[whoelse]

Nice! I will do it.

 

[Robotronman]

To test your driver mod, I used pieces of electric tape to seal fhe capsule. This will give you a good idea of the sound result before to really seal wih silicon.

 

[Robotronman]

To test your driver mod, I used pieces of electric tape to temporary seal fhe capsule. This will give you a good idea of the sound result before to really seal wih silicon.

 

[whoelse]

Quote:

The capsules of the cup is screwed and for the drivers, the enclosures are glued with black silicon. The silicon on the HD 428 driver capsules is easy to remove.
 
My recent mod on the HD 428 is to replace the cable with a custom one which I build completly. I used bulk Mogali W2893 quad wire cable and I done a litz braid from the TRS 1/8 to the Y which separe the two cables to both channel. I had to do a hole in the right cup to be able to solder the wires to the passive filter and the driver.
 
I show added a page on my blog about the HD 428 modding but this one is in french. With the pictures you should be able to figure how to do all mods I done. I found my 428 looking classy with the new cable. The sound of my 428 is now very very nice with all the mods I done on it.
 
http://ricomac.wordpress.com/tuning-de-casques-decoute/
 
Enjoy!

 
Hey, I tried removing the capsules but I can't. I use a pen knife to cut the silicon hoping to separate it but it was still stuck there firm. Prying didn't work too.
How did you do it?

 

[Rocko1]

Quote:

The capsules of the cup is screwed and for the drivers, the enclosures are glued with black silicon. The silicon on the HD 428 driver capsules is easy to remove.
 
My recent mod on the HD 428 is to replace the cable with a custom one which I build completly. I used bulk Mogali W2893 quad wire cable and I done a litz braid from the TRS 1/8 to the Y which separe the two cables to both channel. I had to do a hole in the right cup to be able to solder the wires to the passive filter and the driver.
 
I show added a page on my blog about the HD 428 modding but this one is in french. With the pictures you should be able to figure how to do all mods I done. I found my 428 looking classy with the new cable. The sound of my 428 is now very very nice with all the mods I done on it.
 
http://ricomac.wordpress.com/tuning-de-casques-decoute/
 
Enjoy!

Did you use the stock rubber grommet for the cable replacement? Can you post a picture of the cables entering the headphones from the outside?

 

[Rocko1]

Anyone else notice with the tape removed from one hole, the bass is powerful but seems to be one note. It's a bit boomy and inarticulate.
 

 

[Robotronman]

To remove the cup from the driver capsule, use a exacto blade as a pryer. The cup is inserted not too profond into the capsule frame. Insert the blade and try to lift gently one side and do the other one. The silicon is not a hard stuff and could be removed easely after removing the cup. Beware to don't break the cable when lifting the cap, the cable is like 1/2" loose inside the driver. Once the drivers modding is done, put back the cup and glue them with silicon. If you want to add some dampening, just add more silicon arround the cup. For the pictures of the cable entering into the HP, I added them on my blog, just to take a look over it. About the bass mod, I found too the bass too boomy and not well controlled. The high mid could be too present too and the mid not enough present. Adding the filter mod will flatten the frequency curve and the bass will be better, the mid forward and the high in enough quantity. Look in my latest posts, you'll find a link to a pdf of how to add a filter to the hd438 (438 is like the hd428 with the hole mod).

By the way : oh god! How my HP is playing well on my Fiio E17 connected with the LOD to a iPod Video 5,5gen!!

 

[Mad Max]

Quote:

Been working on a detachable cable mod for last few hours, has been quite a pain lol. I cut out the plastic bit to reveal a hole and tried to fit the audio jack and it wouldn't fit so I'm going to use an x-acto knife and start carving away and still a bit uncertain if it'll fit.
 


Going to take a bit of break and update later.

 
You will have to modify the driver capsule.  I would just add in-line (or cable-mount or whatever you want to call it) female jacks outside of the cups and build the replacement cable with a mono mini plug on each headphone lead.  Or install the in-line female jack below the y-split.
 
If you haven't touched the driver capsule filter, add 4mm-thick pieces of open-cell acoustic foam in the cups as I did.  This kills off some of the resonances back there to improve midrange balance and fullness but you will sacrifice a little bit of bass impact.  Totally worth it, I think.  I also added Dynamat Xtreme to the capsule which cleaned up the sound a bit, but it would have been much better to add it to the driver rears directly.  I didn't because I wasn't feeling too confident about busting open the capsule as I'm now reading Robotronman describe.
 
6-7 coats of plasti-dip on the pleather inner side shown here without covering up the ten holes would improve the bass response, detail, and soundstaging as well as improving midrange clarity and detail a little bit.

 

[Robotronman]

Hi Mad Max,

Open-up the driver was easy for me the only thing I add into it, it's the passive filter. I soldered it between the positive terminal and the positive cable lead.

Other than that, I tried to add a layer of isolation mat (2mm) to the back of the drivers and this cut the life of the sound like when I tried the blue-tak mod. Also I tried to add the same layer of isolation mat between the wall ofhe driver cup and the enclosure of the HP and lead me to the same result. I prefer to have some minimal ressonance to have a slightly lifeless sound.

So I decided to leave the capsule with no dampening for now because with the filter, I got a enough balanced and forward sound. I will add a good layer of silicon on the cup joint to glue it to the capsule frame and see the gain.

UPDATE: With a light silicon coat added to the sides of driver cups give me little less resonance and remove nothing.

