[pinnahertz]

Establishing theoretically "correct" headphone EQ is tricky, but there are some experts who have done it and done it right.  Has anyone tried Audyssey AMP?  If you know about Audyssey from the room-EQ world, same people, applying the same measurement technology to headphones. However, there are two primary hurdles they've had to overcome.  One is a method of coupling headphones and earphones to a measurement mic.  It takes a simulated ear that you can seal over-ear headphones around, let on-ear headphones sit on top of, and fit in-ear earphones and sealing IEMs into.  If you don't have something like that, taking measurements doesn't get you very far.  
 
Next, they researched what the target curve should be for each type of headphone/earphone, and from what I gather, it turned out different for each type.  Finally, they take specific headphones and profile them, using the Audyssey measurement software, and develop a "tuning" that you load into the app to try for free, then buy for a couple $ if you like it.  
 
To that they apply the headphone version of Audyssey Dynamic EQ, which compensates response dynamically for different overall play levels.  It's like really smart FM curve...only changing as needed.  
 
So, here's my idea: get the app (free, IOS only, sorry), get your headphone tuning loaded, audition it.  The ones I have are all superb, BTW,  fixing all my complaints across my 3 favorite headphones/earphones.  Yes, different tunings for each, you select when you plug in new ones and the IOS device detects that, pops a menu.  
 
Anyway, load your tuning.  Now, using REW or another response measurement system, measure the resulting response electrically at the output jack of the player.  Play a pink noise file, or sweep file, at different volume settings.  The one at your typical listening level would be the approximate curve you would want to dial into your favorite EQ.  And, at low levels, you'll partially see the action of Dynamic EQ.  You won't be able to duplicate the change, and the specific LF boost you see with pink noise or a flat sweep won't be quite right, but mid band and up, it should be dead-nuts-on. 
 
What this would do is effectively mootch Audyssey's precision measurement from their artificial ear and software, and resulting tuning, and let you set it into a fixed EQ of really any player, any platform.  It'll cost a couple of bucks for each headphone you do, but that's way cheaper than buying an artificial ear or head for your one measurements, and most importantly, you'll have their extremely well researched target curve built in there too.  
 
How's that for a "cheat"?    I have not tried this yet, need a bit of free time.  If I get to it I'll post results, but I'll be one of you guys beats me to it.
 
Heck, someone could even build a database of the resulting curves. 

 

[Joe Bloggs]

It's been a while since I viewed this thread. I have since changed what I do to try to get the sound to be flat. What I do now is closer to what I believe castleofargh tried to say in his response to my first post, where I trust my ears more than a graph, since graphs can have varying results. I now use a test tone sweep file at or close to the loudest commonly used volume I can tolerate to check for a flat signal. After days of equalizing to adapt to my changing ears (and *maybe* the headphones too, though I have my doubts), The changes I made to the frequencies, as of now, are significantly less dramatic than they were when I was using an inverted graph.

Also, whether or not EQing headphones is a bad idea or not doesn't need to be said here. Yes, you can equalize on the fly, say, on your phone, but the way I do it in this situation, It is a bad idea. It's terribly impractical to have to render every song I want to listen to with these equalizer settings applied in a DAW based on my hearing which is constantly changing. Not to mention that every time I make a change to the equalizer I have to re-render every song one by one from the beginning. Of course it's a bad idea to do what I do. It's practicality isn't even the point. The point of this, the reason I am doing this at all is it is very thrilling for me to know that I can make a terrible headphone sound better than almost any other headphone I have heard, excluding every factor that goes into headphones other than simply the flatness of the frequency spectrum.

You mentioned adding a Fletcher-Munson curve EQ to your chain once. I also do this to compensate for my hearing, but the important point to avoiding a zero-sum game is to apply the F-M curve EQ ONLY when tone-sweep testing, you pull out the F-M curve when you've finished the testing and start listening to music.

The point of adding the F-M curve is to compensate for the fact that, listening to a pair of well-tuned speakers or headphones, you wouldn't perceive all tones at different frequencies to be of the same loudness.

Here's my messy thread on the topic: http://www.head-fi.org/t/615417/how-to-equalize-your-headphones-advanced-tutorial-in-progress

As for your statement on practicality: you'd be surprised. If you have a rooted Android you can install Onkyo HF Player and create an EQ preset, then pull out its corresponding xml file from the app's data path and find that you can pretty much edit and save a long list of control points in much the same way you do on ReaEQ--so you would just need to consolidate your settings into one EQ instance and copy the control points to the xml file.

As long as you've already rooted your Android, you may as well try installing Viper4Android too--that lets you export your cumulative EQ settings--including different settings for left and right channels--simply by running your plugins through a Dirac impulse. Save the result as a wave file, put it in Viper4Android's relevant directory and have it load the file as an impulse response, and if all goes well, it will process all Android system audio, meaning both locally stored music and most streaming music can be processed.

 

[castleofargh]

You mentioned adding a Fletcher-Munson curve EQ to your chain once. I also do this to compensate for my hearing, but the important point to avoiding a zero-sum game is to apply the F-M curve EQ ONLY when tone-sweep testing, you pull out the F-M curve when you've finished the testing and start listening to music.

The point of adding the F-M curve is to compensate for the fact that, listening to a pair of well-tuned speakers or headphones, you wouldn't perceive all tones at different frequencies to be of the same loudness.

