Kennerton Rognir Review (Closed Back Headphone)

[vkvedam]

There's plenty of EQ software to choose from for smartphones and tablets. And then there's the Qudelix-5K for hardware PEQ.
These days, there's no good excuse for not equalizing your headphones.

That doesn't work, I stream my music through CCA and DLNA renderers. Can't have the phone plugged in like a PC plus this enables bit-perfect playback.

 

[TabCam]

It is more than double the work. The measurement pipeline just doesn't support it.

I create the EQ in Roon player. There is no exporting of that EQ and even there were, it would be a pain to reimplement it in Audio Precision as a filter. The only way to then measure the impact is to run an asynchronous test where Roon plays test tones and AP captures it. It can be done and I have done it but it is really a pain.

Ultimately the purpose of my EQ is to show whether the frequency response measurement artifacts are audible and to what extent. I am building a closed loop of listening with measurements. It is not meant to be a 100% precise inverse correction of frequency response error but rough approximation.

Can't you make and use digital audio files of the test tones/sequences, EQ those (could be automated and then use the EQ-ed test tones/seqiences for measuring?

 

[amirm]

Can't you make and use digital audio files of the test tones/sequences, EQ those (could be automated and then use the EQ-ed test tones/seqiences for measuring?

Yes but then Audio Precision doesn't control the timing of when the test tone is run. You have to start one, then start the other and play around until the two sync up. As I said, it can be done and I have done it but it is just not fun work when the results are obvious. Any change made to frequency response in EQ obviously changes the same measurement.

 

[pozz]

Here's @amirm's target curve, measurements of this headphone and his filters.

Less of a mystery when looked at this way.

Again with psychoacoustic smoothing:

 

[gvl]

Yes but then Audio Precision doesn't control the timing of when the test tone is run. You have to start one, then start the other and play around until the two sync up. As I said, it can be done and I have done it but it is just not fun work when the results are obvious. Any change made to frequency response in EQ obviously changes the same measurement.

Can you script it? I thought AP software has some sort of scripting API.

 

[pozz]

View attachment 159711
View attachment 159712

Here's @amirm's target curve, measurements of this headphone and his filters.

Less of a mystery when looked at this way.

Again with psychoacoustic smoothing:
View attachment 159713
View attachment 159714

@amirm Nice work just by using your ears.

 

[Zensō]

Head-fi thinks the Rögnir is much better than the Stealth.

Head-fi also believes in silver wire and pixie dust.

 

[nyxnyxnyx]

I see that some of you are a bit inconsiderate in some aspects.

There's nothing wrong with headphones at $$$$ range trying to *look* or *sound* different. In fact, I think they have to stand out in at least an area because otherwise there's not much of a reason for people to feel attracted and buy them, even when it comes from a more-boutique, less-achieved brand like this company. So the attacks on the cups, headbands, etc... are uncalled in my opinion, especially when they seem to be premium components.

What we should criticize besides objective measurement is how unimpressive it performs in its original form (no EQ). I know DSP can save or improve a lot of things but it also hints that the people creating headphones either didn't consider their sound signature enough, or they expect us to EQ it and be happy or a combination of both and other things as well. In the end, if the headphones simply require EQ to sound good to the mass (or a portion of seasoned listeners), then it's just not so convincing.

Lastly, some of you complain about the price and how Amir recommended it with EQ. Price has different relevancy here as always, the conclusion had always been based on performance and he was honest about his subjective impression. As for the price, we all know products this expensive must be somewhat overpriced and considered luxurious. We definitely don't need a 3k headphones, and the people who buy them are either looking for the last percent they subjectively think they missed, or just have too much money to spend on headphones.

Think of headphones like this as a luxurious and exotic item, and the value it contributes is not the actual performance, but the joy those hobbyists have based on having rare, unique headphones (although it might sound really bad).

 

[TabCam]

Yes but then Audio Precision doesn't control the timing of when the test tone is run. You have to start one, then start the other and play around until the two sync up. As I said, it can be done and I have done it but it is just not fun work when the results are obvious. Any change made to frequency response in EQ obviously changes the same measurement.

Thanks for explaining. testing is always difficult and the devil in the details. Would be nice if the AP worked with a sync signal to make that kind of automation possible. The more that can be automated, the better!

