The post I was waiting for. Thanks for sharing your experience man. Mine is similar, because it's about a year and a half that I own a pair of X2HR and some other headphones below 200 bucks, but it's only a week since I've finally found an EQ profile capable of making them sound warm and non fatiguing, without killing treble and details. I can share with you my EQ profile, it would be interesting to hear your take on it since I'm very proud of it hahaah.

Sure I'd be happy to take a listen. I can share mine as well but I'm not sure if it would sound right to your ears or anyone's really.

I don't know how to share a txt file so I'll just paste it I guess. Here it is:

Preamp: -8 dB

Channel: R

GraphicEQ: 20 2; 50 -2; 80 -2.2; 170 0; 220 0.8; 254 0; 267 0; 300 1.7; 360 1.9; 410 0.2; 765 2; 808 0; 833 -1; 901 0; 1159 0; 1300 -1.5; 1655 -3; 1764 -5; 2035 0; 2096 0; 2137 1; 2224 0; 2283 0; 2450 1; 2800 2.5; 3202 3; 3469 1.3; 3567 2; 3683 0; 3948 1.5; 4000 -0.8; 4100 -1.5; 4187 0; 4510 0; 4649 2.5; 4710 0; 4850 -5; 4955 -4; 5000 -5; 5158 -4.5; 5268 -7; 5352 -8; 5434 -9; 5538 -8; 5671 -8; 5906 0; 6019 3; 6189 0; 6490 -3; 7439 0; 8003 2; 8739 2; 9140 6; 9312 4; 9465 6.5; 9789 4; 10000 3; 10129 0; 10185 -1.5; 10244 0; 10423 2.5; 10581 0; 10630 0; 10696 2.4; 10763 0; 10828 -1.5; 10868 0; 10951 2; 11026 0; 11124 -10; 11266 -1.5; 11508 -6; 11585 -3; 11930 0; 12437 0.5; 13012 6; 13516 4.5; 13787 5; 14206 5; 14923 5; 15107 7; 16313 7; 17505 0

Channel: L

GraphicEQ: 20 1; 40 0; 50 -2; 81 -2; 170 0; 180 0; 250 0.5; 262 0; 275 -0.6; 292 0; 400 0.9; 433 0; 465 -0.9; 530 0; 760 1; 800 0.6; 842 0.6; 900 2; 951 0; 1019 0; 1197 1.4; 1413 0; 1650 -2.5; 1985 0; 2300 2; 2541 2; 3200 3; 4110 3; 4356 0; 4378 0; 4421 1.8; 4614 2.5; 4666 0.5; 4718 0.5; 4807 2; 4900 0; 5000 -2.5; 5096 -3; 5350 -7; 5426 -5; 5505 -4; 5590 0; 5672 -2; 5731 0; 6002 3.7; 7442 0; 7465 -0.5; 7735 0; 8288 4; 8631 2; 9005 1.5; 9424 5; 9799 0; 9890 2; 9966 0; 10060 1.3; 10097 0; 10125 -1.6; 10176 -1; 10219 -2; 10248 0; 10318 4; 10406 0; 10443 -2.5; 10506 0; 10659 -6.5; 10683 -5.5; 10732 -12; 10767 -10; 10825 -20; 10951 -5; 11092 -7; 11330 -2; 11527 0; 11645 3; 11708 0; 11776 -9; 11859 0; 11894 2; 11980 3; 12176 8; 12430 3; 12788 7; 14914 2; 15158 4.5; 15376 4.5; 15673 7; 15959 2; 16122 6; 16246 6; 16372 0; 16496 0; 16591 -4; 16739 -2; 17122 -3; 17223 -1; 17407 0; 17826 2; 17949 4; 20000 0

Keep in mind that rapid A/B switching tends to erase differences. That's a familiar problem for people who go to big meets where lots of headphones are available for demo and they try out multiple headphones/IEMs in the span of a few minutes; everything starts to sound the same because our brains don't have time to get acclimated to any one sound. It's a common phenomenon that headphones that sound good during a short demo at a show don't sound as good in the long run, because the sound qualities that make it stand out against the 5 other headphones the listener just heard make it too sharp or too unusual in a normal listening environment.

