# Stacking magnets?



## Slater (Feb 28, 2020)

I apologize if this has been discussed before. I searched & could not find anything on the topic, but there's no way I'm the first to think of it.

Has anyone ever tried stacking additional neodymium magnets (with opposite poles touching to effectively create a more powerful magnet) on the driver of their headphones? It would be a cheap, easy, and reversible mod to perform.

According to this site (http://www.kjmagnetics.com/blog.asp?p=doubled-forces), adding a 2nd, identically-sized neodymium magnet results in a magnetic force increase of ~169% (not 2x, due to the layers of plating on the magnets causing a slight reduction).

What effect does it have on sound? According to Fostex, higher magnetic flux density improves attack and decay for a crisper, more detailed sound signature. Headphones like the TH-X00 use magnets that exceed 1 tesla (1 tesla = 10,000 gauss).

Obviously, one would have to accommodate appropriately for drivers that have vent holes in the  magnet. And I know that manufacturers design the drivers and magnets to work together as one 'unit'. But that doesn't mean there aren't room for improvements. Cost certainly has a large influence on product design, and manufacturers usually don't just grossly overengineer everything. Why use 2x oversized magnets or plastic that's twice as thick/rigid when it can be engineered to be 'just good enough' but a whole lot cheaper?

==================================================

Update 01/22/2018 - Be sure to read through all of the posts in this thread possible, as lots of good discussion going on. As promised, I will be keeping this 1st post updated with a 'running database' of magnets that work on particular headphones. To have magnet/headphone data added to this post, follow the guidelines** below

1More MK801 - 20mm x 4mm round magnet (with hole)
Edifier H840 - 20mm x 5mm round magnet (with hole)
JVC HA-RX900 (placeholder)
Meizu HD50 - 15mm x 4mm round magnet (with hole). Stock driver is 15mm, & has (1) vent hole in center
Philips Fidelio X2/X2HR - 20mm x 5mm round magnet (with hole). Stock driver is 20mm, & has (1) vent hole in center
Philips SHL3300 - (placeholder)
Philips SHP9500 - 20mm x 7mm round magnet (with hole). Stock driver is 20mm, & has (1) vent hole in center
ISK MDH9000 - 20mm x 7mm round magnet (with hole). Stock driver is 20mm, & has (1) vent hole in center
Akai Project 50X - 20mm x 7mm round magnet (with hole). Stock driver is 20mm, & has (1) vent hole in center
Marantz MPH-2 - 20mm x 7mm round magnet (with hole). Stock driver is 20mm, & has (1) vent hole in center
LyxPro HAS-30 - 20mm x 7mm round magnet (with hole). Stock driver is 20mm, & has (1) vent hole in center
Freeboss MDH9000 - 20mm x 7mm round magnet (with hole). Stock driver is 20mm, & has (1) vent hole in center
Sivga SV007 - 20mm x 7mm round magnet (with hole). Stock driver is 20mm, & has (1) vent hole in center
Sony MDR-ZX100 (placeholder)
Sony MDR-ZX110 (placeholder)
SoundMAGIC HP150 (placeholder)
SoundMAGIC HP200 (placeholder)
Superlux HD-660 (placeholder)
Magnet mod is NOT possible on (at least) the following headphones:

1More H1707 Triple Driver over-ears
JBL J55
Sennheiser Momentum v1 (over ear)
Sennheiser HD 630VB
Philips A5 Pro

_*** Database Guidelines:*_

_You must specify the diameter of the stock magnet. If the stock magnet has 2 or 4 vent holes, include the largest diameter magnet that will fit 100% inside of the vent holes (ie without obstructing the vent holes)._
_You must specify the number and placement of the stock magnet vent holes (ie 1 vent in center, 4 vents in square pattern, 2 vents in straight line, etc)._
_Please provide the maximum size magnet possible (not just "whatever works"). For example, the Fidelio X2 will accommodate a *smaller* magnet, but 20mm*5mm magnets are the same diameter as stock (and thus the largest diameter/most powerful magnet possible)._
_Make sure you only list magnets that allow the cups to go back together without mods (it's not helpful to stack 6" of magnets on a driver if you can't put the headphones back together LOL)._
_PM me the information and I will add it to the database._


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## kkl10 (Jan 21, 2018)

Digging up this thread because this is related to something that interests me too and would like to see it discussed more often.