 

[GWolfman]

Ouch (looking at the price tag)!

 

[Zensō]

I see that some of you are a bit inconsiderate in some aspects.

There's nothing wrong with headphones at $$$$ range trying to *look* or *sound* different. In fact, I think they have to stand out in at least an area because otherwise there's not much of a reason for people to feel attracted and buy them, even when it comes from a more-boutique, less-achieved brand like this company. So the attacks on the cups, headbands, etc... are uncalled in my opinion, especially when they seem to be premium components.

What we should criticize besides objective measurement is how unimpressive it performs in its original form (no EQ). I know DSP can save or improve a lot of things but it also hints that the people creating headphones either didn't consider their sound signature enough, or they expect us to EQ it and be happy or a combination of both and other things as well. In the end, if the headphones simply require EQ to sound good to the mass (or a portion of seasoned listeners), then it's just not so convincing.

Lastly, some of you complain about the price and how Amir recommended it with EQ. Price has different relevancy here as always, the conclusion had always been based on performance and he was honest about his subjective impression. As for the price, we all know products this expensive must be somewhat overpriced and considered luxurious. We definitely don't need a 3k headphones, and the people who buy them are either looking for the last percent they subjectively think they missed, or just have too much money to spend on headphones.

Think of headphones like this as a luxurious and exotic item, and the value it contributes is not the actual performance, but the joy those hobbyists have based on having rare, unique headphones (although it might sound really bad).

Yup. There’s no rational reason any headphone should cost this much. These are clearly a Veblen good designed with the intention of signaling wealth. Like all Veblen goods, the perceived value of these types of headphones increases as the price increases, regardless of the level of performance and engineering in the product. Most often, as we’ve seen with many so-called “summit-fi” headphones, there is little correlation between price and actual performance.

 

[GimeDsp]

Quite interesting that EQ could make such a big difference.

I know in pro sound things like Line arrays depend heavily on DSP to sound good. Without DSP large array hangs would sound like mumbled garbage.

It's interest that EQ, time delay, DSP used in complex systems is seen as a necessity to make them sound good while simple EQ in headphones, even expensive ones, is looked at as a cardinal sin.

large systems need DSP, room correction/DSP is now looked at as a plus for hifi, looks like for headphones it's still a sin, the final frontier must be IEM!

PS-if a person can spend $80,000 on a gaudy watch, $300,000 on mono block amps, they can get these and use EQ.

 

[PeteL]

Quite interesting that EQ could make such a big difference.

I know in pro sound things like Line arrays depend heavily on DSP to sound good. Without DSP large array hangs would sound like mumbled garbage.

It's interest that EQ, time delay, DSP used in complex systems is seen as a necessity to make them sound good while simple EQ in headphones, even expensive ones, is looked at as a cardinal sin.

large systems need DSP, room correction/DSP is now looked at as a plus for hifi, looks like for headphones it's still a sin, the final frontier must be IEM!

PS-if a person can spend $80,000 on a gaudy watch, $300,000 on mono block amps, they can get these and use EQ.

But how many times have you seen a boost of 9 dB at Q 3.0 applied to fix a PA reponse? I am not saying such a cut to notch out a standing wave, but to correct the response of the actual speaker. I like EQ, they are great and often necessary, but still don’t get how we’d want to purchase a bad sounding headset, based on the argument that everything is fixable at post. When there are many options that sound great untouched. Sure such a boost will sound better than the content just not being there, evidently, but really an EQ like this will add coloration of the signal. Also, EQ is not always possible for some use cases. Headphones manufacturers, if they design headphones with a clear intent, like PA speakers to need DSP to just be proper, they should advertise it as such and provide ressources to make that work IE compensation curves, and tool to use the headphone that way. This headphone has been released as a full completed product.

 

[Sal1950]

It's interest that EQ, time delay, DSP used in complex systems is seen as a necessity to make them sound good while simple EQ in headphones, even expensive ones, is looked at as a cardinal sin.

