reduce the bass, this also increases parts of the mid-range, notably 3-4kHz, as shown above. This area is either considered correct already or actually too prominent by most listeners, so you wouldn't want to increase it, thus rendering these mods worse than simply EQing bass if this is the frequency range you are really concerned with. In fact, any meaningfully changes in frequency response as a result of these mods can be replicated in EQ.
3. Any 'damping' performed on the plastic housing, i.e. just adding mass to the housing, is pointless, whether strips of dynamat or big chunks of foam.
4. Removing the plastic spider (the plastic ring holding the magnet in place) is pointless butchery. You're just damaging your headphones.
5. The Custom Cans copper ring adds weight, thus undermining one of the HD6x0 series positive attributes
6. Removing the stock foam behind the driver, held under the aforementioned spider, as recommended by CC, seems silly considering it is impossible to put back in. You wouldn't want to have less damping because you'd end up with too much bass, and if for some reason you want to add more damping you don't need a copper ring to do so.

I'm putting together some measurements right now of things you can try with items around your home, if you desperately want to 'mod' your headphones.

 

[isostasy]

As promised some measurements of my stock HD6XX with different 'modifications' (different rig so not comparable to above):

• 'taped 1/2 screen' is a strip of micropore tape behind the screen in the top half of the housing.
• 'folded cotton pad' was held in place by the grille, otherwise the dense foam and felt were simply cut to size to fit in the ~1cm hole in the spider

From this it's shown once again that some materials will bring down the bass but also bring up the mids around 3kHz. Not enough evidence to prove it here but it seems to be denser materials are worst offenders. Note the 'dense foam' fit pretty tight so is probably close to the worst case scenario of sealing off the driver completely.

If you are desperate to lower the bass on your HD6x0 without EQ, adding circles of felt to the mm or so of room behind the stock foam seems to achieve this without changing anything much above 500Hz.

One of the most interesting academically is the result of taping behind the silver screen. I don't know if it's the act of sealing this space, or the tape itself interacting with the sound waves coming back from the front of the headphone, but it measurably reduces the mids around 3kHz in a way some may find pleasant. Still, in EQ terms this is still only equivalent to about a 2dB decrease at 3.2kHz, Q between 1 and 2 maybe. I also have a HD265 Linear which is a closed back from the HD5x5 series, using the same housing as the HD6x0 series, and have found this taping behind the screen to be helpful tuning that because of the changes in frequency response from the closed back and pleather pads used.

If you're still interested, take a look at the comparisons I did with the same HD6XX driver in either the stock silver screened housing or old black paper screened housing. It's worth noting the different screen material has a much bigger impact than most of the modifications shown here. In fact @Limopard I might go so far as to say I disagree with you that the HD600 has seen only 'minor changes' as the three different screen materials used (black paper, black silk, silver screen) make more than a minor difference to the frequency response in my opinion. You could argue unit variation varies more than the change in screen material however.

Here's those measurements again but without the exaggerated view:

This may sound odd considering the praise these headphones get, but this is a way in which I think the HD6x0 series is under-rated. At least with the latest silver screen version, Sennheiser has probably done the best job possible with this combination of driver, housing, and pads. It's a great design which in my non-scientific background I think seems to rely on a very open front volume and completely open rear volume with limited impedance between them. The velour pads create enough of a seal to achieve an appropriate bass response, and that's it. No matter how much you fiddle with the rear damping or what pads you use, it's not going to get any better.

 

[Chris Kelly]

During the sixty days I had to compare them with the HD 560S because of Amazon's holiday return policy, I thought the HD 600 was lacking in the sub-bass register, had a subtle boost in the upper-bass register, and had a touch of sibilance somewhere in the treble register. For me, balanced sound takes priority over cosmetics. However, being that this is the HD 600 thread, in defense of the HD 600, I must say I love and miss the completely open-back metal housing and the completely flat ear pieces of the HD 600. The HD 600 would probably be the most balanced sounding Sennheiser headphones with those nice cosmetics.