I did play around with little neodymium magnets (~5mm cubes and such), letting them stick to the back of some GMP 50mm drivers (the pull was quite strong) to hear for any differences. There was a very apparent effect in sound. The frequency response changed (less bass) and the overall sound seemed indeed somewhat crisper and cleaner. I think I noticed that the sound tended to become more BA-like with progressively more magnets (or a more powerful magnet) sticked to the back of the driver. Frequency response effect didn't go in the desired direction at the time (as I expected), and it seemed to have decreased lower bass extention (unexpected.. but I'm not at all versed in the physics of it all), but I can imagine how this might be an interesting method to try to tighten up the sound of sluggish/slow sounding headphones. Definitely something to play with when modding cheapo headphones.

I played around with this years ago and there were no ill-effects on the drivers whatsoever. They still work flawlessly today. But I don't know if it's safe with all dynamic drivers.

*EDIT: After testing a little more, I've realized that the FR and bass extension don't change at all. The sound simply becomes cleaner, clearer, faster.*


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## Slater (Jan 24, 2018)

Wow, I forgot all about this thread.

I run stacked magnets all of the time now (since I made this thread), and I have a selection of different "N" strengths, thicknesses, and diameters that I test out when modding headphones. As you discovered, it does have a noticeable effect on the sound.

They are so cheap to buy, it's easy to have a small collection of 4-5 different sizes on hand.

I exclusively use round magnets with holes in them, like this:




Using magnets with holes also guarantees compatibility with stock magnets that are solid, as well as stock magnets that already have a single vent hole in the center (like the stock driver magnet in this photo):



You have to make sure to center the 2nd magnet when placing it on top of the stock magnet, so the magnetic field matches the stock magnet's field. How to do this depends on the setup of the stock magnet. For stock magnets that already have a single hole in the center (like the photo above), it's easy because you can set the 2nd magnet on top of the stock magnet and line the imaginary 'center' of the holes up with one another. For drivers that have 2 or 4 small vent holes or drivers with no vent holes whatsoever, I mark the exact center of the stock magnet with a fine sharpie (a cross shape works best). I then 'center' the 2nd magnet on the stock magnet by using the hole in the center of the 2nd magnet to line up the sharpie marks through the hole like a cross hair. Make sense?

As far as the diameter of the 2nd magnet, I try to match the diameter of the stock magnet as close as possible (but slightly smaller is OK too). So if the stock magnet has a diameter of 20mm (and has no vent holes or a single vent hole), I might use a magnet of between 15mm and 20mm. If the stock driver magnet has (2) or (4) small vent holes in them (like these photos)...




...then I need to make sure to use a 2nd magnet that is smaller than the space between the 2 or 4 small holes. In other words, if the distance between the 2 of the holes (opposite to one another) is 15mm, I just make sure I get a magnet with a diameter less than that. The idea is that the 2nd magnet, once installed and centered on top of the stock magnet, fits inside of the small vent holes and doesn't block any of the vent holes.

_Update 01/24/18: Another user issued a reminder to make sure you orient the extra magnets the proper direction. If you attach them the wrong way, the sound can get WORSE not better. The details about how to install them the proper orientation is here: https://www.head-fi.org/threads/stacking-magnets.839878/page-3#post-13997758_


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## kkl10 (Jan 19, 2018)

Just grabbed some of those little neodymium cubes and they definitely make the driver more resolving. Imaging, more minute detail from blacker background, faster decay, etc,. This is with the drivers out of the headphone cups. I'm not so sure about the diminished bass response anymore... I'll have to hear for that latter again. My ears are not at their most perceptive right now...