I've gotten headphones very close to one another via EQ as well (though never quite exact), and resolution is something that to me is mostly linked to FR. I actually don't like the term "resolution", and I prefer the term "tonal contrast", which I think is a more descriptive term for what I hear. Contrast is what allows me to differentiate between different sounds (similar to how visual contrast is a key part of how our eyes perform object recognition and differentiation), and to me, "resolution" is how easily I can distinguish different instruments and sounds. It's a very fine-grained balance between different frequency ranges (plus lack of cumulative distortion from the lower registers that might interfere with the presentation of the high frequencies) that produces the correct contrast for good "resolution".

Soundstage is the main thing that cannot be easily replicated via EQ, and that's because the headphone's interaction with your HRTF matters a lot for that. Even Dr. Sean Olive, possibly the foremost expert on headphone FR measurements, has said in the recent interview with Resolve and Crinacle that FR measurements aren't everything, and don't measure the spatial qualities of a headphone. I could not EQ my Sundara to have the same soundstage size as my Shangri-La Jr, even though I could approach its resolution and overall sound. But the placement of sounds is something I could not reproduce via EQ, the SGL just sounded more spacious. The physical sizes of the drivers are different between the two, so the wavefront that hits my ears is different, so the interaction of my ears to that wavefront is different as well. The X2 and the Sundara have similar sizes and shapes I recall (I only briefly owned the X2 years ago), so soundstaging differences should be less pronounced between them.

With EQ, I've noticed regions (different for each headphone) where the magnitude of EQ applied doesn't match the magnitude of the perceived change in the sound. I've noticed places where 0.5 dB makes a noticeable difference in the sound. I've also seen cases where I boost a range by 10 dB and it does nothing to erase a dip in that range (that's usually with closed-back headphones with undamped earcups). I've found that even if I can EQ headphone A to sound like headphone B, that's no guarantee that I can do the reverse, make B sound like A.

There's also another aspect of sound that can be produced with EQ, but not via standard EQs (graphic or parametric). I've started using dynamic EQ, which boosts/cuts a frequency band only when dynamic swings occur in that band, and that allows me to add the "punch and slam" of macro-dynamics into a headphone. So in a way, dynamics are FR too, but not in the FR that you can easily see in a graph, it's sort of "instantaneous FR" if you will. I've heard of "attack measurements" at SBAF and also of impulse response overshoot as metrics for dynamic performance (more overshoot in the impulse response level means more slam), but either way it's not something that you can easily see in the standard FR graph yet has quite noticeable effects on the sound.

My overall view is that I don't agree with people who say "FR is everything" and mean that you can just look at your usual FR graph and immediately know how a headphone sounds. Even experts like Dr. Olive who specialize in those FR measurements don't hold that view. I take the view of "momentary SPL at the eardrum is nearly everything". I leave open the possibility that part of what we perceive is not eardrum-related, like maybe there's an effect perceived by the skin of the inner ear canal. There's also the fact that our brain doesn't work on SPL, but on loudness, and those two do not correlate exactly.

I also like seeing CSD plots, as I've read that at higher frequencies (>2KHz and with some effect down to 500 Hz), our brain doesn't maintain phase lock with the incoming sound wave, but instead the perception process is triggered by the waveform envelope. I've heard it explained that outside of the phase-locking region, the brain "batches" sound in time, and perceives the total amount of sound occurring in each batch as its loudness. Longer sound = louder. My understanding of this is that if a peak in the FR (above 500 Hz or so) has a long trail in the CSD plot, that peak will sound louder than the plain FR would imply. You've already seen the demonstration of how EQing down a peak also cuts the CSD trail, so the headphone "double-dips" from the EQ, not only is the peak gone, but the amplifying effect of the CSD trail is also gone. I suspect that may be why I notice unusual effects when EQing, I'm changing the FR at the same frequencies where there is a significant CSD trail, so the effect is either muted or amplified. When I've done my measurements, it's usually the case that regions with odd EQ interactions also have longer trails in the CSD plot. Psychoacoustics is a really interesting field that I wish I studied more in college (I studied electrical engineering with an emphasis on computer microarchitecture, so outside of a few audio engineering classes, I never went too deep into that subject).

Damn that's a lot of stuff hahaha, what software do you use? My EQ profile is very simple in comparison.