 

[carsknivesbeer]

That is quite the reply and applaud the effort of measuring all the different foams and mods! It's really amazing.

I did end up getting the CC copper rings to try on the 3 different versions of the HD6xx I own. Part of it is testing myself to to see whether I can even hear a difference, kind of a test for myself. It was relatively inexpensive, repeatable, and consistent in use which appealed to me. I will spend some time with them and might end up with another cable from SoldierDude instead. I do EQ using both premade and custom EQs from Soundsource. Having this kind of information is very valuable and is the point of ASR so do know your work is appreciated.

 

[MiloTheFirst]

I have replaced my HD660s with HD600, I have to say that I am very surprised that HD600 sound so much better than the HD660s, the midrange and timbre are sublime and the treble smooth as silk, but what surprised me the most was that the bass was significantly cleaner with more slam than my HD660s, I drive them with RME ADI FS, and I love them so far.

What a coincidence, after years of owning the hd660s I finally bought a pair of HD 600 a week ago. however I didn't reach quite the same conclusion

ever since I bought the 660s I had more than a few grievances, the treble was too subdued and the soundstage was narrower than I expected, however I also really liked how natural acustic instruments sound and while the bass was weak it seams clean and with good speed to me. listening to vlogs and movies with the 660s is a joy, and they generally pleasant with pop music even with the stock sound signature (of course EQ makes them a lot better) however they fail miserably with orchestral sounds tracks.

but then I found a pair of used HD 600 almost like new for 180€ and decided to give them a chance. since my main complain with the 660s is the lack of treble I thought this would leave me satisfied, and let me close the page on the HD6X0 journey and finally be able to call myself a true audiophile ™.

jokes aside, after having AB tested them for a week, while I completely agree that the 600 have better stock tuning, I can see why Sennheiser considered the 660s an upgrade when they were released. I believe that the 600 are very well balanced without EQ and provide a pleasant laid back experience with any genre, however it inmediately came to my attention how much more natural strings and vocals sound on the 660, I thought the 660 had narrow "soundstage" but the 600 feel somewhat clutered in comparison. for the first point I think it really is just a result of using a more developed driver, and for the second point I think the better perceived instrument separation is just a result of the HD660 having less prominence in the lower midrange

I think that with EQ the 660s are a tier above the 600 and finally owning the later made my appreciate the former a bit more

that been said, with my current knowledge. at the original release price of 500€ for the 660s vs the then usual 300€ of the 600, I don't think there is a competition , I would recommend the HD600 100% and would have bought it instead had I know (I had bought my 660s at 400€ though). However, now a days the 660s stay around 350€ at Amazon Spain, and at that price it becomes a lot more appealing If you are confident about your EQ skills.

 

[solderdude]

Here's damping differences for HD58X using a felt disc behind the magnet hole which had various diameter holes in it. (1dB scale)

The rear damping also affects 4kHz.

This was different when using different kinds of damping materials, (felt, foam)

There was some some influence but not as much as damping using the felt disc with hole

 

[rcstevensonaz]

I bought my pair around 2000. I was not and am still not a headphone guy. I bought them based on reputation. I had never seen a pair and when they arrived (mail order purchase) I was horrified by the hideous speckled paint finish. Initially I wondered if I had been ripped off by the mail order firm. A few moths later I was at a trade show and saw that the Sennheiser demo had a similar pair. I asked if there were alternative finishes and was greeted with a look of surprise.

I guess in Germany around 2000, that speckled look was considered cool. Mine have mostly lived in a drawer and rarely come out to play. It isn't because they are ugly or sound bad, I just rarely need a pair of cans. When I do wear them the good news I can't see them and they sound pretty good.

If yours are just slightly used, drop me a note if interested in selling them. My pair of the era are pretty beat up from daily use and the (too frequently) occasional getting knocked to the floor when not in use and the cable gets caught by my chair.

 

[Mr. Widget]

I wish I could help. They are mint and I have even kept all of the original packaging. Unfortunately I use them every so often mostly for testing or verifying something and would just need to replace them.

