Reference Headphones – a journey

Everyone knows this question: is this, what I’m hearing, the thruth? We all know that most listening situations suffer from imperfect speakers or rooms. The good and the bad news are: nothing will ever be perfect. Headphones allow us to listen to details in music, that speakers hardly reveal. Mostly because there is no room in the reproduction chain and the physical mass of transducers in headphones is low. Yet they have their own faults: the lack of crosstalk, reflections of our own body and ears and in-head localisation. Also it is not possible to move your head independently of the sound source. Mixing with consideration of the head related transfer functions could solve this and there are already lot of tools available, but this is another story.

For now we start at the very beginning: we go to a shop and listen to ‘our’ music on different headphones. We know this music very well, for some years we did listen to this outstandingly well recorded audiophile stuff in a lot of different situations, on different sound systems and in different moods. After a few hours we know: this are the best headphones around, we buy them and are happy. The journey could be over at this point. But still we ask: is this the thruth? I would like to quote a very good live mixer, Prof. Matthias Reusch, on his headphones: “Ich habe über die Jahre zwei Kopfhörer gefunden, die meinen ganz persönlichen Klangerwartungen gut entgegenkommen. Das heißt, wenn mir das Ergebnis auf diesen Kopfhörern gefällt, dann stimmt es in den meisten anderen Abhörsituationen.” (“Over the years, I have found two headphones that meet my very own sound expectations. That means, if I like the result on these headphones, then it is true in most other listening situations.”) I hopefully will be at this point soon, but for now: lets do some more steps.

As an audio professional I actively listen to sound events every day. I try to be preferably objective und assess them. The headphones should be neutral in the most positive way: reveal anything and add nothing. They should be ease to listen to for many hours. To find a suitable pair of headphones I read every scientific paper about headphones that I could find in the last month. As an starting point I can recommend searching for publications of Dr. Sean Olive. Listen to him in this youtube video. I also like Innerfidelity, DIY Audioheaven, Superbestaudiofriends, gearslutz and there are more.
If you want to buy one of the best headphone preamps avaible for little money, go buy the Objective2 designed by NwAvGuy.

Reading is one thing, but listening is clearly another. Therefore I took my personal reference music and a dummy head and went to the headphone dealer of my trust. I’m located in Frankfurt/Europe and this is the right moment to express my gratitude to Hifi Profis for their support.

Support your local dealer! Thank you guys.

I completed this test in three steps:
1. Listen to headphones, which are recommended by the internet community and colleagues
2. Measure them with a dummy head
3. Listen again

In the following I will describe my personal impressions of the tested headphones, tell about the measurement setup and post the measured frequency responses. I will provide the measurement data, so anyone can make her or his own conclusions. Well, actually you need to listen for yourself. Especially considering that each ear is shaped differently and auditory canal resonances can vary significantly. Congratulations: you are unique 🙂 More about this from David Griesinger here.

The headphones tested were the following:
AKG K 812
Audeze LCD 2
Beyerdynamic DT 770 Pro
Beyerdynamic DT 1990 Pro
Focal Clear
Focal Elear
Neumann NDH 20
Sennheiser HD 600
Sennheiser HD 800 S
Sennheiser HD 820

Additionally I tested further headphones. They are out of competition because they are not portable 😉 Though, for stationary applications they are absolutely suitable.

Sennheiser HE 1
Stax 3100
Stax SR 007
Stax SR 009
Stax SRS 5103

Due to my limited time I did not measure and listen to each and every of these headphones. Therefore, the descriptions are partly incomplete – feel free to complete them on your own. As measurement equipment I used a Neumann KU 100 dummyhead, a RME Fireface UC and the software Room EQ Wizard. Thanks John, you are the best! The volume during the measurements was at a level I would normally listen to , but it is not calibrated. Nor is the soundcard (disclaimer off).
For each single measurement I took the headphones off the dummy head and placed them back on again. The graphs shown further down are averages without smoothing. My personal reference music is Amanda McBroom, Jennifer Warnes, Donald Fagan, Chris Jones, Rage Against the Machine, Bassnectar and some more stuff. What is your reference music and why? Please write to me

Now let’s go for it…

AKG K 812

AKG K 812

The K812 have a good bass range, too much highs, like sss and fff sounds. They sound similar to the HD800S, but less distant. They are a little hard in the higher mids and the brass sounds too much äää (babbling?squawking?).

Audeze LCD 2

Audeze LCD 2

The LCD 2 are balanced over the complete frequency range, have very good impulse behavior and rooms are pictured very well. They have a little less rooms than the HD800S.

Beyerdynamic DT 770 pro

No measurement done for these. Yet, from listening I feel too less bass, too much highs. Rooms are ok, they sound a little blurry.

Beyerdynamic DT 1990 pro

DT1990 EQ Curve

Also no measurement for these headphones, though. I own them since a few month. Actually, I use this EQ when listening to them (not very often). Do you have them, too? What do you think about this EQ curve? Please let me know. They show rooms very good, have too much highs and too less lows.

Focal Clear

Focal Clear

The Clear sounds balanced and brighter than the Audeze LCD 2. They have plenty of bass and less highs than the HD 800S.

Focal Elear

Did not spend much time on them, because I prefer the Focal Clear.

Neumann NDH 20

Neumann NDH 20

I am biased towards these headphones, because I bought them some days ago. My first impression was: oh, too much bass. The sound of ööö is too much, lowmids are (a little) blurry. You can find resonances around 40Hz without measurements. After longer hours and days of listening I think: these are good headphones. They are very picky about the positioning on the ears. Guess I can accept them for a while.

Sennheiser HD 600

Sennheiser HD 600

They are direct and very neutral. The sound is a little on the warm side. Rooms are not as good as with other tested headphones. They are more distant than the LCD 2.

Sennheiser HD 800 S

Sennheiser HD 800 S

These headphones are true classics. They have super resolution and for my taste a little too much highs. Not as easy as the LCD 2 or the Clear and less bass than these.

Sennheiser HD 820

Too much highs, I’m not that old yet 😉 In terms of resolution they sound like the HD 800 S, very good.

Sennheiser HE 1

Sennheiser HE 1

Very, very rich in detail. Never heard something like this before. The sound is absolutely enjoyable with its subtle warm distortion. The preamp that comes with these headphones is impressive with its marble and the schnickschnack when starting up. They play easily, like HD 800 S with better highs. Too bad I broke them during the test. Just kidding. Go buy them. No, wait, go here

Stax SR 009

Stax SR 009

I can’t really remember what they sounded like, uhm, only that they are very good, top notch. If you want to know: go to your local dealer! Hifi-Profis

Stax SR 007 and other Stax headphones

Stax SR007

I provide some more measurements of Stax headphones further down. For less than 1000€ you can get a very very good headphone and preamp, that will make you happy for the rest of your life.

Conclusion

For critical listening I would prefer the Audeze LCD 2. Second the Focal Clear. If you don’t travel with the headphones it can be a Stax. For enjoyment it will be the HE 1, man, so much details… If you want to take a closer look at the measurements you can download them here

The file is a .zip, you can unpack and will have a .mdat measurement file for Room EQ Wizard. The password (with special character) to unzip is:
https://www.effectivealtruism.org/