125 Hz, -1 dB, 1.5 Q 275 Hz, -2 dB, 2 Q 800 Hz, -1 dB, 2.5 Q 1780 Hz, -3 dB, 3 Q 2250 Hz, -2 dB, 1 Q 4000 Hz, -4 dB, 6 Q 5100 Hz, -7 dB, 5 Q 7000 Hz, -5 dB, 2 Q 8250 Hz, - 0.5 dB, 6 Q (this last band is not so important)

I know it's a bit strange because there are no boosted frequencies, but here is my take: you won't need them. This headphone is already bassy, so you won't need to add any bass (maybe sub bass but idc). Mids and highs are the confused area, a lot of stupid spikes going on here. Tried oratory EQ preset but I've never found oratory presets to be the best option for my taste, and with this HP in particular, I was not very satisfied. Then tried to work by myself on A LOT of different presets, and found that adding something to this HP is not a good option at all. It only needs to be tamed.

Let me know what are your impressions. Just remember that I'm treble sensitive mostly up to 4-6 kHz and I usually like to listen with high volume (around 80 dB) .

No you didn't

If you can't hear grain on the Phillips you need to work on ur hearing

Well I never claimed to have good hearing. I just said they sound almost identical to me. Can you explain what exactly you mean by "grain"? Maybe the slight difference in separation I hear is what "grain" is.

Gritty treble and upper mids, also high thd

I use Equalizer APO. I'm used to the default interface so I never really tried Peace honestly. I listened to some stuff with your EQ profile and I measured it. It's certainly much better than default tuning. The harshness in 5-6kHz is gone, it even sounds a bit too recessed in that area for me but since you're sensitive to that I guess it's fine. I think the upper-mids are too recessed so I would recommend adding a 3000 Hz, 4 dB, 1.5 Q filter. If you don't like that you could try 2-3dBs instead for your preference.

Can you do something like this - turning Hyundais into Teslas?

Is the high THD the reason for grittiness, if not what is it? And why is it not observable in FR?

I highly recommend using the Oratory1990 Harmon eq alongside ApoEQ and Peace.

It makes the x2hrs absolutely incredible for what you pay.

Found the guy who thinks you can buy your way through the hobby.

If you read my other comment below, I said that I personally find my own preset more accurate than Oratory's one. Harman is only a target that consider what casual listeners like. It's not an absolute reference target, so Oratory presets are usually better than stock sound but it's not the Bible.

Also, I think there is nothing phenomenal about Fidelio, technically speaking. Pretty horrible tuning above 1.7k, average detail, it does not do well in busy parts. For the same price there is the HD560s or the DT880 that are more accurate and technically competent, except for soundstage that is the only thing where X2HR really stands out.

I never said it was the bible lol. Also thsts not really an accurate description of how the target was formed.

Perhaps you should read or listen to some of Sean Olives talks he describes the process quite well. Also the target is just a baseline for your finer Eq changes.

i will be more impressed if you can make a HD600 to a HD800 or even to a HE1000 v2

Hard disagree on both of those but you do you mate.

Happy to have your feedback. You're right, with that 3k boost it sounds less recessed, which is a thing I noticed but I thought that it was inevitable, having to contain the higher frequency mess. So thank you, my X2HR now sounds a little bit more correct :)

Then I want to precise that our units could be different due to unit variations, so it's all relative.

No worries, glad it helped :)

Yes, unit variation is definitely something to consider. There's even a very noticable channel imbalance on my unit for example.

Sundara now irrelevant.

I never know if people are just lying about these things, I have god-tier ears, or I am doing something incredibly wrong when eqing headphones to match each other. To me the differences are night and day. If I EQ my HD 600 and AKG k612 to the same FR, I can clearly tell the superier soundstage and imaging of the AKG and the resoultion and timbre of the Sennheiser apart. Even when I EQed my DT990 and 880 to match each other I could clearly tell them apart in a blind test. With Amps it gets very difficult to tell them apart while switching between them, but I am imagining differences in longer sessions. I might be hallucinating on that one, or it's true that everything sounds similir when switching quickly between things.

Are you using in-ear mics to measure as well?