Just yesterday I noticed a headphone jack on a piece of gear. I read the sales hype on the piece which bragged about having an internal class A amp capable of driving any headphones down to a 32 Ohm load. I plugged my HD600s in, played a few of my favorite cuts and waited for the magic to happen. I was still underwhelmed.

When I play these cuts through my speakers I get goosebumps... through the cans I felt like I was analyzing the music not being enveloped and moved by it. I guess I am just not a headphone guy.

 

[rcstevensonaz]

I wish I could help. They are mint and I have even kept all of the original packaging. Unfortunately I use them every so often mostly for testing or verifying something and would just need to replace them.

Just yesterday I noticed a headphone jack on a piece of gear. I read the sales hype on the piece which bragged about having an internal class A amp capable of driving any headphones down to a 32 Ohm load. I plugged my HD600s in, played a few of my favorite cuts and waited for the magic to happen. I was still underwhelmed.

When I play these cuts through my speakers I get goosebumps... through the cans I felt like I was analyzing the music not being enveloped and moved by it. I guess I am just not a headphone guy.

No worries. But should you ever decide you want to replace those with something else, drop me a note. The HD600's are my daily workhorse headphones.

 

[Limopard]

I bought my pair around 2000. I was not and am still not a headphone guy. I bought them based on reputation. I had never seen a pair and when they arrived (mail order purchase) I was horrified by the hideous speckled paint finish. Initially I wondered if I had been ripped off by the mail order firm. A few moths later I was at a trade show and saw that the Sennheiser demo had a similar pair. I asked if there were alternative finishes and was greeted with a look of surprise.

I guess in Germany around 2000, that speckled look was considered cool. Mine have mostly lived in a drawer and rarely come out to play. It isn't because they are ugly or sound bad, I just rarely need a pair of cans. When I do wear them the good news I can't see them and they sound pretty good.

They ditched the old look for the 2019 redesign. Now it's a quite classy grey metallic.

 

[Mr. Widget]

They ditched the old look for the 2019 redesign. Now it's a quite classy grey metallic.

I'm surprised it took them 19 years to realize how grotesque they looked. They are certainly well made and quite comfortable. A simple satin black finish would have gone a long way to improving the look. Gray metallic doesn't sound bad either.

 

[isostasy]

I'm surprised it took them 19 years to realize how grotesque they looked. They are certainly well made and quite comfortable. A simple satin black finish would have gone a long way to improving the look. Gray metallic doesn't sound bad either.

You can get satin black! .... if you get the fairly different and more expensive HD660S instead. I don't know why Sennheiser forces your choice of model to dictate the colour you get. The navy paint on my HD6XX is so dark it looks almost black under all but the brightest light, however.

 

[Leporello]

I'm surprised it took them 19 years to realize how grotesque they looked. They are certainly well made and quite comfortable. A simple satin black finish would have gone a long way to improving the look. Gray metallic doesn't sound bad either.

I am on my second pair now. It has the new look which I find quite stylish. But I sometimes miss the grotesque look of the first pair (sold to a friend years ago).

 

[sharock]

Do you guys listen to your headphones whilst looking in the mirror or something?

 

[Robbo99999]

Do you guys listen to your headphones whilst looking in the mirror or something?

Ha, I agree, I couldn't almost care less for aesthetics in headphones. (comfort and sound are what's important to me & value)

 

[IAtaman]

Do you guys listen to your headphones whilst looking in the mirror or something?

No, but they are not purely functional devices either, so the expectation that they look good is not unwarranted.

 

[Emlin]

No, but they are not purely functional devices either, so the expectation that they look good is not unwarranted.

If they are not purely functional then why not?

I think you have a circular argument going on here.

 

[IAtaman]

If they are not purely functional then why not?

I think you have a circular argument going on here.

Sorry, not sure what is circular. They are not purely functional, i.e. they are not just sound reproduction devices, therefore it is OK to expect them to look good. What am I missing?