# 3D printed closed headphones with HD800 driver



## frank2908 (Aug 15, 2018)

As a long time head-fi follower of modding headphones, like many people here, I've tried 2 of the most popular headphones mod: the grado cup mod (in aluminium) and fostex T50RP (aluminium cup mod with Audeze/Kennerton earpads)

 Now it's time to try something new, to my knowledge, no one has tried customizing the HD800 before, so I've got to try it.
 To start with, before starting the project, I've only auditioned the HD800 for 5 minutes, but based on the reviews the treble can be quite hot. My inspiration for this build is the sony R10, which some guy mentioned that has deeper soundstage than the hd800. So I knew a closed (or semi closed) headphones with great soundstage is possible.
 Here is a sneak peek of the final (until now) prototype:



 I bought a pair of replacement driver online and started to design the cups and baffle. The headband was taken from a superlus hd660. And eagerly I asked fellow head-fi member Rudy- Calico88 to CNC the cups from rosewood. Seeing his work on pictures, I had no doubt it would be good.

*First prototype:*
 I know it is silly to make the first prototype of your headphones in very expensive material. The build quality of the cup from Rudy-from the tolerance, to the quality of the wood and the finish is top notch. I designed the baffle with lots of hole to tune the sound by covering them with tape.






 The cup was then dampened with dynamat. Note that the in the middle of the cup there is a removable disc for open/close conversion.

 First listen: It really showed me the potential of the driver. The hd800 is well built, it weight 35g compare to the plannar driver of fostex at 45g.
 The treble detail is there, but with tuning, either I get a good soundstage but no bass or vice versa. Also the soundstage width is very good but not the depth. I spend 2 months playing with this and came to a conclusion: I made a mistake in the design: the cup's volume was too big, and even though the audeze pad is angled, the driver mounted flat on the baffle does not create a deep soundstage. Then came the difficult decision: I have to abandon the beautiful rosewood cup. At the same time, my Printrbot SImple Metal 3D printer arrived, I knew I have to change the design.

 Second prototype:
 Still in love with the wood cup, I decided only to ditch the rosewood baffle for a new design, this time incorporated an angled driver relative to the baffle. The baffle protrude deep into the cup, therefore reduce the volume inside the cup. This new baffle is 3d printed from ABS. The baffle is left undamped ( not with dynamat or blu-tack)




 Sound impression: The soundstage and bass is good, but there is a weird mid. I suspect there is a reflection on the ear side of the driver, due to a large volume created by this new baffle.
 Now I have to decide to remove the driver from this beautiful cup to a fully 3d printed cup. On the new design, I also want to make the cup less deep. I made a mistake designing 2 huge drums stuck on my head.


 Final prototype:
 WIth the inspiration come from the SOny R10 and the speaker B&W Nautilus, I want to design the cup without the concentric shape and inspired by a sea creature. Behold the sea shell cup.






 The 3d printed cup was in grey, then bottle sprayed black.The design of the baffle also changed( it's the grey disc in the next picture). With new design, there is no reflection of sound on the ear side of driver.
 I later spend 3 months listening and tweaking the sound, by opening/closing venting holes on the baffle and cup, damping the cup with blu-tack ( i will switch to dynamat later). After the dynamat, there is a layer of lambskin leather and cotton wool to further damp the driver.
 THe jack is mini XLR from Rean.
 Sound impression: (briefly compared to a hd800 in a showroom)
 Now I'm totally satisfied with the sound. By mass damping the baffle and and cup, the sound is not bright. To my ear, the quality of the bass and mid is mostly the same as the stock hd800. However I am most proud about the soundstage. Although is closed ( or semi closed due to vents), the soundstage is not as wide but deeper than the hd800, as a result of extremely angled driver (angled ear pads + angled driver from baffle).
 Now I know this is not the final prototype, because tuning headphones make you listen to them for a long time. As a result your ear becomes used to the sound. Therefore sometimes I have to go to the shops to compare to other headphones, and it takes time.
 THe final pic is the headphones with different ditched component. Now I'm not throwing the rosewood cups away, still waiting for the next project.



 Edit: new pictures of the build:

 I made the cable from Double Helix Cable Nucleotide, Switchcraft 3.5mm jack (so I can use with my dx90 conveniently) and rean tiny XLR. For mini XLR, I think Rean is a good choice for it's aesthetic and affordability. The terminals are easy to solder. I use a plastic sleeving for speaker cable, similar to Techflex, but more coarse, you can see the braiding through the sleeves.

 A clear shot oy the yokes assembly. The stock yoke from the Superlux HD660 is too small (the same size as Beyerdynamics), so I made a new yoke from stainless steel.I cut the shape from 2mm steel plate, then grinded and polished by dremel.
 The hinge of the yoke (small rectangular plastic thing) is 3d printed from carbon fiber abs, glued on to the yoke. Then I use M3 socket head screw to attach the yoke to the cup.

 There are 3 holes near the mini xlr connector. I designed the cups with vents at the front, but I need to drill extra 3 holes for tunning.

 I used similar method to the Denon Markl mod, adding foam to the thicker side of the pads and cotton to the thinner side. It just sound good to my ears in this config. Also note the 2 holes I punched out of the earpads, helps thinning the mid.

 The naked shot: the baffle is 3d printed from 3 parts, saving me from printing in 1 go and spend days removing the supporting materials. THe white blutack is there to mass damp the baffle and reduce reflection from the driver. There are small vents connecting to the main cup chamber. this reduces the pressure and again helping the soundstage, but too many open vents and the sound becomes thin with peaky treble.
 There is also a lip for mounting the Audeze earpads.

 Final pics showing the beautifull hd800 driver and my crappy craftsmanship with lots of blu-tack

---13th Oct 2016 update------
Version 3 update:
Finally got a long holiday and had enough time to finish the new prototype.
Unfortunately I could not make these out of carbon fiber, since I don't have enough time. Also last time I played with carbon fiber, turned out the epoxy I have hardened too fast ( 10 mins), therefore i can't do resin infusion or even normal lay up because of lack of time for air bubble to disappear.
The earpads are mounted on plate with magnet attached, similarly there are magnets on baffle,
Every parts are made from Carbon fiber High PLA filament from FIlabot
weight: 400g without cable ( the last prototype weight 500g). Without dynamat, only weight 330g


 
Old design, driver at a small angle, and remain in the center of the ear pad opening.



 
New prototype driver mod

resonator made from 3d printed Brass PLA from colorfab, I can get the exact dimension , also the brass plastic is quite heavy, so it will damp the plastic protector. I had to take the driver apart and cut the screen off the center hole


 


 
the driver is at 35 degree from the baffle plate and push as much forward as possible
the baffle is lighter and has lots of opening. They are then covered with Micropore tape (white)


 
Another view of the extreme angled driver.


 

The backside of the baffle and the cups is covered in Dynamat, then one layer sound absorbing foam similar to Akasa Paxmate. The holes/ openings are covered with micropore tape.
Mini XLR connectors.



 



 



 



 

The Carbon FIber PLA is really stiff, strong and look really nice. It has a matt finish and looks really cool. On the left is carbon fiber PLA, right is normal PLA

Finish


 


 



 

3D printed HD800 in Carbon fiber PLA
I was too lazy to make a new headband assembly from scratch, so I used an old Fostex T50rp headband.

The connector will be covered in Black Sugru. I don't want to make a chunky and heavy 3d printed cover or housing for those connector. So it is kept simple.
Sound improvement:
Because the driver is much more forward and angled, the image of this can really improved. It is now very pin point. But there is still issues with lacking bass.
---14th Aug 2018 update------
My latest version, V4
I completed this last year actually but never posted since I traveled round the world for 1 year, so left this baby at home and just picked them up last month. I have a new design but my 3d printer broke and I'm on the road again,anw these sounds great with Chord Mojo





It's the first time I switch to open ear design, and there is a removable magnetic cap to convert to closed (not shown in photo). There is a dust screen cut off from stax sr007 earpads fabric. The driver cover is printed with honeycomb pattern








On the baffle and earpads rings there are magnets so I cant swap pads easily. Now I have the diy Stax pads (Sr007 with memory foam fill ) and Shure Alcantara earpads. The Stax produces a better soundstage and a bit more comfy because the memory foam I used is very soft, but if I'm not in a room with AC, then I switch to Alcantara pads. The alcantara has a bit smaller soundstage but better bass (tiny bit)




The baffle is left open and sealed with 3M Micropore tape, which has the best balance between sealing (more base) and open (soundstage) IMO.
The original idea of making the headphones with huge closed cup like R10 and HD800 driver failed, not because of the cup but because the volume between the driver and the ear was not big enough, and the hd800 are designed for this huge volume. Now I plan for next build to be convertible between open/closed and over ear/ on ear. When you have an expensive headphones and a Chord MOjo, why do you have to buy another portable headphones? I believe to make a convertible portable hd800 would sound at least better than any $500 portable headphones anyway


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## Oregonian

Congrats!   Amazing work and I'm going to follow this thread for the next iteration(s). 
  
 Thanks for sharing.


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## frank2908

Thanks, for now the next modification I can think of is to make the mini XLR socket on the headphones smaller, it looks a bit out of proportion in my opinion. I'm considering 2.5mm mono plug- a la HD700. But so far I can't find a good but cheap 2.5mm connector with strain relief, I afraid the thin connector would break on this headphones. Also the Audeze earpads look ridiculously thick, I tried the Kennerton earpads which looks good, but the leather is too hard can does not seal well, therefore blured the mid.
 I have cut out my own angled earpads from very soft memory foam, and have a piece of lambskin laying there, but I'm hopeless at sewing. Hopefully one day I'll learn how to make leather earpads.


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## kapanak

Amazing work. Quite inspiring I must say  And you're right, nobody I know of has attempted a headphones from scratch using HD800 drivers before, much less a closed headphones.
  
 I actually going to order a pair of replacement HD800 drivers online for something similar to what you're doing. But then again, $500 for a pair of drivers is a VERY high cost of entry for DIY headphones lol ... I happen to have access to fully featured physics laboratories in a university, so I can do some acoustic analysis and imaging as well to optimize a cup  Just as you say, a great closed headphones is possible, and just not done. Not enough research. DIY it is


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## frank2908

kapanak said:


> Amazing work. Quite inspiring I must say  And you're right, nobody I know of has attempted a headphones from scratch using HD800 drivers before, much less a closed headphones.
> 
> I actually going to order a pair of replacement HD800 drivers online for something similar to what you're doing. I happen to have access to fully featured physics laboratories in a university, so I can do some acoustic analysis and imaging as well to optimize a cup  Just as you say, a great closed headphones is possible, and just not done. Not enough research. DIY it is


 
 The Sony R10 is an evidence that it exist, but at that price for most people, it is nothing but a myth (
 Also if you order the driver, be carefull not to solder the cable to the driver for long. I made a mistake melting the solder post into the plastic and broke the extremely thin wire connecting to the voice coil. I was scared as hell but then managed to fix it by soldering the thin wire back together.


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## kapanak

frank2908 said:


> The Sony R10 is an evidence that it exist, but at that price for most people, it is nothing but a myth (
> Also if you order the driver, be carefull not to solder the cable to the driver for long. I made a mistake melting the solder post into the plastic and broke the extremely thin wire connecting to the voice coil. I was scared as hell but then managed to fix it by soldering the thin wire back together.


 

 Question: Did you order directly from Sennheiser?


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## frank2908

i ordered from www.custom-cable.co.uk


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## rfan8312

Great work! Inspirational. Congratulations.


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## chinsettawong

Nice!


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## Mahdi8

Oh wow. A closed hd800 is the dream for me


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## koiloco

^ Dang.  Very nice work.  If you started back in December of last year, I could have paid you a visit in person.


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## nw130d

Great stuff, true hobbyist!
  