Yes, you're doing things wrong when matching headphones. To properly equalize 612 and hd600 for example you have to take into account that these have a completely different upper treble presentation with different placement of upper treble peaks and it can drastically impact this "resolution" and "soundstage" etc etc. You really have to do this the way OP did, using microphones and measurements to precisely match every single part of the FR or at least bring them as close as possible and even then there's no guarantee that you're gonna have a same FR for both at the eardrum.

not true

Thank you very much for sharing your knowledge. I can't say I am qualified to fully understand everything you said (and it's even harder to do so because English isn't my first language) so I have a few questions if you don't mind.

What exactly is "cumulative distortion from the lower registers"? That and FR are the only 2 things that determine a headphones' resolution/tonal contrast then, correct?

I always thought that angled/far drivers or different sized drivers have different soundstages because pinna changes the FR of the sound that is entering ear canals differently. Therefore spaciousness and directionality of the sound is mostly (maybe even entirely) determined by pinna and since in-ear mics roughly measure the sound arriving my ear canal entrance (so it takes the interaction between the headphones and my HRTF including my pinna into account), can we really not replicate soundstage using EQ? If we can fully match the 2 sounds entering my ear canal, my eardrum should hear identical sounds as ear canal will react identically to both sounds, should it not?

If I understand correctly overshoot in impulse response level is slam. So if an impulse of larger than intended amplitude is created it will have more slam and maybe will sound nicer but is it the intended sound? I'm not asking if it's intended by the music producer, I'm asking if it's closer and more accurate to the digital input.

I've heard from multiple people that most headphones are "minimum phase". I don't know what exaclty "minimum phase" is but what I understood from it is that in CSD plots, if there's a peak in FR there will be a peak in decay time and vice versa and they match well enough so that it is under audibility threshold so they don't matter. Is this correct?

I now strongly agree on the idea that "momentary SPL at the eardrum is nearly everything" as FRs don't show how the headphones react when more than one particular frequency is played.

So if a headphone can't keep up when multiple instruments intended to sound like they're coming from different directions are played, I think the sounds might bleed into each other and hurt the fine details of the sounds and the sense of directionality. Could this be what people refer to when they use the terms "separation, resolution, imaging"? And I have a feeling this is related to the attack and decay speed of the headphones, is this true?

This. The only two notable imperfections about this method are these two initial assumptions:
1- If two identical sounds enter the ear canals, they will sound identical to the ear drums.
2- When more than one particular frequency is played, how the headphones react to the input will not deviate from their FR.

cope

When I mentioned cumulative distortion, I'm referring to how the energy present at a specific frequency in a multi-band signal is comprised not just the energy in the signal itself, but of it summed with all of the distortion products of lower tones. For example, the amplitude at 2 KHz is not just the 2 KHz component in the signal, but also includes energy from the 2nd harmonic distortion of the 1 KHz component, the 3rd harmonic of the 666.66 Hz component, the 4th harmonic of the 500 Hz component, etc. That's what I meant by cumulative: the level at each frequency depends not just on what's in the signal, but on the distortion components of lower frequencies that are played at the same time which lie at the same frequency.

In theory, if you could exactly match the waveform seen at the eardrum, then yes, you would hear exactly the same soundstage and imaging. However, I have never been able to properly do this in practice with over-ear headphones. Additionally, I've heard from an acoustic engineer that soundstage is partially influenced by physical factors; if the headphone is touching your ears, it hurts the illusion of soundstage because your brain knows that the sound is coming from right outside of your ear. In general, the brain prioritizes non-auditory inputs. That's why the McGurk Effect exists: when there's a conflict between what your eyes see and your ears hear, you literally hear what your eyes see, even if the actual auditory input doesn't match.

Regarding overshoot, in theory, less overshoot means it's more accurate to the input signal. That's what Dan Clark says to justify the macrodynamic performance of his headphones; he says that other headphones overshoot in their impulse responses, but his headphones do not. Many people think his headphones sound really dead and lifeless as a result, but that's where science meets art. If the music was produced on gear that has more overshoot, it probably has lower dynamic swings in the signal. Should the headphone reproduce the signal as is, or should it try to reproduce the dynamics that were in the original performance, but weren't mastered into the signal? There's no single right answer to that question, it's a matter of design philosophy and preference.