Guys, doing a mod on a HP is trade off. You may got some gain and you may lost something too. Just experiment one mod at a time and do A-B testing to listen if the mod you had worth the gain vs the lost (if you got one). For exemple, for me, doing the middle hole mod worth nothing without the adding of the passive filter mod.

I look to have more body to the singer voice ex: Radiohead singer voice is on the lean side and lack of body. Any thought?

 

[Robotronman]

In replacement of Plati Dip, you could use Black silicon and add a light coat over the back of the pleather like Mad Max said. I suppose it could do same effect. I listened the two last album of Patrick Watson and I found the mid frequency sounds to be on the lean side. The voice of Patrick is lacking a little of body, Same thing with the voice pf the Radiohead singer when I listen the Amnesiac album. I don't know how to reveal body out of my cans now.
 
What I like of it :
 
Airy sound - could ear the subtility
Openness
Bass
High - could slightly less bright
mid compared to before
45$ cans with a forward sound
more a neutral sound than a warmth one 
 

 

[Mad Max]

You need more treble extension for airiness.  Upper treble boost is one way to get it.
To improve on the mids, try acoustic foam in the cups like I suggested.  Blu-tack isn't a substitute for acoustic foam.

 

[Robotronman]

Madmax: which brand and model of accoustic foam do you sugget?

The frequency i'm looking for are between 1000-4000hz

 

[Mad Max]

I used Akasa Paxmate Plus, and it focuses around 5kHz, but putting it in that rear chamber as I did does not quite have the expected effect.  I think that the headphone in its design regarding its chambers is a bit more like HD280.  That rear chamber functions differently from the main chamber housing the driver element.

 

[whoelse]

I have the 449 and I wanted to share this. If you see the inside of the 400 series, the hole basically function like a speaker bass port which I believe you guys are trying to mod it. If you guys have experience with speakers, basically speakers design with rear bass port are very sensitive to speaker positioning and need a good solid wall to reflect bass. Floor standing might have bass port closer to the floor in addition to rear bass port design. Of course there is front ported design which need space very much like open back headphone. Bookshelves speakers also benefits a lot mounting on a heavy solid stands, you get tighter music, better definition and separation kind of thing. If you place a speakers on a hollow bookshelves or table you started to hear boomy bass or defuse sound if you know what I mean.
 
Back to 400 series, inside the headphones, these holes are basically bass port. It deflect bass and because the outer shell of the 400 is actually quite thin. The bass produced is more or less not to it's optimum performance. If you play music and if you feel the outer shelve the vibration is quite hugh. Basically the back of headphones does store energy and different material such as plastic, wood or metal will affect the sound.
 
Tyll explain this on the HD25-1 II vs Amperior:
 

 
Based on my many years of experience with speaker systems, my objective to improve the sound of 449 is simple. Improve the material of the 449 outer shelves so it is firmer, less resonant and give more focus in sound especially treble as well as better definition and impact to the bass.
 
I bought some black tac (black version of blue tac, black one is softer and more stretchy too) which I use to improve my Grado. I will talk about it separately in Grado thread. I wanted to open up the inner capsule but failed to do so. So I started of to reinforce the outer shelves to metal.
 
I bought a sheet of aluminum foil from Art & Craft store and cut out the shape (some trimming needed) so it is the same shape inside the outer shelves behind the bass port. I spread a very thin layer of black tac adhesive material to hold it in place. The black tac in between also act as insulation material to absorb vibration and resonant. Now by tapping the back of the headphones, it is no longer hollow sound. It is much solid than the bare shelve.
 
I also realized the space between the inner capsule and the outer shelves is very small, since I failed to open the capsule (I still think if I can spread a thin layer of back tac on the inner capsule wall, add a thin layer behind the metal magnet-tricks grado did to RS2 and higher) I rolled some black tac on the outer capsule to it will stick on to the outer shelves. You don't have to put too much just strategically and please do not block the bass port. What this does is that the capsule is not more or less one piece integrated to the while headphones and with the black tac active as insulating material against vibration the sound will be very focus. Somehow the 449 driver has it's potential, I feel the separation is actually very good and the sound signature is very clear.
 
The mod will give you better, tigher bass. The treble will also improve quite a bit. It no longer feel like a good speakers position wrongly or sitting in a hollow bookshelves (thin, hollow plastic back).
 
What do I benchmark with? The HD650, MS2i and SRH840 are some of the best headphones I have and before the mod, these are clearly better than the 449. After the mod, I have achieve what I initially plan for, to bring out the potential of the 449 and I can now confidently said the comparing with the SRH840 and MS2i the 449 feel it is on the same league although each of them has a different sound signature which there is no way to say which is better (Although I would say HD650->MS2i->SRH840|HD449).
 
Previously I always feel that the 449 while good is a lower league model than the MS2i/SRH840. The bass while clear seems missing that little something, treble might be a little too dull and the mid is clear but de-focus. It is the same way like I said base on my experience with speakers without a proper stands or position at the wrong way.
 
Try it, watch Tyll video above and see what I am trying to say. Too bad I didn't take any photos especially the metal disc I made to reinforce the back.

 

[GetEvry1Rdy]

Hey guys, I'm extremely new here, but I've been snooping on these threads for a bit now. This is, by far, the best place for information on decent cans and such. With that said, I just got a pair of HD 439 as my starter cans. These things are great out of the box. A crisp and clean sound. Much better than the other cheap stuff I've been using. I did the bass mod to these using this guide. The results are fantastic. I feel as if these were supposed to cost a lot more, now. I'm not complaining, though. Mad respect to wje and everyone else he credited. My start of "listening" to music has now truly started.