There is one big difference at play here, those other systems you compare with have the unknown X factor to deal with, the ROOM. All manner of FR changing factors play into what the listener hears when he is seated in the listening chair or at the mixing console.
Personally I feel as I must be missing something, I have no idea why we are being so forgiving to headphones that get designed with such an ugly response curve as this one.. We bang AVR DAC's over the head for having slight and likely inaudible failures in their SINAD measurements while working in an extremely noisy and interference swamped environment but will give the headphones a pass because they can be improved with some EQ, (notice I said improved and not corrected. My Senn HD 650s are far from perfect but no way in hell I would exchange them for these $4K pieces, I would call these broken, not flawed.
Amir I really believe we should tighten the criteria for headphone ratings.
YMMV

 

[WickedInsignia]

Those headphones reviews really puzzle me at times.

I agree, but I try to consider Amir's reviews as supplemental. They're usually a good test of a headphone's stock tuning to the Harman target and their raw technical prowess. His resumé indicates that he knows what he's talking about there, and even when things get subjective it's better than the flowery prose you'd find on a place like Head-Fi or most tech journal review articles.

Fortunately we have other points of reference. SolderDude, Crinical and Rtings make measurements and impressions, with Rtings having excellent test gear and the most reliable test criteria that undergoes internal review regularly.
Some people take issue with Rting's scores sometimes but they're so objective and thorough I don't think many are in a position to challenge them.

Sometimes it gets a bit "cult" here but that's like any forum. Enthusiasts are best served by acting as their own free agents and not tying themselves to any single source. Best to check out multiple reliable sources and average them to create a point of reference.

 

[GimeDsp]

This headphone style has weird styling.

 

[Maiky76]

This is a review and detailed measurements of Kennerton Rognir (Rögnir) closed back planar magnetic headphone. It was kindly purchased new by a member and drop shipped to me. Rognir comes in many colors but cost seems to be the same € 3,250 (US $3,770).

Clearly high quality material is used in construction of this headphone:

View attachment 159537

The look is a bit fussy for my tastes but you may think otherwise. Fortunately despite its weight this is a very comfortable headphone to wear for me:

View attachment 159538

The cups are round and have an inside diameter of 60 mm and depth of 22mm.

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!

It was not hard to fit the unit on the measurement fixture.

Kennerton Rognir Measurements
Let's start with our usual frequency response:

View attachment 159539

Whoa, what is this? Why such a chewed up response? I don't think I have ever seen so many variations at such low frequencies in a headphone. I had to filter the heck out of it to get some idea of what the response looked like:


View attachment 159540

Is it me or the ups and downs have a repeating rhythm from 200 Hz to 2 kHz? Anyway, not good no matter how you look at it including our relative frequency response:

View attachment 159541

Distortion at 94 dB is low but we need to boost the very area where it is the highest:

View attachment 159542

View attachment 159543

Every measurement points to the same acoustic disturbance including group delay:

View attachment 159544

Typical of planar magnetics, its impedance is flat and low:

View attachment 159545

Sensitive is a bit better than average:

View attachment 159546

So you should be able to drive it with many devices.

Rognir Listening Tests
I was listening to my every day Dan Clark Stealth before switching to the Rognir and boy did it feel like someone turned the lights off! Every bit of life got sucked out of music with no highs. The sound was flat and boring with no spatial effects. Given how bad the frequency response was, I was not hopeful that I could improve it much but I was wrong:

View attachment 159548

Every filter worked to pull up the performance of this headphone. The sum of those 5 filters transformed this headphone like nobody's business. Spatial qualities came back in spades and combined with thundering sub-bass, it was a delight to listen to it. Power handling is superb when driving it with my RME ADI-2 DAC, easily sticking a subwoofer in each of my ears as I turned up the volume for a second!

I was very surprised at the effect of the little filter at 880 Hz which I added at the end. It really improved clarity of the headphone and seemed to reduce its distortion.

Conclusions
Company says they designed their own driver which I guess is good. What is not good is that the design does not seem to have benefited from simple closed loop of measurements to identify the acoustic events that cause all the variations we have seen. Out of the box the sound is just not good for any level of money let alone what they charge. In a lucky turn of events however, equalization is superbly effectively in giving life to these headphones and making them quite worthwhile.

Out of the box, I cannot in any shape recommend the Kennerton Rognir. With equalization, it turns from a frog to a prince and so very acceptable and even great.

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As always, questions, comments, recommendations, etc. are welcome.