 Personally always wanted to 3D print closed cups for the HD700. But the 3D printer and measurement tools adds up astronomically!
  
 Side note some companies like Inventables are making small CNC machines that runs a Dremel so one in theory can produce any wooden cups they want.


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## frank2908

To put to perspective, my first prototype in rosewood cost more than the 3d printer. The cost for a desktop cnc is comparable to a printer, but exotic wood cost significantly more than 3d printed plastic. Plus since it is additive manufacturing, you need less material than traditional machining.
Diy wise both requires lots of experience, cutting with wood might result in wood burn, you have to play with the speed and feed rate. For 3d printing, you have to play with many setting for different material and you have to damp afterward. Ideally wood is acoustically better , therefore I'm interested to learn methods for creating liquid wood like the audioquest nighthawk. I can make the mould out of the 3d printer.i also have carbon fiber laying around but given the resonance, I have to add mass damping material anyway. It will not be light, therefore the only purpose for carbon fiber is aesthetic.
Anyone know how to mold wood/plastic or epoxy composite?


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## frank2908

koiloco said:


> ^ Dang.  Very nice work.  If you started back in December of last year, I could have paid you a visit in person.



You mean in December 2013? At that time only the driver has arrived.  you are welcome the next time you are in Vietnam


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## koiloco

frank2908 said:


> You mean in December 2013? At that time only the driver has arrived.
> 
> 
> 
> ...


 
 No, December 2014.  It could have been fun. I will probably visit next summer.  If I do, I will PM you.


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## nw130d

frank2908 said:


> To put to perspective, my first prototype in rosewood cost more than the 3d printer. The cost for a desktop cnc is comparable to a printer, but exotic wood cost significantly more than 3d printed plastic. Plus since it is additive manufacturing, you need less material than traditional machining.
> Diy wise both requires lots of experience, cutting with wood might result in wood burn, you have to play with the speed and feed rate. For 3d printing, you have to play with many setting for different material and you have to damp afterward. Ideally wood is acoustically better , therefore I'm interested to learn methods for creating liquid wood like the audioquest nighthawk. I can make the mould out of the 3d printer.i also have carbon fiber laying around but given the resonance, I have to add mass damping material anyway. It will not be light, therefore the only purpose for carbon fiber is aesthetic.
> Anyone know how to mold wood/plastic or epoxy composite?


 
 Just do a search on google "3d print wood filament" there are many types. Barnacules has a youtube video on one type of wood filament.


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## frank2908

I have triedwood filament from colorfabb, but it turned out too soft for a headphones cup or baffle. A 5 mm thick baffle from this material can be bended by hand. Plus it does not look as nice as the audioquest nighthawk. The nighthawk is made from aborform, but this company only supply pellets that seemsto be ordered in large number.any recommendation for other cheap source of diy molded wood composite?


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## nw130d

Assume you are talking about industrial plastic pellets? Even if they sold average consumer the pellets, it be useless. One would need plastic injection molding machine, also custom made injection mods for the plastic to be injected into...
  
 Another idea is you can use wooden fibers in thin shavings, mix it with Epoxy resins stuff you have to mold carbon fiber will work. Print 2 opposite negatives with 3D printer... example print first cup 110% (1.1:1) and the other cup 90% (0.9:1). Take the wood shaving mixed with resins squeeze it in between the 110% cup and 90% cup. Let it cure and you should have 100% (1:1) right sized wood/epoxy cup.
  
 Or easier might be try a stronger wood filament, as ^ would takes a lot load of work
  
  
  
 "wooden fibers in thin shavings" as in...


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## Hal X

Awesome work!!! Could you please post more pics of the final result (for example showing inside the pads) and more in depth analysis of the sound? Somebody should measure them!
  I think that the cup should be shaped so that the center hole of the driver is actually left vented to the outside (horn shaped cup kinda) to keep good bass extension, while the rest of the driver is enclosed and properly damped. Also I think part of the front of the driver should be damped. The HD 600/650 drivers have part of the driver (the cone)  directly eposed and part (half or more I'd say) front damped. Result? No peaks.

 As you can see only a small part of the circumference of the transducer is left exposed.
 Take HD700s instead, there's no front dampening and you have a weird peak.

 Something like that mesh used in HD600 would be perfect.


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## InsanityOne

This is truly amazing... A custom closed-back HD800? If only you could mass produce the final model somehow... I would buy one in a heartbeat. I can't wait to see more! 
	

	
	
		
		

		
			




  
 P.S. - How do they fair with amping? I'm assuming since it is the same driver it is still as picky as the stock HD800?


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## takato14

Oh my god. Tyll. You have to measure this.


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## kapanak

takato14 said:


> Oh my god. Tyll. You have to measure this.




Once Frank considers his work done and his final iteration complete, he should definitely send them to Tyll for measurement. :O


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## Bill-P

Hey, frank2908, nice project!
  
 I'll be in Vietnam in June (2015), so if you have time, we can meet up and compare notes on modding. Will most likely bring my modded Sony Z7 and Audeze LCD-2, so you can check them out.


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## frank2908

hal x said:


> Awesome work!!! Could you please post more pics of the final result (for example showing inside the pads) and more in depth analysis of the sound? Somebody should measure them!
> I think that the cup should be shaped so that the center hole of the driver is actually left vented to the outside (horn shaped cup kinda) to keep good bass extension, while the rest of the driver is enclosed and properly damped. Also I think part of the front of the driver should be damped. The HD 600/650 drivers have part of the driver (the cone)  directly eposed and part (half or more I'd say) front damped. Result? No peaks.
> 
> As you can see only a small part of the circumference of the transducer is left exposed.
> ...


 
 The HD800 driver is a ring design, so the back of the driver has no holes. I made the cup with quite a large internal volume and lots of vents/bass port for tuning. Similarly on the ear side of the driver, the center of the driver is a hole, so if you cover the circumference, all the sound is blocked. I think Sennheiser designed the driver with this issue in mind, so the ring design would solve the problem of peaks. However the peak comes when they made the headphones extremely open and use extensively the steel mesh. I have no experience with the material but I suspect its the source of treble peaks.


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## frank2908

kapanak said:


> Once Frank considers his work done and his final iteration complete, he should definitely send them to Tyll for measurement. :O


 
 I'm a bit hesitating to send him a headphones full of blutack  But definitely it's on my next do to list  
  


bill-p said:


> Hey, frank2908, nice project!
> 
> I'll be in Vietnam in June (2015), so if you have time, we can meet up and compare notes on modding. Will most likely bring my modded Sony Z7 and Audeze LCD-2, so you can check them out.


 
 Sure. How did you mode your sony z7? I'm interested in any headphones mod, there are new ideas that I haven't try yet.


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## Shurephile

Funny how the admin quoted this page as "DIY Modified HD800's," when in fact all they are, are headphones with HD800 drivers.


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## takato14

shurephile said:


> Funny how the admin quoted this page as "DIY Modified HD800's," when in fact all they are, are headphones with HD800 drivers.


 
 who cares


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## Bill-P

frank2908 said:


> Sure. How did you mode your sony z7? I'm interested in any headphones mod, there are new ideas that I haven't try yet.




I added reflections to bring back some high frequencies, and then applied some reflection dampening to reduce low mid warmth. But the greatest change comes from mass loading. Essentially increasing baffle rigidity using more than just dynamat. This helps dampen excess vibration in the whole structure at low frequencies, and it also helps offset the strength of the magnetic field for more precise control of the diaphragm at these frequencies. As a result, there is more transparency across the board.

My Z7 will most likely get measured against the stock pair soon. Will work on it even more when I get it back, as the current version is still just a test bed for this new mass loading mod. Originally, I used blu-tack and dynamat for this task, but I have since resorted to more... extreme materials.

I was hesitant to state anything, since theory may not always become reality, but impressions from other Head-fi'ers who have heard the first few prototypes gave me more confidence in the applicability of this mod. Purk currently has my pair, and he thinks it is very obviously different from stock where transparency and soundstaging are concerned. If we meet in the summer, I can give you a full breakdown, and you can also listen for the effect.


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## penmarker

Any chance we could see the insides of the 3D printed ear cups? I'm interested to see the dampening and internal design of the cups. I've honestly never seen the insides of a Sony R10 or other TOTL woodie cans like TH600/TH900, D2k/D5k/D7k, or W1k/W3k/W5k. That would be really really cool.


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## frank2908

bill-p said:


> I added reflections to bring back some high frequencies, and then applied some reflection dampening to reduce low mid warmth. But the greatest change comes from mass loading. Essentially increasing baffle rigidity using more than just dynamat. This helps dampen excess vibration in the whole structure at low frequencies, and it also helps offset the strength of the magnetic field for more precise control of the diaphragm at these frequencies. As a result, there is more transparency across the board.
> 
> My Z7 will most likely get measured against the stock pair soon. Will work on it even more when I get it back, as the current version is still just a test bed for this new mass loading mod. Originally, I used blu-tack and dynamat for this task, but I have since resorted to more... extreme materials.
> 
> I was hesitant to state anything, since theory may not always become reality, but impressions from other Head-fi'ers who have heard the first few prototypes gave me more confidence in the applicability of this mod. Purk currently has my pair, and he thinks it is very obviously different from stock where transparency and soundstaging are concerned. If we meet in the summer, I can give you a full breakdown, and you can also listen for the effect.


 
 I agree with you, mass damping is the most important thing to do for me if you use plastic or aluminium as a material for cup and baffle. Wood on the other hand need little or none mass damping because the resonance of wood cause coloration that is frequently desirable. I would love to hear more from you about the "extreme material"
 Now time for some more pics:

 I made the cable from Double Helix Cable Nucleotide, Switchcraft 3.5mm jack (so I can use with my dx90 conveniently) and rean tiny XLR. For mini XLR, I think Rean is a good choice for it's aesthetic and affordability. The terminals are easy to solder. I use a plastic sleeving for speaker cable, similar to Techflex, but more coarse, you can see the braiding through the sleeves.

 A clear shot oy the yokes assembly. The stock yoke from the Superlux HD660 is too small (the same size as Beyerdynamics), so I made a new yoke from stainless steel.I cut the shape from 2mm steel plate, then grinded and polished by dremel.
 The hinge of the yoke (small rectangular plastic thing) is 3d printed from carbon fiber abs, glued on to the yoke. Then I use M3 socket head screw to attach the yoke to the cup.

 There are 3 holes near the mini xlr connector. I designed the cups with vents at the front, but I need to drill extra 3 holes for tunning.

 I used similar method to the Denon Markl mod, adding foam to the thicker side of the pads and cotton to the thinner side. It just sound good to my ears in this config. Also note the 2 holes I punched out of the earpads, helps thinning the mid.

 The naked shot: the baffle is 3d printed from 3 parts, saving me from printing in 1 go and spend days removing the supporting materials. THe white blutack is there to mass damp the baffle and reduce reflection from the driver. There are small vents connecting to the main cup chamber. this reduces the pressure and again helping the soundstage, but too many open vents and the sound becomes thin with peaky treble.
 There is also a lip for mounting the Audeze earpads.

 Final pics showing the beautifull hd800 driver and my crappy craftsmanship with lots of blu-tack


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## acain

That is truly hard core DIY


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## doublea71

frank2908 said:


> You mean in December 2013? At that time only the driver has arrived.
> 
> 
> 
> ...


 

 Hey Frank, I'm in Phu My Hung, District 7 - I'd love to hear these sometime!
  
 Cheers,
  
 Aaron


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## frank2908

doublea71 said:


> Hey Frank, I'm in Phu My Hung, District 7 - I'd love to hear these sometime!
> 
> Cheers,
> 
> Aaron


 
 Haha this is where I live also. Just PMed you. Maybe someone can post an impression of my headphones after all.


