This is a review and detailed measurements of the Neumann NDH20 closed back headphone. It was kindly sent to me by a member and costs US $499.
The NDH20 is an attractive and solidly feeling headphone:
It weighs slightly above average but per above, it felt fine wearing it:
The removable headphone cable is light but has this spring action to it that was annoying. I literally had to put something on top of it on my desk to keep it from interfering with my mouse.
Note: The measurements you are about to see are made using a standardized Gras 45C. Headphone measurements by definition are approximate and variable so don't be surprised if other measurements even if performed with the same fixtures as mine, differ in end results. Protocols vary such as headband pressure and averaging (which I don't do). As you will see, I confirm the approximate accuracy of the measurements using Equalization and listening tests. Ultimately headphone measurements are less exact than speakers mostly in bass and above a few kilohertz so keep that in mind as you read these tests. If you think you have an exact idea of a headphone performance, you are likely wrong!
Fitment on the fixture was VERY difficult. It would not fully surround the artificial ear, and I could not get it to fully seal no matter what I did. Slight movements and changes would vary the levels but in practice, I noticed frequency response did not substantially change. Still, be on notice that my confidence in measurements are not super high (although EQ settings verified that they were good enough for that purpose).
Neumann NDH20 Measurements
Let's start with our usual frequency response:
I was quite surprised by this response. Given Neumann's heritage for neutrality in speakers, I expected a flat and bass shy response. Instead we have plenty of bass but then a suck out in the 1 to 3 kHz. We also have a deep cancellation around 2.6 kHz. I am not used to seeing such at such a low frequency. Relative response therefore shows somewhat a "V" response:
Distortion is very good considering that we don't need to boost the bass where it rises:
Something is definitely not right around 2.5 to 3 kHz though. We see the same in Group Delay:
It seems like a strong resonance of sorts out of phase with the response of the driver.
Impedance is middle of the road and mostly fixed:
Sensitivity is decent:
Headphone Listening Tests
First impression is not bad. You can hear the emphasis in bass and also some accentuation of highs. It is not until you dial in some EQ that you realize the imbalance:
I had to play a lot with these dials as the sound wound up being too bright after my initial correction. I was mostly happy with it but not quite there. It is possible some would prefer the heavier bass response.
Sub-bass response as you would expect is excellent.
Conclusions
This was a surprising outcome from Neumann. I expected a more neutral headphone but instead got a bass heavy one. Even though I am a fan of bass, it needs to be balanced relative to the rest of the response. I find that when the 1 to 3 kHz is sucked out, the sound becomes closed in which is a death sentence in my book for headphones as they already bad in that regard.
Equalization helps a lot but needs more refinement to get to a good place.
I can't recommend the Neumann NDH20 without EQ. With EQ, it barely gets there.
----------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
The NDH20 is an attractive and solidly feeling headphone:
It weighs slightly above average but per above, it felt fine wearing it:
The removable headphone cable is light but has this spring action to it that was annoying. I literally had to put something on top of it on my desk to keep it from interfering with my mouse.
Note: The measurements you are about to see are made using a standardized Gras 45C. Headphone measurements by definition are approximate and variable so don't be surprised if other measurements even if performed with the same fixtures as mine, differ in end results. Protocols vary such as headband pressure and averaging (which I don't do). As you will see, I confirm the approximate accuracy of the measurements using Equalization and listening tests. Ultimately headphone measurements are less exact than speakers mostly in bass and above a few kilohertz so keep that in mind as you read these tests. If you think you have an exact idea of a headphone performance, you are likely wrong!
Fitment on the fixture was VERY difficult. It would not fully surround the artificial ear, and I could not get it to fully seal no matter what I did. Slight movements and changes would vary the levels but in practice, I noticed frequency response did not substantially change. Still, be on notice that my confidence in measurements are not super high (although EQ settings verified that they were good enough for that purpose).
Neumann NDH20 Measurements
Let's start with our usual frequency response:
I was quite surprised by this response. Given Neumann's heritage for neutrality in speakers, I expected a flat and bass shy response. Instead we have plenty of bass but then a suck out in the 1 to 3 kHz. We also have a deep cancellation around 2.6 kHz. I am not used to seeing such at such a low frequency. Relative response therefore shows somewhat a "V" response:
Distortion is very good considering that we don't need to boost the bass where it rises:
Something is definitely not right around 2.5 to 3 kHz though. We see the same in Group Delay:
It seems like a strong resonance of sorts out of phase with the response of the driver.
Impedance is middle of the road and mostly fixed:
Sensitivity is decent:
Headphone Listening Tests
First impression is not bad. You can hear the emphasis in bass and also some accentuation of highs. It is not until you dial in some EQ that you realize the imbalance:
I had to play a lot with these dials as the sound wound up being too bright after my initial correction. I was mostly happy with it but not quite there. It is possible some would prefer the heavier bass response.
Sub-bass response as you would expect is excellent.
Conclusions
This was a surprising outcome from Neumann. I expected a more neutral headphone but instead got a bass heavy one. Even though I am a fan of bass, it needs to be balanced relative to the rest of the response. I find that when the 1 to 3 kHz is sucked out, the sound becomes closed in which is a death sentence in my book for headphones as they already bad in that regard.
Equalization helps a lot but needs more refinement to get to a good place.
I can't recommend the Neumann NDH20 without EQ. With EQ, it barely gets there.
----------
As always, questions, comments, recommendations, etc. are welcome.
Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/
