Hifiman HE500 & HE400 Jergpad Mod v2.0
(Feb 28, 2013)
PREFACE
This version 2 of the Jergpad mod is an evolution upon the first version, as I collected more ideas for modifications, and consolidated old methods to optimize the protocol. The essential goal of this series of modifications is to optimize the sound conducting from the Hifiman drivers to your ears, through tweaks and changes on the Hifiman stock pleather earpads.
Instead of the scatter-brained babble with confusing instructions that was the first version of this mod, I am able to organize my thoughts and split the mod into 4 components here.
- The ‘core’ damping holes mod
- The backvents minimod
- The velour-top mod
- The sub-bass adhesion mod
The first 2 mod components are directly inherited from the first version of Jergpad, but I have refined the methods so that they are 1) less destructive on the earpads being modded, and 2) much, much simpler to understand and carry out (hopefully).
The second 2 mod components have interesting stories.
The velour-top mod came about as I was reading Mad Lust Envy’s complaints about his hate for leather/pleather earpads, and another user harked back to the special earpads that Sennheiser Orpehus used, which had a velour top on a leather base earpad; later another user Beaver316 carried out a similar mod, sewing a piece of felt cut-out onto his pleathers to great effect. Having little to no sewing skills, I had to find an alternative way, and thus this was conceived, and to great effect! This medium-difficulty mod transforms the sound by opening up the imaging and giving the overall sound signature an "out of the head" sense, via the unique ability of the velour to break the seal of the pleathers without negatively impacting the innate tonal balance.
The sub-bass adhesion mod was something I always wanted to try out even before Jergpad v1.0. I always knew that Audeze LCD2/3 earpads were installed by adhering the pads onto the cups with double-sided tape that they provided (video: http://audeze.com/padschange, scroll to the bottom for the video), and the consensus has been that it allowed for optimal bass conduction. I never did it before as it is a semi-permanent change that is a mess to clean up. Eventually trying it though, revealed that it indeed granted a dramatic boost to sub-bass conduction; my HE500s now extend comfortably down to 20Hz (it previously rolled off quite hard by 25 Hz). The fact that it is a semi-permanent mod means it is the last on the list, so that you can choose to do it, or not. I would recommend that you go the extra mile and do it though.
P.S. Other Hifiman ortho owners (e.g. of HE5LE/HE4/HE6) are also welcome to try Jergpad mod. I could only test it on HE400 and HE500 but it would make sense that the improvements are less about synergy, and more about intrinsic improvements to the sonic qualities of the earpads.
Now let’s get to it…
TOOLS NEEDED
1. Pic of all the tools needed assembled together
- A pair of Hifiman stock pleather pads, with the mounting rings
- A pair of sharp scissors, or xacto knife (any precision cutting tool you are comfortable with)
- A Sharpie marker
- Electrical tape, or duct tape (any kind of thick rubbery tape really)
- (For Parts III & IV) double-sided adhesive tape (thin variety, where the adhesive tape is extremely thin)
- (For Part III) A pair of sacrificial (you will be destroying it) Hifiman stock velour pads, without the mounting rings
- Other basic stuff like pencil/pen/masking tape etc
PROTOCOL
PART I
CORE PLEATHER DAMPING MODS
- The modifications in this segment dramatically increases the damping factor of the Hifiman pleather earpads, clearing up the midrange, which boosts clarity, imaging, and improves the timbre, taking off the nasty midrange “glare” associated with the stock pads. It is the meat of the Jergpad mod compilation. *inspired by Beyerdynamic stock / J$ earpads* -
2. Remove the mounting ring from under the pleather pads; also be sure to remove the ring of hard foam tucked inside the pleathers (and throw the foam rings away; they negatively impact the sound)
3. Flip the earpads inside out
4. How the earpads look after turning them inside out
5. Mark out damping hole spots with a sharpie marker (also shown is a rough diagram of how I lay out the holes pattern)
6. Use sharp scissors or knife to cut out the holes (I try to pinch out the part where a hole is to be cut out, and use scissors); this will take a while to do for all the holes
7. Finished cutting the damping holes; trim if necessary to maximize the hole sizes without compromising the integrity of the fabric (overall took me about 15 mins; will probably take you closer 30 mins if not longer, depending on your proficiency with cutting the holes)
8. Unflip the pads so they are not inside-out anymore, and re-insert the plastic mounting rings; using a pencil or pen, mark out the circle where there is the slight indentation of the mounting ring along the outer edges; trim the rubber flap under the earpads along that guideline, so they no longer go over the mounting ring holes (credit to itshot!).
