Kennerton Rognir Review (Closed Back Headphone)

[xykreinov]

You are the master of your own fate then. There are solutions with lower latency hits than good 'ole PulseEffects. @bmc0 have made one such solution for example, and I believe that the new EQ built into PipeWire may be of interest as well.

Oh interesting. Yeah, I was mainly being cheeky, I'm also really looking forward to what Pipewire brings. I'm sure everyone who's been complaining it was launched too early have forgotten what a nightmare PulseAudio was in early years.
Oh and btw, EasyEffects isn't PulseEffects anymore because it uses Pipewire. I've already noticed latency isn't as bad as it used to be by a good margin. Might do some tests later to see how low I can get it

 

[Robbo99999]

I am not sure that I can be more specific than what I already said. There is 9 dB of gain in a region where distortion is already in audible territory, and there is no evidence that the effect the EQ have on the phase response completely null the negative effect that the driver and physical considerations have on phase.

That's a problem with the headphone, not a problem with EQ.....re the distortion argument. There should be no concerns with using EQ with headphones, the only considerations are making sure distortion doesn't get out of hand which can be inferred from distortion measurments at different target dB (eg the 94 / 104 / 114dB that Amir does for instance), making sure you have enough amplification to run the headphone loud enough after applying negative preamps to cover the digital boosts, and you of course have to have an understanding of the innacuracies associated with headphone frequency response measurement the higher you go up the frequency range (as in the measurement becomes more unreliable so your EQ has to reflect that increased innacuracy by using wider filters and/or verifying by listening), but there's no problem with using EQ itself in headphones. EQ doesn't degrade quality of sound in & of itself, but it's only as good as the accuracy & relevance of it's implementation.

 

[GaryH]

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.

That's just due to the smoothing hiding the 10 kHz trough, it's there in the measurements. I'm sure if you use unsmoothed data the score wouldn't be nearly so high.

 

[xykreinov]

is there a way to see the post-eq frequency response chart?
because without it it's subjective.

Yes. If you want a good real world example, check out oratory1990.
Only downside to a second measurement is time. Which is fair, reviews are already extensive as is

 

[PeteL]

Ah I thought you were intimating that EQing will always have objective costs and artifacts. I see now you're only referring to this particular headphone and EQ.

Yes to any headphones that require such drastic correction. Now yes there is evidence that if purely and strictly on a signal , Equalisation don't strictly have effect on the frequency response: phase shifts, rigning, are technically forms of distortions, but you did convince me by Auratory's comment that in this particular case, meaning we are not worried about the signal itself but the reproduction of this signal and we are just partly reversing issues that where induced by the poor headphone, so I can accept that I was wrong by not taking that in consideration. As I said, the net result is a plus, not a minus.
Keep in mind that Oratory's comment was about debunking that linear phase is always better, not a firm statement that EQ don't produce artifacts.

 

[GaryH]

Yes. If you want a good real world example, check out oratory1990.
Only downside to a second measurement is time. Which is fair, reviews are already extensive as is

Those aren't post-EQ measurements on his pdfs, they're just the stock frequency response measurement convolved with the EQ curve to predict the post-EQ response. For the majority of headphones that don't exhibit any non-minimum phase behaviour this will be an accurate prediction. From the group delay plot it looks like this headphone may not be one of them though.

 

[thewas]

We should keep in mind though that not all measured deviations and headphones have minimal-phase behaviour, which can be better seen when the excess phase group delay is generated and correcting those with an inverse IIR filter will not (fully) correct the phase.

resourcesindex/where-to-find-headphone-measurements/minimumphase-csd-ir - headphones

r/headphones: A place for discussion, news, reviews and DIY projects related to portable audio, headphones, headphone amplifiers and DACs.

www.reddit.com

 

[GaryH]

We should keep in mind though that not all measured deviations and headphones have minimal-phase behaviour, which can be better seen when the excess phase group delay is generated and correcting those with an inverse IIR filter will not (fully) correct the phase.

resourcesindex/where-to-find-headphone-measurements/minimumphase-csd-ir - headphones

r/headphones: A place for discussion, news, reviews and DIY projects related to portable audio, headphones, headphone amplifiers and DACs.

www.reddit.com

As that page says though:

There are some headphones that display non-minimum phase behavior, but they are quite rare and even then are only in a small part of the frequency range.