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## doublea71

frank2908 said:


> Haha this is where I live also. Just PMed you. Maybe someone can post an impression of my headphones after all.


 

 This is so crazy - I got your message. We're practically neighbors! Such a great website...


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## yen262

Oh god, I wish I have a chance to try on these modded headphones. Great job, you can build your own and sell, I will buy one~


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## Jeff Y

Wow these look amazing. I'm going to try modding this sumer too when I get my guts together.


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## Hal X

frank2908 said:


> The HD800 driver is a ring design, so the back of the driver has no holes. I made the cup with quite a large internal volume and lots of vents/bass port for tuning. Similarly on the ear side of the driver, the center of the driver is a hole, so if you cover the circumference, all the sound is blocked. I think Sennheiser designed the driver with this issue in mind, so the ring design would solve the problem of peaks. However the peak comes when they made the headphones extremely open and use extensively the steel mesh. I have no experience with the material but I suspect its the source of treble peaks.


 
 I meant the center hole of the ring. There is only some mesh inside that hole and in the original HD800 configuration it is comunicating with the outside as you can see.


 I do not mean that all of the front of the driver should be dampened of course, and of course being it a ring configuration the center is a hole. I mean that half of part of the trasducer ( excluding the center hole) should be frontally dampened. Approximately from the outer circumference to the middle inner circumference, the one between the outer one and the center ring.

 Or maybe one could do the opposite and cover the center hole and the part from the ring to the inner circumference. The hole may be acting as a resonator.


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## Dukei

nice looking, how do the sound?


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## chupacabra314

Might be a bit too late but if you want to get rid of the rough edges from the 3d printing and give it a nice polished piano look you can look at acetone polishing.
  
 I used to do this for 3D printed ABS plastic prototypes for work but it's a bit dangerous as you need to heat up acetone and then hold the 3d printed part in the fumes for 15-20 mins. The effect is stunning if you can pull it off.


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## Tyll Hertsens

frank2908 said:


> I'm a bit hesitating to send him a headphones full of blutack  But definitely it's on my next do to list


 
  
 Definitely happy to do it where you're ready.


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## frank2908

chupacabra314 said:


> Might be a bit too late but if you want to get rid of the rough edges from the 3d printing and give it a nice polished piano look you can look at acetone polishing.
> 
> I used to do this for 3D printed ABS plastic prototypes for work but it's a bit dangerous as you need to heat up acetone and then hold the 3d printed part in the fumes for 15-20 mins. The effect is stunning if you can pull it off.



Thanks. I have been using this method for different objects, but these cups and baffle were printed in pla, and so far all my friends like the layered finish, so I didn't bother. I'm also aware there is a similar method for pla but not using acetone, but havent tried it out


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## n3rdling

I don't think most people really appreciate how amazing this DIY is.  Really great stuff, keep it up.  Can't wait to see the measurements!


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## mrscotchguy

n3rdling said:


> I don't think most people really appreciate how amazing this DIY is.  Really great stuff, keep it up.  Can't wait to see the measurements!




Agreed, wholeheartedly. Sitting on the edge of my seat, keep up the great work!


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## remilio

This is the most insane (in a good way) headphone mod I've ever seen. Great job!


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## Shurephile

n3rdling said:


> I don't think most people really appreciate how amazing this DIY is.  Really great stuff, keep it up.  Can't wait to see the measurements!


 
  
 It is when done correctly.


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## frank2908

There is something for me to play with for the next iteration:
 http://3dprintingindustry.com/2013/12/24/kai-parthy-gets-felty-foamy-porous-poro-lay-line-filaments/
 I have this material at hand but has been too lazy to print an earpads out of this. I want to achieve the same angle shape as the Audeze pads, but with larger opening (inside diameter) with a more circular shape, so that I can push the driver even a bit further forward. The problem is this filament would be potentially good for the core of the earpads, but the cover has to be made out of lambskin. I also have a piece of lambskin laying around, but have to skill of stiching/sewing. Could any one please post a pictorial tutorial for making leather earpads?


----------



## Bill-P

If you're considering making ear pads, I'd note:
  
 - Bigger opening generally gives a greater sense of soundstage height, and gives the user a bit of breathing room.
 - Distance from ears to driver (perpendicular to the skull) will determine soundstage width.
 - Angle of driver and distance will determine soundstage depth.
  
 Generally, I think you'd want more of all of those (within reasons), unless you're after a more intimate sound.
  
 Also make sure you damp the "lip" of the enclosure where the driver is angled or you may get reflections that cause oddities in frequency response.
  
 I suspect you won't finish all of this in before I get back to Vietnam, so... if that happens, I hope we can meet up and discuss more there.


----------



## HiFiChris

Clean job, congrats! 
	

	
	
		
		

		
		
	


	



  
 Measurements would be nice though - maybe you should send them to Tyll.


----------



## penmarker

So... Any pictures of the insides of the cups?


----------



## frank2908

hal x said:


> I meant the center hole of the ring. There is only some mesh inside that hole and in the original HD800 configuration it is comunicating with the outside as you can see.
> 
> 
> I do not mean that all of the front of the driver should be dampened of course, and of course being it a ring configuration the center is a hole. I mean that half of part of the trasducer ( excluding the center hole) should be frontally dampened. Approximately from the outer circumference to the middle inner circumference, the one between the outer one and the center ring.
> ...


 
  
 I tried placing the foam ring of the AKG k701 ( similar to your third picture where the outer circumference is covered) on the driver but I did not like the sound. Not that I my headphones need to tame the treble, just to test the effect on this headphones. The treble is indeed tamed, and mid bass increased a tad, but imaging decreased and the sound is not lively anymore.


bill-p said:


> If you're considering making ear pads, I'd note:
> 
> - Bigger opening generally gives a greater sense of soundstage height, and gives the user a bit of breathing room.
> - Distance from ears to driver (perpendicular to the skull) will determine soundstage width.
> ...


 
 I totally agree with you regarding the earpads. On my first build, the driver is not angled relative to the baffle, and I thought to myself " this is not the soundstage the HD800 is famous for". That lead to the current design with extremely angled driver. I plan to make the new earpads with the same angle, bigger opening but lest depth because at the moment the headphones look ridiculous. I would never sacrifice sound for the look of the headphones, but if I can do both then I should.


----------



## knowhatimean

hal x said:


> frank2908 said:
> 
> 
> > The HD800 driver is a ring design, so the back of the driver has no holes. I made the cup with quite a large internal volume and lots of vents/bass port for tuning. Similarly on the ear side of the driver, the center of the driver is a hole, so if you cover the circumference, all the sound is blocked. I think Sennheiser designed the driver with this issue in mind, so the ring design would solve the problem of peaks. However the peak comes when they made the headphones extremely open and use extensively the steel mesh. I have no experience with the material but I suspect its the source of treble peaks.
> ...


 
 Having just removed the actual grilles (a few days ago) I'm 99.999% certain that is what is causing the most resonance inside of the HD800 are those grilles resonating straight back to the metal ring you're looking at, as that ring is sitting over the edges of the grilles
 holding them down.
  
 I listen to Orchestral music most of the time,I was pretty shocked (& continue to be so) at how much more distinct inner soundstage
 information I can now hear, Maybe adding some "resonance" to other non Acoustic based music genres adds some "excitement"
 for Acoustic based music it detracts from the listening experience. I have to believe that Sennheiser heard how the HD800 were characteristically "Bright".( I guess this "works" for a lot of people)
  
 I had been listening to my 800s w/ the Anax 2 mods (which I placed back after I removed the grilles) but minus the grilles I think the
 sound characteristics have come together to the point I can hear if other parts of my listening chain could use some attention.
  
 It would be totally ignorant of me not to acknowledge frank2908 all the unbelievable work he's done to create the "Frank2908
 Headphone" as this appears (for the most part) to be a "clean sheet" new build headphone that uses the HD800 "driver"'
  
 The title of this thread on the Home page could use some revision


----------



## frank2908

Just finished a new cable for my headphones, I used cheap 26 awg copper cable from btg audio and rean mini xlr jack as I don't want to spend too much on cable. I believe spending $200 plus for a cable would not deliver as much change as tuning the headphones (cup, baffle, pads) themself. The cable is 8 wire braided, even though its cheaper than my DIY DHC nucleotide, the sound difference is not much, only the mid is a tad thinner than the DHC cable.

 Supprise, my new set of HD800 drivers arrived. Now I'm still unclear what to do next with them: 
 1 Create the same headphones so I can still enjoy them while sending one set to Tyll for measurement?
 2 Create an open headphones? I doubt that I can make an open headphones better than stock
*3 Going crazy: 2 drivers on one side, padless to compete with K1000???????*

 At the bottom are the driver for my next test, I ordered  some drivers from aliexpress to build portable headphones. From left to right:
 40mm carbon drivers -initial test is good, solid bass even without pads.
 50mm silk and wool driver- best of the bunch so far, good bass while remain tight, tiny brightness but can be damped
 50mm titanium coated driver- most detailed driver of the bunch from aliexpress but too bright.
 40mm gold coated driver.-just too bright but MY GOD IT'S BLING.


----------



## takato14

frank2908 said:


> At the bottom are the driver for my next test, I ordered  some drivers from aliexpress to build portable headphones. From left to right:
> 40mm carbon drivers -initial test is good, solid bass even without pads.
> 50mm silk and wool driver- best of the bunch so far, good bass while remain tight, tiny brightness but can be damped
> 50mm titanium coated driver- most detailed driver of the bunch from aliexpress but too bright.
> 40mm gold coated driver.-just too bright but MY GOD IT'S BLING.


where the hell are you ordering these from

like specific sellers or listings would be nice


----------



## frank2908

http://www.aliexpress.com/store/group/Headset-speaker-unit/323026_258245270.html


----------



## kapanak

takato14 said:


> where the hell are you ordering these from
> 
> like specific sellers or listings would be nice


 

 Hahaha you read my mind XD Frank is a wizard.


----------



## fleasbaby

frank2908 said:


> http://www.aliexpress.com/store/group/Headset-speaker-unit/323026_258245270.html




Okay, that place looks awesome. I am an Ali-noob though. At the risk of going OT, what's the best way to buy if you're in the US?


----------



## frank2908

fleasbaby said:


> Okay, that place looks awesome. I am an Ali-noob though. At the risk of going OT, what's the best way to buy if you're in the US?


 
 So far all of the items I ordered from Aliexpress have arrived on time, and all of them are shipped free. The delivery in return is quite slow (processing + shipping takes 3-4 weeks)
 The customer service is good, they often response in 1 day in Google translated english.
 I odered most of the "exotic" driver material they offer (non mylar- too popular): titanium and gold coated, carbon, wool and silk in one driver. From the first impression, the metal coated one is too bright, and they seem to use only one or two types of magnet, so don't expect very detailed driver delivered from very strong magnet like the testla from Beyer or Hd7/800 level.
 When I start to play with them, I will start another thread to give my final recommendation.
 Now let's go back to the main topic!


----------



## Defyant

Hey Frank Much respect mate  totally pro work 
  
 i'm voting for the Going Crazy  
  
 I almost ordered the 40mm Carbon drivers, but went with the MDR7506 40mm  instead and they arrived this morning for my little project.
  
 I am very keen however to get some more feed back on the 40mm carbons and especially the 50mm silk and wool driver  as i would also like to use this in another upgrade project for my sons gaming headset. (he's a bass head)
  
 Cheers.


----------



## nw130d

frank2908 said:


> Supprise, my new set of HD800 drivers arrived. Now I'm still unclear what to do next with them:
> 1 Create the same headphones so I can still enjoy them while sending one set to Tyll for measurement?
> 2 Create an open headphones? I doubt that I can make an open headphones better than stock
> *3 Going crazy: 2 drivers on one side, padless to compete with K1000???????*


 
  
 What's your reasoning with going 2x HD800 driver on each side (4 in total)? Or just for kicks?
  