PART II
‘BACK-VENT’ MINIMOD
- The modifications in this segment slightly angle the drivers to the ears while at the same time lifts the earpads from the drivers slightly, allowing for a more centralized focal point with music but also boosting the openness of the sound; for some it also improves comfort as it slightly distances the ears away from touching the drivers. -
9. Make the 4 tape stacks of electrical or duct tape; I do 2x stacks of 7 thick (for the center two stacks) per earpad, and 2x stacks of 5 thick (for the two flanking stacks) per earpad; totalling 48 strips of rectangles of about 1cm x 0.5cm (that’s ½’’ x ¼’’ for Americans) that need to be assembled into these 8 stacks of tape. All in all the stacks are about 1.5mm~2mm (about 1/10'') in thickness.
10. bond the tape stacks onto the mounting rings; again, the center 2 stacks are the thicker 7-layer tape stacks, and the two flanking stacks are the thinner 5-layer tape stacks
11. If you put these earpads onto the headphone now, orientate the pads so that the back vents line up with the yoke screw facing toward the back of the head if you wear the headphones (hence the name of the mod “back-vent”, haha)
Parts I and II pretty much encompass the version 1 of Jergpad mod in a more refined way, and you can stop here in the jergmod; however, I strongly recommend that you go the extra steps (below) to further improve the pads!
Part III will improve imaging and dynamics drastically, while Part IV will give Audeze-like sub-bass extension. Yeah...better do them 
PART III
‘VELOUR-TOP’ MOD
- The modifications in this segment improve comfort in two ways: via the velour material, and by giving a slightly farther distance with the ears from the drivers to prevent ear irritation. More importantly, it improves the sound quality by breaking the seal of the pleather material, giving a significantly more open and “out of the head” sound, WITHOUT losing the natural tonal balance of the pleathers/jergpads. Dynamics are improved dramatically also. *inspired by Sennheiser HE90 earpads / beaver316* -
*note: steps 15-17 can be alternatively done by sewing the fabric onto the pleathers, if your sewing skills are good.
12. Score / use tape as outline on the velour pads for precision cutting; basically the inside rim cutting will be along the inner seam of the velour fabric contacting the underside rubber material, while the outer cut will be along approx the middle of the vertical portion of the velour fabric, as shown in the photo
13. Cutting into the velours
14. How the cannibalized velour cutouts look like, with a ruler showing the dimensions
15. Add double-sided tape to backsides of the velour cutouts; trim the inside and outside edges of the tape to have them in line with the edges of the velour cutouts
16. Peel away the covers for the double-sided tape
17. Adhere carefully onto the jergpads; trim the edges of the velour top where necessary
PART IV
PAD-CUP ADHESION ‘SUB-BASS’ MOD
- The modifications in this segment have one single goal: to improve sub-bass conduction from the drivers to the earpads. The adhesion of the mounting ring base to the headphone cups with this mod forces full conduction of bass in the range of 15-30 Hz, thus vastly improving sub-bass extension. It is by far the most discreet part of the Jergpad mod, and allows for very secure bond between the earpad and the headphones (some owners complain about stock pads shifting around feeling cheap). *inspired by Audez’e earpad installation methods* -
18. Trace out the double-sided tape with pen, for where they will bond to the undersides of the mounting rings; do THREE per earpad, leaving ¼ of each earpad mounting ring for the backvent mod tape stacks
19. How the double-sided tape looks like once trimmed to the trace pattern
20. Tape the tape cutouts onto the mounting rings, peel off the covers
21. Score out the holes of the mounting ring through the adhesive double-sided tape, and expand those holes with a tool
22. Install the pads onto headphone cups carefully (making sure to line up the backvent tape stacks I mentioned in Part II), and press for the undersides to bond well
RESULT
23. Finished product with all the optional steps done.
HE500 with the full jergpad mod becomes tonally perfect, taking on a slightly romantic sound where bass, midrange, and treble are in just about the right balance with each-other. Imaging is very natural and expands out of the head, and clarity is stellar. Not much more to say really, I just can’t pick on the resulting sound at all, everything is in its right place.
HE400 with the same jergpad configuration also takes on a new life in its sound, the best way to describe its sound would be that it turns very close into how HE500 with velour pads sounds like, except with a punchier bass and slightly more aggressive treble (though nowhere near as aggressive as with velour pads). The biggest factor is that the midrange is pushed forward, and treble is pushed back, and genres like female vocals become much more enjoyable and natural-sounding with this new tonal balance.
Measurements; much thanks to Purrin @ Changstar
1. FR; green = jergpads, blue = velour
2. CSD of jergpads v1.0
3. CSD of velours
(Note that these measurements are with v1 of jergpad!!!!! It does NOT include the changes from Parts III and VI of the current mod version)
Overall much more even and full upper end, less peaks / dips, sibilants would thus be tamed as reflected by my subjective impressions.
Things that are not readily shown by the measurements are that the midrange is much thicker and more satisfying with the jergpads, without the glare/ringing of stock pleathers.
Have fun modding!





















