That’s quite a stretch. You can use an equalizer to improve the sound of a headphone but there are literal physical limitations to it. Not all drivers are equal in size or speed. Not to mention that there’s a difference in the size of their enclosures as well as the technology they use (electrostatic, planar or dynamic for example). There are lots of sound characteristics that will never change regardless of how much eq you use.
So no, a $50 dynamic headphone will not sound as good as a planar magnetic $500 one. If you think otherwise, please provide a source or at least an example.
The thing is, distortion (maybe more accurately called nonlinearity) is the only known objective way to measure the difference in sound quality between two headphones EQ’d to the same target. (there are some other measures like signal-to-noise ratio but they are even more useless) And the difference in the value becomes very small for a technically good $50 headphone and the best headphone ever made. (technically good eg. the natural frequency response isn’t crazy far from your target and the nonlinearities are competitively low)
Now, two headphones EQ’d to the same target, even if both are measured to result in the exact same sound, won’t actually sound the same to your ears because the “head dummy” used for the test doesn’t have the same ear shape and characteristics as you do. But unless there is some strong evidence that the headphone manufacturer has a better methodology than what is publicly available, then there’s no reason to think they are somehow able to account for your specific ear’s needs without custom designing the product just for you. - You’re left with having to either EQ yourself, or using dozens of headphones and testing which you like the most. And the EQ route is going to be much faster and cheaper
for sources, these discussion seem the most useful
https://www.reddit.com/r/headphones/comments/144yaiq/why_dont_we_measure_headphone_resolution/jni4z70/?context=5 (whole thread is useful)
you can say that most people who spend a lot of time and money trying to achieve “perfect audio” seem to think that EQ is only a supplement to already good headphones, but given that there has been no success at objective measurements of quality and that many people swear the thousands they spent on insulated golden cables improve their audio quality, I err on the side of saving my money.
My man, do you have ears? Have you personally confirmed your theory? Because I (sort of) did. I’ve used earpods, earbuds (cheap sennheiser models like mx365 and mx200 and akg k312p), various headphones (AKG k44, k361, k712 pro, ath-m40x, sennheiser hd518 and hifiman edition xs). I’ve also always used eq when I can. Usually the ones from Oratory1990.
There are tangible and considerable differences between all of those headphones/iems. For example, no amount of eq is going to make a 5mm driver sound like a 50mm one. On top of that, the tonality characteristics of the driver can’t be perfectly equalized to make all headphones sound the same. Soundstage is also not something you can eq for. No amount of EQ would make an Audio Technica ATH-M20X sound like a Sony MDR Z1R.
Additionally, have you considered usability? Not all platforms have a way to eq your headphones easily. Even if you can do it, it’s not something integrated to the OS, most people don’t even know what a low-pass filter and they do not know how to set it up. In other cases, such as android, you can use eq in your music player (I use poweramp for this) but it’s not a system-wide eq. If one headphone is significantly better than another one out of the box then yeah, that has value.
So again, I ask, do you have any real-world examples for this theory of yours?
“tonality characteristics” and “soundstage” are subjective words that have no concrete definition. Other similar words are “grain”, “speed”, “separation”, “resolution”. They can’t be objectively measured, and are most likely just another function of frequency response.
The differences between headphones are most likely your ear having a different shape from the reference ear used to make the eq targets, leading to a different final perceived frequency response. (or limitations in the accuracy of the measurements, most targets I believe are “smoothed”)
I’m going to trust the (claimed, who knows, maybe oratory1990 is a liar) consensus of audio engineers over your anecdotes. As I said there are plenty of audiophiles whose “lived experience” is that $2000 golden cables are necessary and that they can tell the difference between any $200 and $1000 DAC (even though a decent DAC in that price range already has a dynamic range and signal-to-noise ratio of 100-120dB which should be totally indistinguishable from perfectly clear audio for all humans
personally the only decent-ish headphones I have are DT 880 600 ohm and a JBL 760NC. The latter kind of fills all the boxes of being a wireless headphone and has poor reviews and a poor default sound profile. But after EQing both, I can’t really notice any difference except when very carefully doing side-to-side comparisons (besides the much better comfort of around-ears vs over-ear).
In contrast I believe I can tell, with some songs, the difference between 320kbps mp3 and flac (just 44.1khz), but even there I’m not sure it’s not just placebo
Usability is kind of secondary, android should have jamesDSP and the venn diagram of people that know the best headphones to buy (instead of beats by dre) and who can setup an EQ (install an app and follow written instructions) should have a lot of overlap
I will say though that more expensive headphones are probably going to last longer and are probably much more comfortable