 I would vote for sending your current set to Tyll to see how good a diy closed HD800 can be.
  
 AND go extremely crazy! Get yet another set of HD800 drivers... doing your 2x2 HD800-K1000 open


----------



## HiFiChris

nw130d said:


> I would vote for sending your current set to Tyll to see how good a diy closed HD800 can be.


 
  
 +1


----------



## kramer5150

WOW how did I miss this thread?  Incredible skills.
  
 I was just last night surfing Ali ... looking at those exact drivers!!
  
 I am a big fan of ear-speaker designs, the K1000 is one of my all time faves.  I just got an MDR PFRV1 the other week and am very pleased.  The imaging and soundstage are unreal for a "headphone".  They make my K701 sound like an etymotic ER4.
  
 If imaging and soundstage are what you are after, go for an earspeaker design.
  
 Good luck with whichever you chose!!


----------



## takato14

kramer5150 said:


> They make my K701 sound like an etymotic ER4.


 
 ... so the PFRs make your K701 sound better in every imaginable way?


----------



## wahsmoh

This looks like a more finished product than the McIntosh MHP-1000. If we go by looks alone it's hard to believe the McIntosh MHP-1000 costs $2000. He should pick up a new profession and start accumulating HD800 drivers for modification. The B&W Nautilus/HD800/MDR-Z7 looking super headphone


----------



## Priidik

knowhatimean said:


> Having just removed the actual grilles (a few days ago) I'm 99.999% certain that is what is causing the most resonance inside of the HD800 are those grilles resonating straight back to the metal ring you're looking at, as that ring is sitting over the edges of the grilles
> holding them down.


 
 Has the bass quantity remained the same?


----------



## frank2908

knowhatimean said:


> Having just removed the actual grilles (a few days ago) I'm 99.999% certain that is what is causing the most resonance inside of the HD800 are those grilles resonating straight back to the metal ring you're looking at, as that ring is sitting over the edges of the grilles
> holding them down.


 
 Are you referencing the grill and ring on the ear side of the driver? If so I' wondering how the driver would stay in place? The front of the driver has a removable drill and dust fabric, but if helps clamping down the driver.


----------



## Llloyd

Great thread.  I thought it was a different head fi user named frank and I was really surprised.  This makes a lot more sense.  Cool stuff.


----------



## coinmaster

We need more people voting for two drivers on each side 
	

	
	
		
		

		
		
	


	


_imagine the potential!_


----------



## takato14

coinmaster said:


> _imagine the potential!_


 
 you mean the potential for horrible acoustics and the most confused sounding headphone ever? yeah, that's exactly what I was imagining >___________>


----------



## coinmaster

takato14 said:


> you mean the potential for horrible acoustics and the most confused sounding headphone ever? yeah, that's exactly what I was imagining >___________>


 

 I'm thinking more like separate drivers to handle different frequency ranges resulting in clearer and better sound along with potentially larger sound stage.
 I think my imagination is cooler than yours


----------



## takato14

coinmaster said:


> takato14 said:
> 
> 
> > you mean the potential for horrible acoustics and the most confused sounding headphone ever? yeah, that's exactly what I was imagining >___________>
> ...


 
 I doubt he want's to design a crossover for that
  
 plus these drivers ain't cheap


----------



## coinmaster

Clearly he does or he wouldn't have asked  Unless he was actually going to just put two in and hope for the best.


----------



## kapanak

takato14 said:


> I doubt he want's to design a crossover for that
> 
> plus these drivers ain't cheap


 

 Well, he already has four of them XD


----------



## frank2908

kapanak said:


> Well, he already has four of them XD


 
 Well, the price for 4 drivers are less than the original hd800, plus you can have more fun, and possibly 2 different headphones
 To be honest I havent thought much about how to implement 2 drivers on one side, so take it lightly.
 Since making a pair of earpads is so hard, any one know any angled leather earpads that has a larger opening (especially the width) than the Audeze earpads?
 I want to try the Stax sr007, but read some where that the SR009 earpads has even larger opening. Can anyone post a picture of the sr009 earpads, side by side with the sr 007 would be splendid.
 The only problem is price, I've read somewhere that you can order the sr009 pads for $140?


----------



## mrscotchguy

frank2908 said:


> Well, the price for 4 drivers are less than the original hd800, plus you can have more fun, and possibly 2 different headphones
> To be honest I havent thought much about how to implement 2 drivers on one side, so take it lightly.
> Since making a pair of earpads is so hard, any one know any angled leather earpads that has a larger opening (especially the width) than the Audeze earpads?
> I want to try the Stax sr007, but read some where that the SR009 earpads has even larger opening. Can anyone post a picture of the sr009 earpads, side by side with the sr 007 would be splendid.
> The only problem is price, I've read somewhere that you can order the sr009 pads for $140?




Have you looked into the Angled pads from Lawton Audio? This might work, and they are real leather to boot.
http://www.lawtonaudio.com/fostexanglepads.html


----------



## agooh

Can you make mod for Audeze Headphones to lighten weight ?


----------



## frank2908

mrscotchguy said:


> Have you looked into the Angled pads from Lawton Audio? This might work, and they are real leather to boot.
> http://www.lawtonaudio.com/fostexanglepads.html



The opening of those lawton is not much wider than the audeze pads I'm using. Right now im looking at the stax sr009 and fostex th 600/900. Anyone have a spare set?
Im not making the mod for the audeze because Im a believer of wood.i doubt making the cups in 3d printed plastic would look and sound as nice.


----------



## takato14

agooh said:


> Can you make mod for Audeze Headphones to lighten weight ?


 Not feasible at all; most of the weight comes from the magnets, which are extremely powerful. Even if there was some way he COULD change the magnets without drastically altering the sound, disassembling the driver could be catastrophic. The magnets would likely rotate and snap together immediately after the bolts holding the plates together were removed, which would destroy the diaphragm and possibly even cause some of the magnets to shatter. Not to mention the potential for personal injury as a result of holding all of this in your hands as it happens.

Neodymium FTW.


----------



## frank2908

My first try on my own with carbon fiber, carbon fiber on a 3d printed old design baffle

 This is after a fresh spray of clear acrylic coat. I don't have a vacuum pump for vacuum bagging, so I afraid for small detail like "shell wave" on my 3d printed cup, the carbon fiber would not stick to the mould, anyway I will try to make the cup in carbon fiber soon.
 For this part, I did not have any access to a electronic weight scale, therefore the mixing ratio of epoxy and hardener is a little bit off. The result: it took one week and a half to cure 
 I know carbon fiber is not a good choice acoustically, but it look damn nice. I can use a bit of stiffness from them and add mass damping later. Hopefully the total weight would dive down. At the moment the headphones without cable weight 550 g. However this is due to the yoke made of stainless steel ( 2 of them weight 100g, the original aluminium alloy yoke from superlux weight 27g each)
 Any advice on carbon fiber are welcome here


----------



## doublea71

I met up with Frank today as we live in the same neighborhood and he was kind enough to let me borrow them for a few days (along with his Centrance Dacport) and I let him use my Mad Dogs 3.2s in return. I haven't listened to the HD800s enough to make a comparison, but on their own, these sound really really good. I think he must be pretty close to being finished with tuning these - the only things left to do are to improve the comfort and finish. The clamping force is a bit much for me and the Audeze pads aren't very forgiving. My initial impression is that they are very detailed without any noticeable harshness and sound very spacious for closed headphones. He's definitely on to something with these.


----------



## InsanityOne

doublea71 said:


> I met up with Frank today as we live in the same neighborhood and he was kind enough to let me borrow them for a few days (along with his Centrance Dacport) and I let him use my Mad Dogs 3.2s in return. I haven't listened to the HD800s enough to make a comparison, but on their own, these sound really really good. I think he must be pretty close to being finished with tuning these - the only things left to do are to improve the comfort and finish. The clamping force is a bit much for me and the Audeze pads aren't very forgiving. My initial impression is that they are very detailed without any noticeable harshness and sound very spacious for closed headphones. He's definitely on to something with these.


 
 Man for some first impressions that sounds pretty amazing! I can wait to see if a pair gets sent to Tyll for measurements!


----------



## doublea71

insanityone said:


> Man for some first impressions that sounds pretty amazing! I can wait to see if a pair gets sent to Tyll for measurements!


 

 The biggest issue right now is comfort. The clamping force is too much for me and that combined with the stiffness of the Audeze pads needs to be addressed. If he could get something more like Mr. Speakers Dog Pads, that would certainly help. I guess the clamping force can be fixed by bending the headband, but I'm not going to mess with it. He needs something under the headband, too. He said he used to have something to protect the head from the leather headband, but gave it to a friend. I think the one Philips uses on their X1/X2 looks pretty good - it's breathable and wide enough to distribute the weight evenly. If these things were in the ballpark of the HD800's level of comfort, I wouldn't care at all what they look like. If they were comfortable and had the polished, detailed look of Mr. Speaker's Alpha Dogs, Frank would do very brisk business if he chose to make them for sale. I let my wife try them with some music from an HDTracks sampler (Alexis Cole, Cassandra Wilson, Amber Rubarth - her kind of stuff) and she was very impressed, too.


----------



## InsanityOne

doublea71 said:


> The biggest issue right now is comfort. The clamping force is too much for me and that combined with the stiffness of the Audeze pads needs to be addressed. If he could get something more like Mr. Speakers Dog Pads, that would certainly help. I guess the clamping force can be fixed by bending the headband, but I'm not going to mess with it. He needs something under the headband, too. He said he used to have something to protect the head from the leather headband, but gave it to a friend. I think the one Philips uses on their X1/X2 looks pretty good - it's breathable and wide enough to distribute the weight evenly. If these things were in the ballpark of the HD800's level of comfort, I wouldn't care at all what they look like. If they were comfortable and had the polished, detailed look of Mr. Speaker's Alpha Dogs, Frank would do very brisk business if he chose to make them for sale. I let my wife try them with some music from an HDTracks sampler (Alexis Cole, Cassandra Wilson, Amber Rubarth - her kind of stuff) and she was very impressed, too.


 
 I see what you're saying. Even if these headphones were the best sounding closed-back headphones in the world, no-contest, I would still not buy them either if they had terrible comfort. But as you said, if the comfort is improved and looks refined just a tad, the headphones would be amazing. If they came to market I would absolutely pick up a pair regardless of the price.


----------



## doublea71

insanityone said:


> I see what you're saying. Even if these headphones were the best sounding closed-back headphones in the world, no-contest, I would still not buy them either if they had terrible comfort. But as you said, if the comfort is improved and looks refined just a tad, the headphones would be amazing. If they came to market I would absolutely pick up a pair regardless of the price.


 

 I have to mention that I'm not well-versed with TOTL headphones. I have heard the HD800s and LCD XCs, and some of the lesser Stax headphones, but these were at shows and just brief listens. I haven't owned anything better than my Mad Dogs and I'm equally inexperienced with top-end amps and dacs, so you have to take my impressions with a grain of salt, I suppose. I do think they sound excellent. A case in point: one of my favorite albums of all time, Beck's Sea Change, sounded better than I've ever heard it. His vocals were crystal clear and smooth at the same time, and that's what did it for me. I'm sure there are other headphones that will make Sea Change sound as good, but I now have first-hand experience that these cans do for sure, so I can't be anything other than highly impressed. Upping the comfort level is the first thing he needs to do imo. If their comfort matched the level of sound quality, I wouldn't care if they were Hello Kitty editions.


