How to properly equalize headphones?

Question

I have a pair of headphones - it doesn't matter which exactly. I read some overviews and technical reviews and find out that some frequencies are "unbalanced", like the middle range may sound more quiet than it should, or too loud basses, etc.

I assume that for at least each headphone model some technical guy may create a sound profile, which may be directly applied to system-wide equalizer, so that I will listen to the music compositions in a way that they should sound.

Are there any means to acquire such profiles from anywhere?

Example: https://www.rtings.com/headphones/reviews/audio-technica/ath-anc9

Answer 1

I usually use pink noise and adjust band per band, counter-equalizing the device I'm calibrating for. I listen to the noise while moving each band up and down, untill I feel like it's balanced. Then I apply this correcting equalization when I mix/listen to music.

I also don't believe in burn-in, it has been proven a myth

Answer 2

You already have some nice answers here and there, but I'll also post mine here.

UPDATE: For more information you can have a look here.

Mark is right in the fact that the brain can adapt (for more information see this and this publications). But in my opinion this is not directly connected to the question here. I do believe that you should try to "correct" the frequency (and time) characteristics of your headphones for "optimal" reproduction.

Without going into much details here, one way to "cancel" the effect your headphones "impose" to the signal, is to calculate the inverse filter for your headphones. This is not always easy and even more, not always the optimal solution. It can introduce time smearing, excess ringing and even non-flat frequency response if not done correctly.

One simple way is to try to invert the frequency response of your headphones like Tetsujin proposed in his comment. Although, as already mentioned do that with increased caution, as it may result in unwanted artifacts making the result worse than the original version.

I don't really support the idea of using graphical equalizers for such processes (like Polyterative suggest..., I believe), as most of the time their centre frequencies and Q factors (bandwidths) don't give enough flexibility to work with (most of the time you will end up treating frequencies that you don't have to). They may end up providing an improvement though, if you are lucky enough (so that centre frequencies and bandwidths come close to the "problematic" regions of your frequency response).

Ideally you would measure the response of your headphones with some miniature microphones at the entrance of your ear canal and then try to invert that. This has of course some complications starting with "how am I supposed to measure that?" and going as far as to "what is the inverse of the response?".

If you have a measurement laboratory close to you, or an audiologist has appropriate equipment, and you are willing to go into the process, you could measure your headphones there. There are also implications here as you should somehow also take care of the blocked ear canal induced alterations but this is kinda minor compared to the "imperfections" of the transducers I believe.

Regarding the inversion, it is a process that needs some technical expertise, which involves filter design and calculating inverse filters. You could achieve that with tools like MATLAB and its Signal Processing Toolbox or its free and open-source counterpart Octave and Signal Package. Otherwise, if you want something less technical, you could possibly use any frequency analyzer that would give you both magnitude and phase.

Finally, possibly the best (and safest?) solution would be to get in contact with the manufacturer and ask for the inverse filter, or just the frequency response (or its inverse) and use that.

Answer 3

I found the project that does exactly what I wanted: https://github.com/jaakkopasanen/AutoEq

They provide the WAV files for convolution equalizers, filters for fixed band and parametric equalizers too.

Also their headphones' database is huge!

I.e. the pulse-effects software on Linux directly supports WAV files via the Convolver.

Answer 4

That's generally not how things work. Headphones are like an extension of your ears. Your brain is always adapting the information that it receives from your ears in order to allow you to perceive a particular spectral response. If you have a particular reference recording you know well, just spend time listening to this recording through the headphones and your brain will quickly adapt to the new spectral response from the headphones.

If you are finding this process tiresome or stressful, then you probably are listening through headphones with particularly pronounced spectral peaks. This is why some headphones are easier to listen to than others. Some headphones preference the dialogue range particularly.

It is not necessary to listen to output material through an equalizer as your brain will be immediately 'equalizing' the sound upon reception. Just Listen.

Here's an example to show this in action. Take wideband pink noise and then apply a notch filter at around 1 kHz. Listen to this in your headphones for about a minute. Then immediately switch to flat full band pink noise. You will be surprised to hear a distinct tone at 1 kHz.

Answer 5

I've heard that playing white noise through them for extended periods of time will help "break them in," given that white noise encompasses every frequency across the spectrum. Worth a shot.