As I said previously this headphone is a possible candidate due to the multiple swings in group delay, but yes only an excess group delay plot would confirm this. For the vast majority of headphones that are actually competently designed however, they will be minimum-phase and so a minimum-phase EQ will work to correct the phase.

 

[thewas]

As I said previously this headphone is a possible candidate due to the swings in group delay, but yes only an excess group delay plot would confirm this. For the vast majority of headphones that are actually competently designed however, they will be minimum-phase and so an IIR EQ will work to correct the phase.

Exactly, those wild swings foreshadow non-minimal phase behaviour which cannot be fully corrected by IIR EQ.

 

[GaryH]

Keep in mind that Oratory's comment was about debunking that linear phase is always better, not a firm statement that EQ don't produce artifacts.

There are no such 'artifacts' uniquely produced by EQ. It's effectively just turning the level up or down at specific frequencies. For a minimum-phase headphone, the worst this can do (just like a global volume increase) is increase distortion already present from the transducer, nothing more.

https://www.reddit.com/r/oratory1990/comments/hlt1zy/_/fx1gztn

 

[PeteL]

There are no such 'artifacts' uniquely produced by EQ. It's effectively just turning the level up or down at specific frequencies. For a minimum-phase headphone, the worst this can do (just like a global volume increase) is increase distortion already present from the transducer, nothing more.

https://www.reddit.com/r/oratory1990/comments/hlt1zy/_/fx1gztn

Sorry Gary but you are cherry picking bits of conversation, and are using it out of context. In this particular statement I took the time to underline "signal" You are talking headphones, I have already said that I understood Oratory's comment about Headphones behaving as minimum phase way and how EQ can help correcting phase response. A IIR filter is not just modulating the frequency response, it change the phase response, can we only agree on that? I's not just like turning the level a specific frequencies, You need a FIR to do that, and I do get that it's not necessary what is desirable and the phase should often be corrected as well on headphone correction. You are allowed to not willing to consider phase shift and ringing on steep filters as not being artifacts, it's just semantics at this point but a steep shelving or High Cue will add that to the signal, you would not, for example, use 9 dB Q3 at the recording stage would you? That's because it's a compromise.

 

[GaryH]

A IIR filter is not just modulating the frequency response, it change the phase response, can we only agree on that?

Yes, it will correct the phase response if the frequency response is being corrected. My comments about EQ above were assuming a minimum-phase headphone (which almost all are) and that the filters have been competently chosen, so if the frequency response is being corrected then there will be no issues with phase (in fact improvements), and high-Q positive gain filters will be avoided to prevent them self-oscillating and potentially audibly ringing.

 

[xykreinov]

Those aren't post-EQ measurements on his pdfs, they're just the stock frequency response measurement convolved with the EQ curve to predict the post-EQ response. For the majority of headphones that don't exhibit any non-minimum phase behaviour this will be an accurate prediction. From the group delay plot it looks like this headphone may not be one of them though.

Dang, really? Why did I think his were one of few that weren't convolved..
Any other reviewer I'm mixing up with? Although oratory's settiings are probably about as on the money as they can get, it would be nice to have a real world example of measurements after EQ.

 

[GaryH]

Dang, really? Why did I think his were one of few that weren't convolved..
Any other reviewer I'm mixing up with? Although oratory's settiings are probably about as on the money as they can get, it would be nice to have a real world example of measurements after EQ.

He did do it for the HD650 (along with measuring the corresponding change in distortion) at someone's request, but I think that was a one-off.