----------



## InsanityOne

doublea71 said:


> I have to mention that I'm not well-versed with TOTL headphones. I have heard the HD800s and LCD XCs, and some of the lesser Stax headphones, but these were at shows and just brief listens. I haven't owned anything better than my Mad Dogs and I'm equally inexperienced with top-end amps and dacs, so you have to take my impressions with a grain of salt, I suppose. I do think they sound excellent. A case in point: one of my favorite albums of all time, Beck's Sea Change, sounded better than I've ever heard it. His vocals were crystal clear and smooth at the same time, and that's what did it for me. I'm sure there are other headphones that will make Sea Change sound as good, but I now have first-hand experience that these cans do for sure, so I can't be anything other than highly impressed. Upping the comfort level is the first thing he needs to do imo. *If their comfort matched the level of sound quality, I wouldn't care if they were Hello Kitty editions.*


 
 I'm right there with you!


----------



## doublea71

doublea71 said:


> I have to mention that I'm not well-versed with TOTL headphones. I have heard the HD800s and LCD XCs, and some of the lesser Stax headphones, but these were at shows and just brief listens. I haven't owned anything better than my Mad Dogs and I'm equally inexperienced with top-end amps and dacs, so you have to take my impressions with a grain of salt, I suppose. I do think they sound excellent. A case in point: one of my favorite albums of all time, Beck's Sea Change, sounded better than I've ever heard it. His vocals were crystal clear and smooth at the same time, and that's what did it for me. I'm sure there are other headphones that will make Sea Change sound as good, but I now have first-hand experience that these cans do for sure, so I can't be anything other than highly impressed. Upping the comfort level is the first thing he needs to do imo. If their comfort matched the level of sound quality, I wouldn't care if they were Hello Kitty editions.


 

 I had to qualify my comments by mentioning my relative inexperience with all things high end because I don't want to start a hype train, the bane of every head-fier's existence.


----------



## frank2908

doublea71 said:


> If their comfort matched the level of sound quality, I wouldn't care if they were Hello Kitty editions.


 
 It's official, 100% head-fier want the headphones to be more comfy but dead ugly  Back to the drawing board.


----------



## doublea71

frank2908 said:


> It's official, 100% head-fier want the headphones to be more comfy but dead ugly  Back to the drawing board.


 

 I think making it more comfortable and better looking is probably a lot easier than making it sound good - the hard word is behind you imo.


----------



## InsanityOne

frank2908 said:


> It's official, 100% head-fier want the headphones to be more comfy but dead ugly  Back to the drawing board.


 
 Haha I think it would almost be hard to make them ugly at this point!
  
  


doublea71 said:


> I think making it more comfortable and better looking is probably a lot easier than making it sound good - the hard word is behind you imo.


 
 I agree with @doublea71. You have the hardest part(s) behind you and now you can just do the finishing tweaks for comfort and aesthetics. Although if you're a perfectionist like me the "finishing touches" will never truly be finished!


----------



## frank2908

Thanks guys. Now I'm going to build a new headband from scratch. I will make them from a single 5mm aluminium alloy solid rod ( similar to the bronze color aluminium slider on the T50rp), There will be leather strap and he-560 style gymbal.
 At this point I really want to have the Stax sr-009 pr fostex th-600 ear pads at hand to make a new baffle to push the driver even further forward, while increasing the comfort (hopefully)
  


doublea71 said:


> I think making it more comfortable and better looking is probably a lot easier than making it sound good - the hard word is behind you imo.


 
 Thanks Aaron, I hope you can find the time to bring it to the shop to A/B with the original HD800. If you do remember to bring the 1/4" adapter(plugged into the Dacport) so you can try their full sized amp.
 I auditioned them side by side for a short period of time, but very eager to see other's opinion about them


----------



## InsanityOne

frank2908 said:


> Thanks guys. Now I'm going to build a new headband from scratch. I will make them from a single 5mm aluminium alloy solid rod ( similar to the bronze color aluminium slider on the T50rp), There will be leather strap and he-560 style gymbal.
> At this point I really want to have the Stax sr-009 pr fostex th-600 ear pads at hand to make a new baffle to push the driver even further forward, while increasing the comfort (hopefully)


 
 Ooh, this is very exciting! I can wait to see pictures of the next version in the future! Good luck to you Frank!


----------



## IYAshike

Great work! l absolutely loved looking at the pictures and reading about the design/build process. Besides, l found your idea super interesting (i.e. HD-800 driver + closed-back design).
  
 Good luck for the coming upgrades!


----------



## frank2908

iyashike said:


> Great work! l absolutely loved looking at the pictures and reading about the design/build process. Besides, l found your idea super interesting (i.e. HD-800 driver + closed-back design).
> 
> Good luck for the coming upgrades!


 
 thank you
 at the moment Im quite busy with my own business, so it's on hold for a while
 Meanwhile I'm already contacted a fellow headfier to buy his used and modded stax sr007 earpads and fostex th900 ear pads. Hopefully, it will improve the comfort and look,while the larger opening means I can push the driver forward, to push the imageing of the mid further away ( deeper soundstage) 
 also I have already got some 2.5mm connector and this
 http://uk.farnell.com/schurter/4801-2200/socket-2-5mm-jack-panel-2pole/dp/143337
 My plan was to reduce the size of the connector to improve the look of these cans, however the Schurter connector do not provide enough "jack grip". The jack fall out easily, its really a shame because these connector are very well built and look good. So the conclusion is the Rean mini xlr will stay on the next version.
 As already described, the next version will be in carbon fiber. However I'm hessitating since I have 2 options:
 1 Improve the look of the previous design, replace 3d printed plastic with carbon fiber
 2 Implementing the theory from the designer of the B&w Nautilus reference:
 https://www.youtube.com/watch?v=0FKyfTsyYZI
 skips to  8:12 for the interesting bits

 the above image is the hd800 driver. See the 5 ported holes? My idea is instead of placing the driver inside a cup like most of the closed hp design, i'm making 5 plastic flexible tube (those used in compressed air components) to connect to those holes and close the tube at the end
 In theory there will be no way the sound can reflect back into the driver and also it would reduce driver and cup vibration
 However there will be helmholtz resonance presence, and the inside diameter and length of the tube will determine the frequency. The drawback is I have no experience calculating this, therefore lots of research is required. The good news is I can design each tube with different length, therefore there will be 5 resonance frequency, potential for active EQing, with less amplitude of resonance.
 The tubes will be directed into the headbands, gaining extra advantage of a smaller cup (there is hardly any) and lighter.
 Theory aside, atm I have no idea how to start, especially designing an adapter piece between the driver and tubes.


----------



## Bill-P

So, I finally got to meet Frank and discuss DIY. Also got to measure his headphone.
  
 Thanks, Frank! 
	

	
	
		
		

		
			




  
 Measurement data below. Note: measurements are meant to show *DIFFERENCES* rather than to definitively state whether something sounds "better" or more "neutral" than the others.
  
 Frequency response with Stax SR-007 ear pads: (with and without foam)
  

  
 Frequency response with Audeze ear pads: (with and without foam)
  

  
 Comparison between 2 different types of ear pads: (not subtle at all?)
  

  
 Frequency response of different pad types versus my modded HD600, which is my reference:
  
 Stax ear pads:
  

  
 Audeze ear pads:

  
 And versus a stock(ish) HD800 with Anax mod 2.0:
  
 Stax ear pads:
  

  
 Audeze ear pads:

  
*Subjective impressions:*
 I think Frank did an awesome job with his closed-back custom headphone based on the HD800. Subjectively, it actually sounds very close to one of the Stax headphones (tonally kinda similar to SR-009 with Audeze ear pads) rather than a dynamic. There was a slight lack of body and weight to the sound due to the lower level of bass, but for vocal music, it was awesome, which is much more than I can say for the stock HD800. I simply can't stand the HD800 at all. Anax mod makes it a bit more bearable, but still too piercing for my ears.
  
 This is definitely a colored headphone, or at least more so than my HD600, but... the sense of speed and overall presence is excellent! It's very very enjoyable, without any sense of fatigue. Soundstage is very open for a closed headphone (Stax ear pads, Audeze ear pads get close, but the sense of depth is not as good). HD600 is still a bit better in this regard to my ears, but it's quite surprising how "close" this headphone gets.
  
 So... kudos to Frank! Great job, man! I'm tempted to get some HD800 drivers to attempt some things myself, but I think I will hold back for now to give way for other projects. But hey, you've got something special going there!


----------



## frank2908

Thanks Bill for your visit and kind words
 For now, with the advantage of soundstage, I will use the stax pads for further tuning. The large opening of the pads allow more space, in the case of Audeze pads, some pad of the driver were covered by the pads. After the measurement session, I tried open 1 more 2mm diameter hole to tune down the mid a bit (as the graph shows the mid were quite colored). The result is the sound becomes a bit more open, treble increased a bit but not harsh. The mid actually damped down a bit, but obviously loose some of the lush sound.
 The session with Bill was to short. Next time I will ask him to measure the sound with tuning holes open/closed by small increment ( I made lots of small 1.5 and 2mm holes) to find the sweet spot.


----------



## c61746961

I've seen people use donuts made of open-cell foam sandwiched between the earpads and the baffle to lower 2-8 KHz energy successfully, you may want to look into the 'stratopads'.


----------



## frank2908

c61746961 said:


> I've seen people use donuts made of open-cell foam sandwiched between the earpads and the baffle to lower 2-8 KHz energy successfully, you may want to look into the 'stratopads'.


 
 I've already done that, since the measurement for each earpad with and w/o foam. Now I have to somehow reduce the 600hz-2khz range without affecting the "lush" midrange. It's quite a thin line


----------



## kapanak

Looking forward to more updates


----------



## coinmaster

Has anyone ever thought of using HD800 drivers for speakers? They sure do sound good when they come out of my headphones on full blast.


----------



## frank2908

kapanak said:


> Looking forward to more updates


 
 Sorry no photo updates yet.
 So far I have swapped the thick and uncomfortable Audeze pads for my modded stax sr007 pads. Not that the Audeze pads itself is uncomfy, but because my design had too much clamping force, and thick pads is pressed against your head.
 The sr007 pads is not sewn together, so I replaced the foam inside with my own piece of soft memory foam. It is now super comfy, and I had to add a piece of activated carbon foam disc between the pads and baffle to add more air and reduce the amount of mid.
  


coinmaster said:


> Has anyone ever thought of using HD800 drivers for speakers? They sure do sound good when they come out of my headphones on full blast.


 
 I dont think blasting the driver at high volume is a good idea. Plus the driver is 300 Ohm compare to normal 8 ohm speaker, so you need separate amp and a crossover.
  
 need help from you guys: I need to find the same white tape material used in the baffle of beyer dt headphones series and fostex th900. Many manufacturer used those "tape" to make the baffle lighter with lots of cutout and seal those cutout with tapes. I wonder if those white tape completely seal the baffle or they let certain air and frequencies through? Having holes and cutout in the baffle allow me to tune the mid and bass, but certain frequencies from the rear of the driver come out and interfere with sound, making humps in some frequencies
 Anyone own a sony R10 here? Mind you post some picture of the baffle and inside the cups?
 thanks
 Frank


----------



## IYAshike

Just to wrap up (help may come easier this way, l hope)...
  
*So you need:*
  
*1-* "_same white tape material used in the baffle of beyer dt headphones series and fostex th900_"
  
*2-* Some pictures of the baffle and inside the cups of a Sony R-10
  
 ....
  
 When it comes to me, my suggestion for your first 'need' is to write to Beyerdynamic (it may be easier than writing to Fostex due to language) and ask them to tell you about the white tape. They may even send you one (l guess as long as you pay for the shipping). lf you don't see yourself emailing them, ask me and l'll do it for you. l woulnd't mind to have the tape sent home and resend it to you, wherever you are (yes, l have to support your creative intentions )
  
 Maybe the day will come when someone will open up a Sony R-10 and will take pictures of the inside


----------



## frank2908

I have opened a superlux hd660 (beyer dt770 copy) and saw the similar tape. My guess is they filter the sound a bit but doest not seal totally. If my theory is correct, I can replicate with layers of micropore medical tapes. However I need more confirmation from others.
For r10 cups, I need more idea for creating a closed eadphones with big soundstage. I suspect have holes on the baffle for venting to the inside of the cup would solve this, however there is lots of reflection and resonance frequencies without proper design


----------



## IYAshike

Just trying to help...
  