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Hi,

Here are some thoughts about the EQ.
Notes about the EQ design:

• The average L/R is used to calculate the score.
• The resolution is 12 points per octave interpolated from the raw data (provided by @amirm)
• A Genetic Algorithm is used to optimize the EQ.
• The EQ Score is designed to MAXIMIZE the Score WHILE fitting the Harman target curve with a fixed complexity.
  This will avoid weird results if one only optimizes for the Score.
  It will probably flatten the Error regression doing so, the tonal balance should be more neutral.
• The EQs are starting point and may require tuning (certainly at LF).
• The range around and above 10kHz is usually not EQed unless smooth enough to do so.
• I am using PEQ (PK) as from my experience the definition is more consistent across different DSP/platform implementations than shelves.
• With some HP/amp combo the boosts and preamp gain need to be carefully considered to avoid issues
• Not all units of the same product are made equal. The EQ is based on the measurements of a single unit.
• YMMV with regards to the very unit you are trying this EQ on.

Good L/R match.

I have generated one EQ, the APO config file is attached.

Score no EQ: 71.7
-> high because there practically no 10kHz trough making the both the standard deviation and the slope of the error much smaller than usual!
I guess this is one of these cases where the metric is tricked or the metric would need refinement, whichever way you want to look at the issue.
Score Armirm: 89.0
Score with EQ: 108.8

Kennerton Rognir APO EQ Full Flat@HF 96000Hz
October182021-112147

Preamp: -7.9 dB

Filter 1: ON PK Fc 25.73 Hz Gain 4.00 dB Q 0.70
Filter 2: ON PK Fc 122.05 Hz Gain -1.99 dB Q 1.35
Filter 3: ON PK Fc 210.99 Hz Gain 2.99 dB Q 2.00
Filter 4: ON PK Fc 400.59 Hz Gain -2.07 dB Q 2.94
Filter 5: ON PK Fc 568.71 Hz Gain 1.48 dB Q 3.68
Filter 6: ON PK Fc 856.36 Hz Gain -3.69 dB Q 3.17
Filter 7: ON PK Fc 1483.00 Hz Gain -1.99 dB Q 2.70
Filter 8: ON PK Fc 4125.31 Hz Gain 8.00 dB Q 1.46
Filter 9: ON PK Fc 13240.84 Hz Gain -5.82 dB Q 3.12

 

[amirm]

But how many times have you seen a boost of 9 dB at Q 3.0 applied to fix a PA reponse? I am not saying such a cut to notch out a standing wave, but to correct the response of the actual speaker.

Headphones are not speakers. They are able to absorb incredible amount of EQ boost. Speakers will fall apart if you push them remotely this hard. These things are sitting right next to your hear and are able to pump out massive SPLs. So at normal playback levels you are able to easily boost their response without worry.

 

[amirm]

Personally I feel as I must be missing something, I have no idea why we are being so forgiving to headphones that get designed with such an ugly response curve as this one.. We bang AVR DAC's over the head for having slight and likely inaudible failures in their SINAD measurements while working in an extremely noisy and interference swamped environment but will give the headphones a pass because they can be improved with some EQ, (notice I said improved and not corrected. My Senn HD 650s are far from perfect but no way in hell I would exchange them for these $4K pieces, I would call these broken, not flawed.
Amir I really believe we should tighten the criteria for headphone ratings.

Frequency response errors are directly audible and hence the reason they have such an outsized role in such measurements. And why EQ has the power it has: it is able to fix what ails these headphones. In some sense, this is no different than the headphone designer attempting to correct the same using mechanic, acoustic or electronic parts in the headphone. Why would one be superior to the other?

Once I EQ these headphones, they are often able to outperform some of the world's best speaker systems. How am I then supposed to say, "well it is still no good because I used EQ." The ultimate results are not the goal here? That is, great sound?

I have long separated the rate with and without EQ. So you can just stick to without EQ if you like but I firmly believe that is a mistake. EQ is needed in speaker systems for bass response. Its role there is much smaller than what it can do for headphones.

Finally, the ideal response of a headphone is more disputed than speakers. So I leave some allowance for a company thinking not complying with it is not a cardinal sin. To some extent anyway.

 

[GimeDsp]

For this money they should come with a gold plated DSP with diamond encrusted volume knob.

For listening to music I never use headphones, always as reference in studio/system tuning and evaluation type stuff, however the best I've heard was the HD650, which has great sound but very bass shy. Maybe these headphones EQ's would make me listen more the HP.