The back of the drivers I have feature four vent holes as shown in your third picture. I always make sure to never cover any of those vents and try to more or less center the magnets in place, but I'm not sure that having the driver perfectly centered makes much of a difference...


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## Slater (Jan 19, 2018)

kkl10 said:


> The back of the drivers I have feature four vent holes as shown in your third picture. I always make sure to never cover any of those vents and try to more or less center the magnets in place, but I'm not sure that having the driver perfectly centered makes much of a difference...



I'm no physicist, but what you're trying to do when you center the 2nd magnet is to maintain an even magnetic field around the voice coil.

It's kind of similar to your wheels being balanced on your car. If you've ever driven with a wheel very out of balance, you'll agree that it's not fun to drive that way on the highway for instance. The stock magnet is perfectly centered for a reason. If it didn't matter, they would just slap the stock magnet on in any ol spot.

In other words, you are trying to enhance the stock magnet's magnetic field, not move it around or cause it to shift off-balance.



The little cubes are cool to play around with and see how the sound is affected, but for permanent modding you may want to consider get the proper disc magnets.

If the magnetic field is off balance (by just using random magnets that aren't centered), in theory there could be the possibility for driver distortion or stress on the fragile voice coil wire. At what frequencies and at what what volume that could occur, and if it would be detectable by casual listening, depends on the individual case.

BTW, you could test this by taking an old junk driver and some iron/steel filings. You'll be able to visually see exactly how the stock vs stacked magnetic field is affected with the different sizes and shapes of magnets (as well as their placement on the driver).


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## kkl10

Yes, thought of that. Seems like a plausible issue.

Have you by any chance found that magnets affected bass extension in some way?


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## Slater (Jan 24, 2018)

kkl10 said:


> Have you by any chance found that magnets affected bass extension in some way?



Not that I've noticed (at least, not during listening sessions).

Also, here's 2 photos I found of one of my early stacking mods. You can see the hole centering (the stock magnet had a single vent hole). The magnet used was a little small, but worked fine (it was just what I had on hand). I've since bought a number of different sizes of magnets to have on hand (they are only a few dollars for a bunch of them on Gearbest or Aliexpress).


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## kkl10 (Jan 21, 2018)

Just came across this interesting explanation of dynamic drivers by Tyll at innerfidelity. https://www.innerfidelity.com/content/how-headphone-dynamic-drivers-work

After playing around some more, I have to retract what I said about stacked magnets changing the FR. With the magnets I have, there's no such effect. Bass extension remains unchanged. There is simply a cleaner and faster sound.

I'm starting my modding efforts again, so I'll be getting stronger magnets than the N42 10 x 5mm neodymium disks I have now.

Would really love to see how this affects impulse response and THD in measurements. There has to be a significant effect. Somebody needs to give Tyll a shout about this.


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## Slater

kkl10 said:


> Just came across this interesting explanation of dynamic drivers by Tyll at innerfidelity. https://www.innerfidelity.com/content/how-headphone-dynamic-drivers-work
> 
> After playing around some more, I have to retract what I said about stacked magnets changing the FR. With the magnets I have, there's no such effect. Bass extension remains unchanged. *There is simply a cleaner and faster sound.*
> 
> ...



That is definitely what I have found (cleaner, faster sound especially with drums).

Unfortunately, I have no way to measure the differences. But I stack magnets on a number of my headphones, and so far to my ears it has always seemed to provide improvements. I certainly haven't experienced any negative effects yet.

It should also be noted that the magnetic field has to remain as close to the voice coil as possible. So I have never stacked any more than ONE magnet on top of the stock magnet. I believe stacking 2 or 3 extra magnets on top of the stock magnet might start moving the magnetic field away from the voice coil, or somehow having an unwanted or unpredictable effect. If the goal is to get a stronger field without stacking 2-3 magnets, you can always buy a larger diameter magnet, a thicker magnet, or a magnet with higher N rating.