  

  

  
 Amm... this one to... amm... lift up the spirits?


----------



## IYAshike

frank2908 said:


> I have opened a superlux hd660 (beyer dt770 copy) and saw the similar tape. My guess is they filter the sound a bit but doest not seal totally. If my theory is correct, I can replicate with layers of micropore medical tapes. However I need more confirmation from others.
> For r10 cups, I need more idea for creating a closed eadphones with big soundstage. I suspect have holes on the baffle for venting to the inside of the cup would solve this, however there is lots of reflection and resonance frequencies without proper design


 
  
 Look what l found! lt's better than nothing... Click here.


----------



## frank2908

after the first failed attempt at wood cup ( se 1st post) which thefinished quality is spectacular, the shape and sound was bad, I will try again
now Im working in Myanmar, which have a large supply of Paduak and Paduak Burl ( Amboyna burl), I will try to source some block to attemp cnc them.
Will post the design here. The shape will be an evolution of the 3d printed cup, since Am pretty happyand familar with the sound
Finger crossed


----------



## Makiah S

frank2908 said:


> As a long time head-fi follower of modding headphones, like many people here, I've tried 2 of the most popular headphones mod: the grado cup mod (in aluminium) and fostex T50RP (aluminium cup mod with Audeze/Kennerton earpads)
> 
> 
> Spoiler: Pics
> ...


 
 oooooooh that's gorgeous!!!!!!!!!!! Nicely done

 Excited to see what your results with the wood cup will b


----------



## catspaw

Did you just Butcher a 1.5k HP to experiment with its drivers?
 Now I know Im poor... .


----------



## c61746961

Earlier in the thread he made clear he ordered the drivers separately.


----------



## selwin

Just subscribed


----------



## catspaw

c61746961 said:


> Earlier in the thread he made clear he ordered the drivers separately.


 
 Hm... Guess thats what happens when you dont read everything carefully .


----------



## afganu008

Did you go forward with this, have you made any other modifications in this project?
 Thanks.


----------



## InsanityOne

afganu008 said:


> Did you go forward with this, have you made any other modifications in this project?
> Thanks.


 
 Yes, I am super curious about this as well! Such a neat project!
  
 - InsanityOne


----------



## frank2908

im designing new cup design, supposed to be in carbon fiber with 3d printed mould/tool. I dont have time yet to upload pics of the design. the recent prototype did not fit well together.


----------



## Kaszanas

I am honestly looking forward to see more of your work, as in some point of time I would love to try and do the same stuff.


----------



## frank2908

after a long time being away from this thread, but I have never stopped improving the design. The newest design takes me almost 5 months to fix some detail. The baffle would be made from 3d printed PLA Carbon fiber mix. THe cup & cup cover will be made from carbon fiber. I would 3d print the mould, then vacuum bagging them to produce the cup & cover. The cup ( with the ripple design) will be gloss, while the cover will be matt. I cannot render the cup in glossy CF, because you guys would not see the ripple effect.

 Carbon fiber 3d printed hd800 prototype- with cover removed

 Carbon fiber 3d printed hd800 prototype- drivers are more angled and moved further forward
  

 Carbon fiber 3d printed hd800 prototype- baffle & driver view

 Carbon fiber 3d printed hd800 prototype front side view

 Carbon fiber 3d printed hd800 prototype - rear side view
 I will use a Rean Tiny XLR connector


----------



## frank2908

Anyone here has any experience with moulding carbon fiber? I plan to use 3 layers for the cup (in blue) and cup cover (in carbon fiber render), expected thickness is 1-1.5mm, using 3k carbon fiber. Hopefully that would provide enough rigidity. The baffle supposed to be light and strong. I will add lightweight damping material such as Micropore, leather or alcantara. Will try to avoid Dynamat since it would anihilate my effort saving weight. My previous prototype weight around 500 gram. This potentially would weight as following:

18gr for baffle
16gr for carbon fiber cup
7gr for cup cover
2x Rean Tiny XLR connector.
40gr for HD800 driver
~100gr for headband assembly. However Im shaving the weight down using fostex t50rp headband and carbon fiber yoke
 Total should be less than 300gr.


----------



## rikk009

Wow...nice work!


----------



## frank2908

So far, I 3D printed the negative mould for the Carbon fiber cup
 On the first try, I applied the epoxy by hand using 3 layers of CF, but I used quick to dry epoxy ( dry time 10 mins), then vacuum bagging them. The resulting cup were too uneven and ugly to post
 Second try, I tried vaccum resin infusion. I mixed wrong ratio for epoxy and hardener, its been 1 wk and still not cured yet.Another issue is lots of air bubble. Reason is again quick drying time of epoxy, I cannot wait for 10 mins for all the air come to the surface and disappear from the mixing cup
 After total failure, I decided to 3d Printed the parts, then only cover them with 1 layer of carbon:

 3D printed headphones cup for HD800, note the flange for attaching the mini xlr connector

 3D printed headphones cup for HD800, for the cup in the bottom, due to the angle of printing, it looks really nice. For the cover, the top part is almost horizontal, you can see the line for the outer skin clearly

 3D printed headphones cup for HD800-side view

 3D printed headphones cup for HD800
 Unfortunately I was too unhappy with the carbon fiber parts to take any pic, Hopefully when I come back home after 2 months I can try again.
  

 My resin infusion kit
  

 Really messy table !!!


----------



## InsanityOne

Spoiler: Warning: Spoiler!






frank2908 said:


> So far, I 3D printed the negative mould for the Carbon fiber cup
> On the first try, I applied the epoxy by hand using 3 layers of CF, but I used quick to dry epoxy ( dry time 10 mins), then vacuum bagging them. The resulting cup were too uneven and ugly to post
> Second try, I tried vaccum resin infusion. I mixed wrong ratio for epoxy and hardener, its been 1 wk and still not cured yet.Another issue is lots of air bubble. Reason is again quick drying time of epoxy, I cannot wait for 10 mins for all the air come to the surface and disappear from the mixing cup
> After total failure, I decided to 3d Printed the parts, then only cover them with 1 layer of carbon:
> ...


 
  


 Personally I think that 3D-printed cup looks great! I never would have though to just 3D-print the cup and then cover it in carbon to achieve the desired look. I think the slight rough and very matte finish on the cup looks pretty sweet as well! Keep up the great work!
  
 - InsanityOne


----------



## frank2908

Just finished the design for the yoke. Pretty happy since it look a bit different from the popular hifiman or beyerdynamic or fostex yoke.

 3D printed assembly with new yoke design, front side view

 3D printed assembly with new yoke design, rear side view


----------



## frank2908

I got a PM asking for the guidance installing /fixing driver, but I thought posting here would be helpful to you all

 The driver is attached to the headphones from this side using 4 screws. SInce I don't own an origigal HD800, I wouldn't know which screw type, but I guess your best try is to buy a muiltiple screw set and try your luck. Another thing to consider is many people here (including me) have tried the SBAF french mod recommended by Tyll from Innerfidelity. The method requires cutting a central hole and easy to damage your driver. Another method ( with a correct screw driver needed) is to remove those 4 screw, and completely remove the lowerpart ( which contain the protector screen) since no wire is connected to them. This way it's non damaging and totally reversible.

 Last but not least, the wiring tap. Try to solder as quick as you can,sice the tap connected to a post surrounded by plastic. I had a bad experience soldering for too long and it melts the plastic and the voice coil wire disconnected from the post. After 2 days of crying (obviously TT ) I got enough bravery and open the bottom screen, solder the voice coil wire from the inside, and thank god it worked. 

  
 Good luck if you have to get into this situation
 Im sorry for not posting pictures of real driver , since I don't have them here with me
 Frank


----------



## Black Phoenix

props to you, Sir, for trying this


----------



## frank2908

Finally got a long holiday and had enough time to finish the new prototype.
 Unfortunately I could not make these out of carbon fiber, since I don't have enough time. Also last time I played with carbon fiber, turned out the epoxy I have hardened too fast ( 10 mins), therefore i can't do resin infusion or even normal lay up because of lack of time for air bubble to disappear.
 The earpads are mounted on plate with magnet attached, similarly there are magnets on baffle,
 Every parts are made from Carbon fiber High PLA filament from FIlabot
 weight: 400g without cable ( the last prototype weight 500g). Without dynamat, only weight 330g

 Old design, driver at a small angle, and remain in the center of the ear pad opening.
  

 New prototype driver mod

resonator made from 3d printed Brass PLA from colorfab, I can get the exact dimension , also the brass plastic is quite heavy, so it will damp the plastic protector. I had to take the driver apart and cut the screen off the center hole
  
  
the driver is at 35 degree from the baffle plate and push as much forward as possible
the baffle is lighter and has lots of opening. They are then covered with Micropore tape (white)
 
 Another view of the extreme angled driver.

  
 The backside of the baffle and the cups is covered in Dynamat, then one layer sound absorbing foam similar to Akasa Paxmate. The holes/ openings are covered with micropore tape.
 Mini XLR connectors.
  

  

  

  

  
 The Carbon FIber PLA is really stiff, strong and look really nice. It has a matt finish and looks really cool. On the left is carbon fiber PLA, right is normal PLA
  
 Finish


  

  
 3D printed HD800 in Carbon fiber PLA
 I was too lazy to make a new headband assembly from scratch, so I used an old Fostex T50rp headband.
  
 The connector will be covered in Black Sugru. I don't want to make a chunky and heavy 3d printed cover or housing for those connector. So it is kept simple.
 Sound improvement:
 Because the driver is much more forward and angled, the image of this can really improved. It is now very pin point. But there is still issues with lacking bass.


----------



## Thenewguy007

Any chance you plan on selling these DIY parts in the future?


----------



## SHAMuuu

Looks kinda like z1r cups


----------



## derbigpr

I worked on something very similar to this, trying to put a driver that is usually inside open headphones into a closed back one with custom made baffle and cup, very similar to what you have here. Inherently wrong for many reasons, one of the main ones is that drivers which work specifically in very opened headphones are made to work in very open enviroments, and when you put them inside a closed cup, you cut off all the bass, that's why you're experiencing that. Not only that, the front chamber, between the driver and the ear, has a lot of leaks into the outside on the HD800's through the stainless steel mesh and fabric earpads. On your headphones, there is no leakage to the outside from the front chamber, so you're messing up the way the driver works from back and the front. You can fill the cup with polyfill lightly to increase the effective volume of the cavity and maybe get a touch more bass, but you'll never get an ideal result. That's the first point. The second point is, because the driver is angled and the back of it is facing a wall that isn't flat, and the whole cup is not even in shape, you'll get a whole lot of resonances, reflections, whatever you want to call it inside the cup above 5khz or so, depending on the actual size of the cup, and each part of the driver membrane moves in an environment with a different acoustical impedance so to speak, it has to move a different amount of air, or work against different loads, and that creates imbalances on the membrane itself as it works.  The baffle openings that go directly into the back of the cup also don't work well if they're not properly balanced  around the driver. As soon as the airflow is not well balanced on all sides of the driver, you introduce all kinds of mess into the sound. To put it simply, putting an open back driver into a closed back design is pointless. Even if you somehow manage to get it to sound decent, it will never sound anywhere near as good as it does in an open back headphone.  That's why it's so damn hard to make closed back headphones sound good.  Even if you start with arguably the best dynamic driver in the world of headphones, you still have a tough time making them sound good.