Here's my messy thread on the topic: http://www.head-fi.org/t/615417/how-to-equalize-your-headphones-advanced-tutorial-in-progress

As for your statement on practicality: you'd be surprised. If you have a rooted Android you can install Onkyo HF Player and create an EQ preset, then pull out its corresponding xml file from the app's data path and find that you can pretty much edit and save a long list of control points in much the same way you do on ReaEQ--so you would just need to consolidate your settings into one EQ instance and copy the control points to the xml file.

As long as you've already rooted your Android, you may as well try installing Viper4Android too--that lets you export your cumulative EQ settings--including different settings for left and right channels--simply by running your plugins through a Dirac impulse. Save the result as a wave file, put it in Viper4Android's relevant directory and have it load the file as an impulse response, and if all goes well, it will process all Android system audio, meaning both locally stored music and most streaming music can be processed.

I'll need to bother you about impulse responses some day(or really go and test a lot of things myself). the only way I know to get an impulse is through room EQ wizard. but then I have no idea what I'm doing with the settings options before exporting to wav for viper4android. I end up with stuff that seem to work(as in if I remove bass I get less bass with the convolved file in viper), but I would need to spend some real time recording the output with all sorts of settings to see what's what, if normalizing does something, if I need stereo(don't see why unless I use left/right EQ but I haven't even tested that). and if I can cut some or change the amplitude in audacity etc etc. I tried this out of nowhere, got it to work kind of fine by pure luck, in a fully digital loop with VAC, after being frustrated that I couldn't use as good an EQ on my tablet as I do on the computer. I usually convert music with the EQ for a given IEM, but that time I felt adventurous ^_^.
anyway I never got into it to learn the proper way and how it really works because I don't know where to find information about it. all I've seen are people using convolution to capture room sound, but they always have some fancy software. I plan to stay cheap and as low fi as possible ^_^.

 

[Audman71]

You mentioned adding a Fletcher-Munson curve EQ to your chain once. I also do this to compensate for my hearing, but the important point to avoiding a zero-sum game is to apply the F-M curve EQ ONLY when tone-sweep testing, you pull out the F-M curve when you've finished the testing and start listening to music.

The point of adding the F-M curve is to compensate for the fact that, listening to a pair of well-tuned speakers or headphones, you wouldn't perceive all tones at different frequencies to be of the same loudness.

Here's my messy thread on the topic: http://www.head-fi.org/t/615417/how-to-equalize-your-headphones-advanced-tutorial-in-progress

As for your statement on practicality: you'd be surprised. If you have a rooted Android you can install Onkyo HF Player and create an EQ preset, then pull out its corresponding xml file from the app's data path and find that you can pretty much edit and save a long list of control points in much the same way you do on ReaEQ--so you would just need to consolidate your settings into one EQ instance and copy the control points to the xml file.

As long as you've already rooted your Android, you may as well try installing Viper4Android too--that lets you export your cumulative EQ settings--including different settings for left and right channels--simply by running your plugins through a Dirac impulse. Save the result as a wave file, put it in Viper4Android's relevant directory and have it load the file as an impulse response, and if all goes well, it will process all Android system audio, meaning both locally stored music and most streaming music can be processed. 

Thank you for the tutorial. I will look at it when I have a chance. I don't add the FM curve or any kind of curve in my EQ settings anymore. My judgements of loudness can change. Right now I'm judging how loud a frequency is by how it feels in my head, just loud enough to not hurt my ears, rather than how loud I can hear the frequency. They seem to go hand in hand, and it is working pretty well, except I have to keep it pretty quiet so the cymbals or other treble instruments don't hurt or damage my ears.
 
I switched to IOS a few years back, and it's times like this where I wish I never did 

. When I can equalize everything out of my iPhone as accurately as a surgeon, I will be happy.  
 
 
By the way, castleofargh, from way back when:
 

little advice though, you should not try to compensate the roll off at both ends of the frequency response like you did. if the IEM rolls off in the bass and trebles, it's most likely because of physical difficulty. by pushing harder on those difficult frequencies, you're most likely creating a lot of distortions without really bringing the sound where you expect it to go. for the bass I would stop trying to rise at where the 50khz is. but that's just me. and same for trebles.

 
If I can hear and\or feel below 50 hz or above, say, 16000, why wouldn't I raise the parts where the headphone rolls off so I can hear the frequencies I naturally hear better? I don't care that much about the technical aspects if I can't hear them, and I can't hear very much, if any, distortion that isn't already part of a song to begin with (For example, when listening to hard rock type music through my settings)

 

[castleofargh]

that's a very general advice, like anything else, how "wrong" it is will depend on the headphone, the amp, and the magnitude of the boost. if you feel like you get a result that pleases you, go ahead.
at a very basic level when everything is fine, you double the voltage at a frequency and you get 6db louder. as long as the driver can do this, using an EQ is a great clean tool. but any driver will reach a point where it will physically be unable to follow the signal and reach the desired amplitude. pushing over that will only create massive distortions.
 
the other point is that some roll off can be huge, and adding a 20db boost on the digital side of things may require to lower the gain by that much to avoid clipping(depending on the music and the frequency boosted). then you will compensate with the amp to still end up with the same listening level. at this point comes the question, is my amp able to provide the old listening level+20db?  totally made up example, I was listening to music on my headphone at 0.8V, something almost any source can do.  after my +20db boost to get the trebles up, I may now need up to 8V to get the same loudness as before. my amp doesn't do 8V into the load of my headphone and will start having massive distortions after 7V.   that obviously an extreme case, but it's one of the things that one may have to care about.
 
my advice about roll off on both ends includes this. because if you need to boost more than 10db in the midrange, you've most likely just bought the wrong headphone ^_^.