Regarding minimum-phase, it means that the phase response is exactly the amount needed to produce the frequency response. There's no excess group delay across the entire frequency range. In theory, the CSD plot shows nothing that isn't already in the FR, and generally weirdness in the CSD plot is reflected in peaks and troughs in the FR graph too. I used to hold strongly to that view, but now I'm not as certain that CSD plots have no value. All physical devices have resonances, and at higher amplitudes, those resonances are the first to exhibit serious non-linearities. In general, if I see a long trail in a CSD plot, then I take it as a sign that I should be very careful about boosting that region in EQ. If I cut, that's fine, because the trail disappears with the cut, but if I boost, then that trail will become more significant, maybe enough to become audible at high volumes. There is one case, the Koss KSC75, where I actually hear something like ringing in the lower treble (it sounds like a bit of microphone feedback when certain notes play), which is probably a resonance, but it goes away when I EQ down the 5 KHz region.

On the more practical side, I can only presume that phase is an issue at the design level. Many companies have tech in their headphones to control phase effects. Phase effects tend to result in weird, narrow peaks and dips in the FR. Those features become difficult to EQ out, and if you look at Oratory1990's EQ presets, he often doesn't fix those really narrow irregularities because they stem from phase effects that will sound really strange if filled in via EQ.

For your last question, speed isn't a real metric in headphones as far as we can tell. Some headphones certainly sound like they attack/decay faster or slower than others, but there's no concrete metric that can be exclusively tied to that phenomenon. Here's an article by Brent Butterworth at SoundstageSolo! that showed a perceptively slower headphone actually responding faster to the input than a fast-sounding headphone. Given my experience with dynamic EQ allowing me to add macro-dynamic punch to a headphone by overdriving large transients, I suspect that separation is part of "micro-dynamics" where small transients are being overdriven by a headphone. But there is no scientifically backed measurement that explains the perception of attack/decay speed in headphones.

I will check it out, thanks. I wasn't claiming that you consider it as the bible, mine was just a consideraton. I agree on your definition.

But recently I did a test with all my HPs. For each one, I compared (obv with matched pre-gain volumes) the Oratory preset with another Oratory preset but with some modificaton based on my tastes and with a third preset, built looking to compensated FR graphs and simply correcting manually all spikes and dips. The results shows that Oratory preset were never pleasing and accurate as mine. Did the test also with a friend that is a sound engineer and House music producer (more trained ears than mine) and while he retains that Oratory presets are more balanced than stock sound, he also finds that my personal presets sound more linear and accurate. With oratory presets I usually perceive too much bass, voices are laid back and highs are a little bit "muted".

I am not using any mics. I am using measurements and my ears. But the differences are so big that I can't imagine they can be up to 1db more or less here or there. Just as an obvious example the bass of an HD 600 sounds completely different than that of a Sundara when both are equed to flat. The HD 600 sounds like it is struggling and a large part of the resolution in the mids/treble is lost. Or I'm sure you'd agree as well, that an open and closed headphone sound different, even when they have the same FR. Or even more extreme, an IEM and an open headphone are going to sound completely different, even if you manage to match FR.

Which software did you use to render the output of the microphone into a frequency response?

Well, if you're not using any mics you're not really matching their FR. Your HRTF interacts with different headphones differently and there's unit variation. Measurement graphs online don't tell you how your ears hear a headphone.

I used Room EQ Wizard.

I don't feel like you engaged any of my arguments. Do you think an open headphone and an IEM are going to sound the same if you managed to match FR?

If the EQ profile to match them didn't introduce any audible distortion then they should sound almost identical. I would even argue you could make a headphone sound almost exactly like a speaker. I heard SMYTH Realiser A16 does just that very well.

Having said that, your perception of the sound might change when using an open-back headphone since you can hear ambient sounds in the room. However if you were in a completely silent room which is pretty much impossible to achieve, you should percieve them identically as well.

I feel like your understanding of how we perceive sound is wrong, but I have neither the knowledge nor time necessary to argue with you. All I can tell you is that a speaker and IEM with matched frequency response sound completely different. I'm sure you'd agree that I'd be able to accurately tell you for any item I have never heard if it is a speaker, headphone or IEM, no matter how you EQ it as well. I see sound in shapes and colours and it is just completely different things.