----------



## Thenewguy007

derbigpr said:


> I worked on something very similar to this, trying to put a driver that is usually inside open headphones into a closed back one with custom made baffle and cup, very similar to what you have here. Inherently wrong for many reasons, one of the main ones is that drivers which work specifically in very opened headphones are made to work in very open enviroments, and when you put them inside a closed cup, you cut off all the bass, that's why you're experiencing that. Not only that, the front chamber, between the driver and the ear, has a lot of leaks into the outside on the HD800's through the stainless steel mesh and fabric earpads. On your headphones, there is no leakage to the outside from the front chamber, so you're messing up the way the driver works from back and the front. You can fill the cup with polyfill lightly to increase the effective volume of the cavity and maybe get a touch more bass, but you'll never get an ideal result. That's the first point. The second point is, because the driver is angled and the back of it is facing a wall that isn't flat, and the whole cup is not even in shape, you'll get a whole lot of resonances, reflections, whatever you want to call it inside the cup above 5khz or so, depending on the actual size of the cup, and each part of the driver membrane moves in an environment with a different acoustical impedance so to speak, it has to move a different amount of air, or work against different loads, and that creates imbalances on the membrane itself as it works.  The baffle openings that go directly into the back of the cup also don't work well if they're not properly balanced  around the driver. As soon as the airflow is not well balanced on all sides of the driver, you introduce all kinds of mess into the sound. To put it simply, putting an open back driver into a closed back design is pointless. Even if you somehow manage to get it to sound decent, it will never sound anywhere near as good as it does in an open back headphone.  That's why it's so damn hard to make closed back headphones sound good.  Even if you start with arguably the best dynamic driver in the world of headphones, you still have a tough time making them sound good.




Do you have any pics of your custom HD800?


----------



## frank2908

derbigpr said:


> I worked on something very similar to this, trying to put a driver that is usually inside open headphones into a closed back one with custom made baffle and cup, very similar to what you have here. Inherently wrong for many reasons, one of the main ones is that drivers which work specifically in very opened headphones are made to work in very open enviroments, and when you put them inside a closed cup, you cut off all the bass, that's why you're experiencing that. Not only that, the front chamber, between the driver and the ear, has a lot of leaks into the outside on the HD800's through the stainless steel mesh and fabric earpads. On your headphones, there is no leakage to the outside from the front chamber, so you're messing up the way the driver works from back and the front. You can fill the cup with polyfill lightly to increase the effective volume of the cavity and maybe get a touch more bass, but you'll never get an ideal result. That's the first point. The second point is, because the driver is angled and the back of it is facing a wall that isn't flat, and the whole cup is not even in shape, you'll get a whole lot of resonances, reflections, whatever you want to call it inside the cup above 5khz or so, depending on the actual size of the cup, and each part of the driver membrane moves in an environment with a different acoustical impedance so to speak, it has to move a different amount of air, or work against different loads, and that creates imbalances on the membrane itself as it works.  The baffle openings that go directly into the back of the cup also don't work well if they're not properly balanced  around the driver. As soon as the airflow is not well balanced on all sides of the driver, you introduce all kinds of mess into the sound. To put it simply, putting an open back driver into a closed back design is pointless. Even if you somehow manage to get it to sound decent, it will never sound anywhere near as good as it does in an open back headphone.  That's why it's so damn hard to make closed back headphones sound good.  Even if you start with arguably the best dynamic driver in the world of headphones, you still have a tough time making them sound good.



Thanks for your comment. Technically its hard. But since ive read about the sony r10, I know i had to try. Plus for a brand new hd800, I can get my 3d printer and the drivers and earpads, so i can make and play and enjoy even more. The fun part is the making and modding, not the sound anymore. And now i have made the headphones for my need, since I want to enjoy my headphones at work, so I bet mine would sound much better, has more bass than a hd800 in a noisy environment.
Frank


----------



## Maxx134

I have also noted that drivers designed to be more open don't do as well as drivers designed to be more closed and then opened lol.

Also have noted on closed versions of both the Fostex th 600, 
And the AudioTechnica esw10 use ports to their advantage and really help to open up the sound. 

I bet with a few tiny holes or channels in cup, 
 it would make a difference here as well.. 

I myself have an hd800 well modded in center driver and dynamat and tried most conceivable mods as well as changed sockets to mini xlr.. 

But the Sony R 10 has a really special midrange like some high end Audio Technica limited edition wood model I used to own. 
I had the luck and privilege to hear them at a friend's house and they have a really true mids and highs with lean tight bass. 


So this thread is really great to see and makes me think that Sennhieser dropped the ball,. By not making a closed version even if it needed to be ported like the Fostex th 900.


----------



## AudioCats

are HD800 drivers still available to the general public?


----------



## frank2908

yes they are. The headphones has ports, and i camouflaged them . Drilling holes reduce the cool factor i think.The ports located on the transition between the smooth surface and the ripple surface on the cup.
The hd800 driver stil available. You can find them on google.


----------



## RenZixx

Wow what an amazing idea, truly an amazing craftsmanship. Well I plan on doing these to my HD 25 (I have two with me) to see what the outcome is (just a project for poops and giggles). What do you think the outcome would be?


----------



## frank2908

It will be a lot of fun for you


----------



## leeperry

Considering the price of HD820 >_>


----------



## frank2908

Now that Sennheiser made the HD820 seems like the idea of closed HD800 is not crazy after all. Off course with the level of resource Sennheiser has for R&D its possible but why did they wait for so long?


----------



## RenZixx

derbigpr said:


> I worked on something very similar to this, trying to put a driver that is usually inside open headphones into a closed back one with custom made baffle and cup, very similar to what you have here. Inherently wrong for many reasons, one of the main ones is that drivers which work specifically in very opened headphones are made to work in very open enviroments, and when you put them inside a closed cup, you cut off all the bass, that's why you're experiencing that. Not only that, the front chamber, between the driver and the ear, has a lot of leaks into the outside on the HD800's through the stainless steel mesh and fabric earpads. On your headphones, there is no leakage to the outside from the front chamber, so you're messing up the way the driver works from back and the front. You can fill the cup with polyfill lightly to increase the effective volume of the cavity and maybe get a touch more bass, but you'll never get an ideal result. That's the first point. The second point is, because the driver is angled and the back of it is facing a wall that isn't flat, and the whole cup is not even in shape, you'll get a whole lot of resonances, reflections, whatever you want to call it inside the cup above 5khz or so, depending on the actual size of the cup, and each part of the driver membrane moves in an environment with a different acoustical impedance so to speak, it has to move a different amount of air, or work against different loads, and that creates imbalances on the membrane itself as it works.  The baffle openings that go directly into the back of the cup also don't work well if they're not properly balanced  around the driver. As soon as the airflow is not well balanced on all sides of the driver, you introduce all kinds of mess into the sound. To put it simply, putting an open back driver into a closed back design is pointless. Even if you somehow manage to get it to sound decent, it will never sound anywhere near as good as it does in an open back headphone.  That's why it's so damn hard to make closed back headphones sound good.  Even if you start with arguably the best dynamic driver in the world of headphones, you still have a tough time making them sound good.


Wont just making an angled pad fix that problem?


----------



## frank2908

My latest version, V4
I completed this last year actually but never posted since I traveled round the world for 1 year, so left this baby at home and just picked them up last month. I have a new design but my 3d printer broke and I'm on the road again,anw these sounds great with Chord Mojo





It's the first time I switch to open ear design, and there is a removable magnetic cap to convert to closed (not shown in photo). There is a dust screen cut off from stax sr007 earpads fabric. The driver cover is printed with honeycomb pattern








On the baffle and earpads rings there are magnets so I cant swap pads easily. Now I have the diy Stax pads (Sr007 with memory foam fill ) and Shure Alcantara earpads. The Stax produces a better soundstage and a bit more comfy because the memory foam I used is very soft, but if I'm not in a room with AC, then I switch to Alcantara pads. The alcantara has a bit smaller soundstage but better bass (tiny bit) 




The baffle is left open and sealed with 3M Micropore tape, which has the best balance between sealing (more base) and open (soundstage) IMO.
The original idea of making the headphones with huge closed cup like R10 and HD800 driver failed, not because of the cup but because the volume between the driver and the ear was not big enough, and the hd800 are designed for this huge volume. Now I plan for next build to be convertible between open/closed and over ear/ on ear. When you have an expensive headphones and a Chord MOjo, why do you have to buy another portable headphones? I believe to make a convertible portable hd800 would sound at least better than any $500 portable headphones anyway


----------



## RenZixx

frank2908 said:


> My latest version, V4
> I completed this last year actually but never posted since I traveled round the world for 1 year, so left this baby at home and just picked them up last month. I have a new design but my 3d printer broke and I'm on the road again,anw these sounds great with Chord Mojo
> 
> 
> ...


Man those look vintage, like Frankenstein made headphones. Have you tried different damping materials?


----------



## frank2908

I tried mostly before damping material at the back of the driver, havent tried much between driver and ear.
I like micropore, if only they are black, would look nicer. Maybe I should use a black marker pen and make them black.
This is the lightest headphones I made so far, around 300 gr.
I'm looking for a protective mesh on the driver side of the driver, something that would be acoustically transparent and block out all the dust. The aluminium mesh on the original HD800 is too coarse, as I might bring them out side of the house its not gonna stop dust getting in there.
Ideally the mesh covering the inside of the hd800 is great but I can't find something similar.Anyone have any idea?


----------



## RenZixx

frank2908 said:


> I tried mostly before damping material at the back of the driver, havent tried much between driver and ear.
> I like micropore, if only they are black, would look nicer. Maybe I should use a black marker pen and make them black.
> This is the lightest headphones I made so far, around 300 gr.
> I'm looking for a protective mesh on the driver side of the driver, something that would be acoustically transparent and block out all the dust. The aluminium mesh on the original HD800 is too coarse, as I might bring them out side of the house its not gonna stop dust getting in there.
> Ideally the mesh covering the inside of the hd800 is great but I can't find something similar.Anyone have any idea?


Have you tried natural felt? They seem to have amazing effects, try em!


----------



## frank2908

DIY bug got to me again, then I dropped the v4 and broke the single arm yoke ( pla is too brittle) so I make new version with the yoke connected on both side.
V5




The connector is switched from the heavy and bulky mini xlr to 3.5mm




The open surface on the baffe is covered with micropore and lined with liner material
Driver is angled at 10 degree.








I did not try the resonator mod yet, maybe next time.
The driver is attached by screw to the frame and yoke, the baffle and earpads are completely modular, attached by guiding screw and magnet, this way I can try different baffle design without making them all from scratch.








Another new improvement is the sliding rods are switched from 5mm aluminium to 3mm carbon fiber to reduce weight, the carbon fiber rods are more flexible, bending a bit to increase comfort. And I added mechanism to adjust the angle of the yoke, therefore I can adjust the clamping force by turning the screw.








Now to the sound:
First I left some plastic area of the baffle not covered in micropore, there was lots of reverb and reflection in the mid, completely cover all area reduce this, and adding the liner further reduce this effect. The soundstage is wide, imaging is good, but the singer voice appear to be not too much in front of my head, which Im not sure if the hd800 is supposed to do the same?
There is some small air gap between the baffle and the frame, therefore there is some bass leak. I will try to seal them with blutack or put some foam in between to seal them.
For the last 2 builds, the design is turning towards the open and large baffle volume of hd800 a bit. But last night I downloaded the manual for the sony r10 and has some design inspiration from them. Actually I tried the idea once but did not have enough material to play with.


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## frank2908

New version is very light, without cable 293 g, with connector is 306g


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## RenZixx (Oct 27, 2018)

Well try adding some dynamat. Every time I see those headphones I think of Frankenstein on steroids (which is really good).


