Here are the first initial and easiest HEK mods, I call, the rear strips (sissy) mods. For the HiFiMan HE 1000.. What this mod does: 1-Wake up its laid back midrange... 2-Elevated its foggy micro detailing from obscurity. 3-Give it's trebles more presence.. 4-Realize & retrieve it's layered soundstage from the current ghostly imaging. 5-Revive some hidden potential, like was done to the HD800. This will be a reversable mod, With 4 levels of choices, but is a starting example for you to try . OK so onto the mod... It needs to be critically placed at the key locations I will post in pic, to avoid tonality or soundstage issues. So this is done by adding a small strip of damping material in two key locations of the rear of each cup. You will need two strips per side, For a total of four strips, long enough to reach end to end. Here is a pic in bright colors for examples. *Pic* Look ma, orange peels! Just kiddn, it's creatology foam in orange for illustration purposes. Reminder, these two strips need be in these exact locations to avoid any tonality issues. *Pic* Here is is with felt, my 1st choice of material. This mod is deceivingly simple, Yet critically placed for preserving tonality & soundstage. OK, so now onto the four choices of materials: *pic* I have numbered them to note both material and sonic preferences: 1- my first choice, a single layer felt strip. A detailed, lively and spacious presentation. 2- dual felt strip, for some treble attenuation to make more neutral on brighter units without any other loss. 3- felt with creatology on top. softens trebles further and also softens upper mids. Maybe most neutral but midrange is not as lively on some units. 4- single creatology strip. My first mod giving a liquid smooth tonality and most treble attenuation, but midrange presentation is more intimate than others with a bit less percieved bass. These are the first initial easy mods and can be combined various materials. The only "rule" is to place them on the exact row pictured. Enjoy!