"A picture tells a thousand words" is a common saying, but it doesn't seem to apply to headphone audio. Certainly not if you're talking about frequency response graphs as nobody deems them nearly as useful as a worded review on how the phones actually sound.
Nevertheless, I am curious as to how many words a graph can tell if used to its full extent. I have been compiling a list of filters that apply EQ according to an approximate inverse of the EQ graphs found on select measurement sites that have diffuse-field compensated measurements (such that an EQed to flat sound according to such graphs should have a close to reference frequency response)
These EQs are applied using a parametric EQ with up to 24 bands (which can apply more accurate corrections than even a graphic EQ with 31 bands)
There are 3 types of files available here:
1. Graphs: these show the curve of the EQ that is applied in (2) and (3).
2. Electri-Q .e-q files: these can be loaded with the free parametric EQ program Electri-Q (posihfopit edition)
The link provides a VST plugin, which may be loaded with e.g. foobar2000
A winamp plugin is also available in the same install.
3. Impulse response files: these are the same EQ recorded as a 16384-sample impulse response. These can be used in an impulse convolver (again, such as available on foobar2000). Notably however, Viper4Android is a program for android phones that can also load these impulse responses:
Currently included earphone models in alphabetical order (will be updated regularly)
Beats by Dr. Dre Mixr
Beyerdynamic DT990 Pro 250Ohm
Etymotic ER-4P (medium insertion depth--not-quite-deep insertion)
Sony MDR-1RNC (noise cancellation mode on)
Sony XB90EX (with two presets, "bassy" has a subbass boost (relative to reference) while "maxxbass" has both subbass and midbass boost (relative to reference)
Ultimate Ears TF10
Ultimate Ears UE100
Ultimate Ears UE200
Ultimate Ears UE900
Latest addition: Sennheiser CX300-II (19 Oct)
You may leave requests for your model of earphones to be added to the collection Please check for the availability of frequency response curves on at least one of the following websites:
When requesting, please leave some comment on your opinion of the stock sound of the earphones without effects running, so I can fine tune the EQ/IRS to your taste. (the EQ/IRS will always adjust towards reference sound so is suitable for everyone with the model of earphone but will be a bit fine tuned to the taste of the one who first requests them) Opinions on the frequency balance (e.g. too midbassy? Too cold (sucked out lower mids) / warm (opposite)? Treble too sharp?) will be particularly helpful.
Finally, a link to the original XDA-developers thread, with users' positive feedback on the headphone optimization filters
Edited by Joe Bloggs - 10/18/13 at 9:09pm