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## frank2908

I'm trying to make them lightweight to increase comfort. Also I dont have access to dynamat atm. But making them lightweight and regid would reduce energy stored, therefore less vibration. The question is: is this regid enough.
The debate is similar to the turntable world, rega vs heavy turntable vs suspended turntable.
The sony r10 cup and driver and baffle is connected almost in 1 piece, then suspended from the frame, earpads by 3 screw and rubber damper, this is something I would like to try next


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## RenZixx

Dynamat = less vibration.
I would suggest CNC carbon fibre, its rigid AF and light as ever. So use a slightly thicker carbon layer and small pieces of dynamat.


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## Maxx134 (Oct 30, 2018)

RenZixx said:


> Dynamat = less vibration


There are two areas I pinpointed that are a concern for the driver vibration onto the frame.
 I have addressed this in my mod thread (linked in my sig)
It not only on both sides, but on the plane of angle of the frame that it extends outward to.
This all but eliminated the 6k ringing and then also the diffused pattern nature of the metal basket, which I see here has been replaced...
Regardless damping will benifit here but the downside is the nature of the dynamat material (messy if reversing)
Dynamat extreme is the only one I can recommend due to it having the most effect of these type materials..


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## RenZixx

Maxx134 said:


> There are two areas I pinpointed that are a concern for the driver vibration onto the frame.
> I have addressed this in my mod thread (linked in my sig)
> It not only on both sides, but on the plane of angle of the frame that it extends outward to.
> This all but eliminated the 6k ringing and then also the diffused pattern nature of the metal basket, which I see here has been replaced...
> ...


Agreed! Dynamat extreme is the best, sorbothane is also another option. I would combine the two for the best effect.


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## RenZixx (Oct 30, 2018)

Also another thing is that you can put dynamat on the headband (make sure its hidden) this should eliminate most of the ringing and transfer most of that energy into actual sound or bass rather then vibrating the headband. Mostly on the yokes tho.


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## frank2908

Another way to reduce vibration is to reduce the surface contact area between parts, similar to the pointy legs of speakers and turntables or damp them using rubber.
I have been studying the Sony r10 manual and design and they incorporate this idea. It can be divided into 2 main units:
  Wood cup, driver and wood baffle (where the driver is angled and has lots of holes on them) I believe those holes dont "breathe". They seems to be covered by paper tape with minimal breathablity, and they are there to reduce weight imo
   Frame, earpads and the yoke of the headband. This is oppose to most other headphones where the headband is linked to the cup or baffle, hence can transmit vibration from the driver or from the headband.
This 2 main units are joined by 3 screws and rubber ring, therefore isolate unwanted vibration. The wood part seems to be let vibrated according to their design, and the frame, earpads are isolated.


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## Maxx134 (Nov 4, 2018)

RenZixx said:


> Agreed! Dynamat extreme is the best, sorbothane is also another option. I would combine the two for the best effect.


In my testing, sorbothane worked best in either a slightly pressurized or slightly  tensioned position.
I have used it more successfully in the tensioned position of (around) a driver motor assembly, but the HD800 driver is a different animal completely and it is my opinion that the designers were very radical in their approach.


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## Maxx134

frank2908 said:


> Another way to reduce vibration is to reduce the surface contact area between parts, similar to the pointy legs of speakers and turntables or damp them using rubber.
> I have been studying the Sony r10 manual and design and they incorporate this idea. It can be divided into 2 main units:
> Wood cup, driver and wood baffle (where the driver is angled and has lots of holes on them) I believe those holes dont "breathe". They seems to be covered by paper tape with minimal breathablity, and they are there to reduce weight imo
> Frame, earpads and the yoke of the headband. This is oppose to most other headphones where the headband is linked to the cup or baffle, hence can transmit vibration from the driver or from the headband.
> This 2 main units are joined by 3 screws and rubber ring, therefore isolate unwanted vibration. The wood part seems to be let vibrated according to their design, and the frame, earpads are isolated.


This is very good to analyze the rear of the headphone designs.

In my analyzing the 800, 
the main issue I see wasn't the rear, but instead was that the driver was designed with intentions to propagate the soundfield outward from a distance, thus the "cage" it has.   

Any internal damping to the. Front "cage" & baffle area tends to effectively reduce the precious soundstage it was designed and famous for having.

I also seen this similar  approach in the Abyss phi.
I personally still think the Phi is larger in soundstage, but thats another topic.

So, Allowing sound wave to disperse naturally outward,  (like a speaker does in a room) actually helps in creating large soundstage.


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## frank2908

My current design uses the modded stax earpads , which has smaller opening than hd800 pads, and i also tried the shure alcantara pads. To my suprise the smaller alcantara doesnt sound that bad. The soundstage get a tiny bit smaller but you get a bit more bassand lower mids. This is the only mod that increase bass that doesnt mess up the mid and soundstage. As you said, any other damping in front of the driver would mess up the soundstage, and the smaller earpads is the least.


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## interface95 (Nov 9, 2018)

Wow, nice thread, just found it.
I'm going to do something similar with the hd700 drivers which don't sound so nice in their original housing.
But when they put it in the hd660, I thought they can't be too bad.
Arriving upcomming week, I'm interested how they will perform in my prototype 
I also would like to see some measures of your headphone


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## Maxx134

frank2908 said:


> My current design uses the modded stax earpads


Will the stax pads fit over the stock plastic from the original earpads?


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## frank2908

By original earpads you mean the hd800? No, just by the look of it i dont think so, they are totally different shapes


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## frank2908

To scratch my itch i got a new 3d printer and this is the progress of new version:
Double baffle design to increase the stiffness, even though printed in pla they are really rigid as 2 baffle plated attached by screw and brass knurled nut. Driver also attached to baffle this way. Its heavier than i expected but much stronger than previous designs ( thin plastic plus dynamat). Im printing the cup right now. This design is suppose to be smaller and semi closed.


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## frank2908 (Dec 17, 2018)

I've learn something new, the design game of the frame and enclosure is all about vibration (not just removing it, but to use them in a positive way, like using wood) and balancing the pressure between the front and rear of driver.
To use double baffle,the stiffness increased and there is less vibration I can hear.
To balance the pressure between front and rear, some manufacturer use vents on the baffle, however I found that backwave might affect the sound negatively, and as a result sound to bright.
I prefer the solution used in fostex or sony r10, basicly they use an earpads that offer good seal (pleather/leather) then adjusting the sound by vents on driver side using foam. It is in a way like using very thin velour earpads, then use leather earpads on top ( in a very simple explanation)
My design use huge gap between the double baffle and cover them in micropore tape.  By making the back side open or semi close, you change the pressure back side, then you have to adjust the pressure on the front side as well, thats why normally just making your originally closed headphones open (and vice versa)doesn't always sound nice.
I made new prototype in seashell oval shape.











I have added some damping on the 3d printed cup, and the gap between 2 baffle is 6mm, covered in micropore. Compare to my previous open prototype, on some tuning it offer rumbling bass but the mid is thick, and if I add more damping material, the treble really stand out and come alive without sounding harsh. But still thick mid annoys me. And the bass is a bit loose, and sound not too tight and fast, so I got my old wood cup out and back to the design board.
I present to you all the ultimate steampunk, with Iris door mechanism. I can transform between open to partially closed. The iris leafs were hand cut from brass, so the tolerance is very large, so it doesnt look very professional, but I dig it. Due to my bad skill, the iris can close maximum like in photo. The gap between 2 baffle is now 9mm and covered in micropore again. The wood cup is rosewood epoxy coated.













I dont put any foam or damping in the cup, because it will increase back pressure and IMO counter the point of making large ear cup. Without foam damping, the mid often sound too thick, thats why many people put foam damping. But you can solve it by reducing the pressure on the earside, making it further away from ear and let some air out by using porous tape (Micropore)
Now the vibration of the plastic cup is gone, sound very tight and clean. I like the most closed setting of the iris. Space and imaging is still there compare to the open (black ) version, but mid sound even tighter, treble surprise me the most. I can hear ever metallic "cling" and guitair metal strings sounds sooo sweet now. I did not expect that.
THe bass is quite expected, sound more punch and slam, and punchy, not even one bit punchy. It sound soo powerful and lots of energy now, but I have to get used to it for a while because the black open version sounded soft and laid back.
The drawback is only the look, now it is screwing huge!!! This is definitely something you enjoy holding in your hand and put on and enjoy music, not caring how you look like )


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## RenZixx

frank2908 said:


> I've learn something new, the design game of the frame and enclosure is all about vibration (not just removing it, but to use them in a positive way, like using wood) and balancing the pressure between the front and rear of driver.
> To use double baffle,the stiffness increased and there is less vibration I can hear.
> To balance the pressure between front and rear, some manufacturer use vents on the baffle, however I found that backwave might affect the sound negatively, and as a result sound to bright.
> I prefer the solution used in fostex or sony r10, basicly they use an earpads that offer good seal (pleather/leather) then adjusting the sound by vents on driver side using foam. It is in a way like using very thin velour earpads, then use leather earpads on top ( in a very simple explanation)
> ...


Why don't you make metal or aluminum parts from CNC machine's? They are much more capable when it comes to sound.


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## frank2908

My forst diy headphones (t50rp) had the cup made from aluminium. I didnt like the sound and they are not light enough. Im thinking next build would be carbom fiber bottom plate and top plate connected to driver from wood. Anyway the double baffle are connected by 8 screw and contact surface is very small ( brass knurled nut). It is similar to those turntable decks where the tables join each other by pointy legs ( or like loudspeaker legs) so vibration transfer should be minimal. And also im playing with what i have so for now thats all I can do.


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## RenZixx

frank2908 said:


> My forst diy headphones (t50rp) had the cup made from aluminium. I didnt like the sound and they are not light enough. Im thinking next build would be carbom fiber bottom plate and top plate connected to driver from wood. Anyway the double baffle are connected by 8 screw and contact surface is very small ( brass knurled nut). It is similar to those turntable decks where the tables join each other by pointy legs ( or like loudspeaker legs) so vibration transfer should be minimal. And also im playing with what i have so for now thats all I can do.


Well aluminum cups need certain thickness's to hit that sweet spot and they also need a ton of damping because aluminum do not absorb any of the backwave energy from the driver.

Carbon fibre is also an excellent choice but you will have to make them T H I C C, but check which carbon fibre you want to use. Remember no two materials are the same, every material need different dampings.


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## frank2908

Ok I agree damping is good to reduce vibration
But i prefer designs like the sony r10, where they apply vibration damping by attaching the wood cup ( which seems to me glued to wooden baffle) to the frame ( metal plate connected to earpads) by screws and rubber rings (insulators) 




In case of hd800, there is a rubber ring( a fellow headfi member send me a photo but I never own myself). 
On r10, there is no other damping required. So with proper mechanical damping and vibration isolation, you dont need tons of dynamat. On my wooden prototype, to take possible wood expansion due to weather into account and to damp vibration, I added 2mm foam strip on the contact area to the baffle ( they have 1mm gap). Things sounds great now.
What Im trying to say is vibration damping is a real issue, but headphones manufacturer tend not to use dynamat because there are other ways.
Now im trying to use stiff lightweight material and damp vibration at contact point. It looks more minimal and effective to me.


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## RenZixx

frank2908 said:


> Ok I agree damping is good to reduce vibration
> But i prefer designs like the sony r10, where they apply vibration damping by attaching the wood cup ( which seems to me glued to wooden baffle) to the frame ( metal plate connected to earpads) by screws and rubber rings (insulators)
> 
> 
> ...


Well I can't really argue with that! You may want to contact Lawton because he uses some special stuff to damp the Denon Dx000 line, he said its some super duper space station crap up in there (referring to the damping).


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## SHAMuuu

Bravo for effort sir. Bravo.


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## Reinhold

frank2908 said:


>


WOW, they look amazing. Great work


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## RenZixx

Are there any updates on those?


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## selwin

Nice work


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