In audiophile circles, equalizers are prescribed only as a last resort to correct imbalances in recordings and room acoustics for loudspeaker playback.
http://headwize.com/projects/showfile.php?file=equal_prj.htm
In my quest for the perfect headphones, I searched far and wide to hear every pair of headphones that I could get my hands on. I heard the Stax electrostatic headphones.
http://headwize.com/projects/showfile.php?file=beyer_prj.htm
I first thought electrostatic headphones were a joke. It didn't sound safe to strap high voltage transducers to your head. But after my work with electrostatic loudspeakers, I had the skill and knowledge to try building a pair and listening to them.
http://headwize.com/projects/showfile.php?file=radford1_prj.htm
Check your phones for continuity. Most high impedance phones are about 1000 ohms per phone. Since the phones are connected in series the resistance measured from wire to wire of the phone cord and should be around 2000 ohms.
http://headwize.com/projects/showfile.php?file=provost_prj.htm
This article has two parts. Part I describes a way to determine the effective average impedance of a pair of mono headphones or a speaker using a device called a FILVORA. Part II shows how to compare the sensitivity of two speakers or two mono headphones using a dual FILVORA, even if the headphones differ greatly in impedance.
http://headwize.com/projects/showfile.php?file=tongue1_prj.htm
In my quest to understand headphone design, I have modified several models. I never changed or touched the transducers, but all the parts around the transducers were fair game.
http://headwize.com/projects/showfile.php?file=mill1_prj.htm
Electrostatic headphones continue to capture the imaginations of audiophiles, although dynamic types comprise by far the largest portion of headphones sold.
http://headwize.com/projects/showfile.php?file=cmoy3_prj.htm
Try this project with a pair of inexpensive or disposable headphones first. Otherwise, purchase one or two additional sets of ear cushions for experimenting, so that the headphones can be restored to original condition if desired.
http://headwize.com/projects/showfile.php?file=connors_prj.htm
The original modification for the Koss Plugs was a substitution of the cushions only. This revision describes a second modification to mitigate the "tinny" sound quality that manifests itself even after the cushions are replaced.
http://headwize.com/projects/showfile.php?file=cmoy4_prj.htm
This collection of Grado headphone modifications comes from posts by Skippy, Beagle, TimD, Voyager, Neruda, Chych and Squirt in the HeadWize forums and from Kevin Gilmore's Pure Class A Dynamic Headphone Amplifier project.
http://headwize.com/projects/showfile.php?file=grado_prj.htm