 

[xykreinov]

Might do some tests later to see how low I can get it

OML, it's insane. Right out of the box, with 12 bands of PEQ, latency is just 10ms.

10ms is pretty much low enough to not matter for me, but I figured I'd try some tweaks just for yucks. Making EasyEffects a higher priority in my task manager's CPU scheduler did nothing. Unfortunately, they haven't incorporated the fine latency adjustment settings PulseEffects had into EasyEffects, yet. So, 10ms is as low as it'll get for now.
But, to think I would have to use well over 9% CPU just to get old PulseEffects from 200ms to 70ms, and EasyEffects gets 10ms using peanuts...
Anecdotally, I can do rhythm games with no issue.
I am now convinced PipeWire is one of the greatest advents in Linux audio since ever.

 

[PeteL]

That's a problem with the headphone, not a problem with EQ.....re the distortion argument. There should be no concerns with using EQ with headphones, the only considerations are making sure distortion doesn't get out of hand which can be inferred from distortion measurments at different target dB (eg the 94 / 104 / 114dB that Amir does for instance), making sure you have enough amplification to run the headphone loud enough after applying negative preamps to cover the digital boosts, and you of course have to have an understanding of the innacuracies associated with headphone frequency response measurement the higher you go up the frequency range (as in the measurement becomes more unreliable so your EQ has to reflect that increased innacuracy by using wider filters and/or verifying by listening), but there's no problem with using EQ itself in headphones. EQ doesn't degrade quality of sound in & of itself, but it's only as good as the accuracy & relevance of it's implementation.

I never said there was a problem using EQ with headphones? I said headphones that need such drastic EQ are problematics. I repeated numerous time in this thread that I EQ is an important and necessary tool. The point I am trying to make since the start, Is that when you have to do such a boost to fix an headphone, what you enter a zone where your fix can become non transparent. There will be an overall improvement, but there will be a cost compare to having to do smaller correction on a better behave headphone to start with.

Hear me out, I'll use a different analogy. If I am doing Front of house and trying to EQ a source and I look at my board and for the instrument to sound normal I have a band at +9dB with a sharp Q. There's a problem. I stop right there, go on stage, maybe try a different mic placement, or a different mic that picks up differently, maybe there's a problem with the instrument itself, with the acoustic or with the player. Something is broken. There is a problem, if I don't find it, the EQ may make it sound just OK, but it will not make it sound great.

 

[Helicopter]

The headband looks so bad, with the cheap plasticky bits, and DIY overly supple looking grain leather. Compare this to something like Focal Clear MG, or Stellia, or Audeze LCD, or anything DCA. I ask 'What is happening with this combination of price and build / aesthetic? Jeepers creepers!' Sorry for the rant.

 

[Robbo99999]

I never said there was a problem using EQ with headphones? I said headphones that need such drastic EQ are problematics. I repeated numerous time in this thread that I EQ is an important and necessary tool. The point I am trying to make since the start, Is that when you have to do such a boost to fix an headphone, what you enter a zone where your fix can become non transparent. There will be an overall improvement, but there will be a cost compare to having to do smaller correction on a better behave headphone to start with.

Hear me out, I'll use a different analogy. If I am doing Front of house and trying to EQ a source and I look at my board and for the instrument to sound normal I have a band at +9dB with a sharp Q. There's a problem. I stop right there, go on stage, maybe try a different mic placement, or a different mic that picks up differently, maybe there's a problem with the instrument itself, with the acoustic or with the player. Something is broken. There is a problem, if I don't find it, the EQ may make it sound just OK, but it will not make it sound great.

You sounded "EQ negative" before, but you're sounding more reasonable now.

 

[Aperiodic]

So Amir... Point blank, if it came down to this or the Stealth, which would you pick and why?

 

[Skinner001]

So Amir... Point blank, if it came down to this or the Stealth, which would you pick and why?

Not sure if this is a question or a joke