When I order my 'selection' of modding magnets, I always order the highest N rating possible between magnets of the same diameter and thickness.


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## silverfishla

Slater said:


> That is definitely what I have found (cleaner, faster sound especially with drums).
> 
> 
> Unfortunately, I have no way to measure the differences. But I stack magnets on a number of my headphones, and so far to my ears it has always seemed to provide improvements. I certainly haven't experienced any negative effects yet.
> ...


Okay, you got me!  I’m curious.  Can you link the magnets that you bought on Ali?  So many magnets on there, it’s hard to choose.  It would help me if you could link to a trusted seller of magnets that you are satisfied with.  I’d like to try these with my pair of Sony Z7 which would seem to benefit from this mod.  I’ll post my results and give you all the credit!


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## Slater (Jan 21, 2018)

silverfishla said:


> Okay, you got me!  I’m curious.  Can you link the magnets that you bought on Ali?  So many magnets on there, it’s hard to choose.  It would help me if you could link to a trusted seller of magnets that you are satisfied with.  I’d like to try these with my pair of Sony Z7 which would seem to benefit from this mod.  I’ll post my results and give you all the credit!



It literally depends on YOUR magnet drivers, and any vent holes, all of which vary between headphones. There's literally no way for me to tell you what the best size magnets are for your Sony Z7s.

What you need to do is open your shells and measure your magnets, and whether or not they have any vent holes (and if so the distance between the vent holes). Then and only then can you go and search for magnets to mod with.

If you get that information and maybe take a few pics, I'll be happy to try and help you find some good magnets to use.

BTW, I also use the magnets with holes for all sorts of projects around the house. I screwed a bunch to a board that I hung on the wall and I use them to hang keys from when I walk in the house. I screwed some on my workbench to hold wrenches and other tools. I use them when making costumes and props for Halloween and comicons, to hold kitchen cabinet doors shut, to hold a bathroom door open when not in use, and even put them on my car's oil filter to catch metal particles before they damage my engine. They have a variety of uses, not just modding speaker drivers


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## kkl10 (Jan 21, 2018)

Slater said:


> It should also be noted that the magnetic field has to remain as close to the voice coil as possible. So I have never stacked any more than ONE magnet on top of the stock magnet. I believe stacking 2 or 3 extra magnets on top of the stock magnet might start moving the magnetic field away from the voice coil, or somehow having an unwanted or unpredictable effect. If the goal is to get a stronger field without stacking 2-3 magnets, you can always buy a larger diameter magnet, a thicker magnet, or a magnet with higher N rating.



Only way to find out is to experiment until something dies. I've been very liberal with my experiments and stacked up multiple neodymium magnets behind each driver. As far as I can perceive, there is no negative side effect to this and nothing suggests that the magnetic field around the voice coil might be shifting in position/orientation and/or losing its grip over the diaphragm. If things were going wrong in some way, I reckon that the effect would be very audible and obvious. On the contrary, the more magnets I add the more the sound cleans and clears up and becomes smoother. However, I've only explored this to a limited degree because I don't have that many magnets to really go crazy big (can get the column behind each driver up to ~5cm in height... looks silly but sounds even better ). There is also a point at which it's no longer worthwhile to add more height to the column of magnets behind the driver. A rod/column more or less three times as tall as it is wide might be enough for maximum gain in magnetic strength without redundant diminishing returns in sound quality. This could be impractical within many small headphone enclosures with relatively large drivers, though. On a truly open frame headphone, like mine currently is, it's very worthwhile to experiment.

Increasing the diameter of the additional magnets should provide a higher boost in magnetic strength than increasing the height. So it is indeed desirable to go for the largerst diameter and higher N grade to limit the column's height. In my drivers, there's an unfortunate limit of only ~13/14mm diameter because of the four vent holes on the back metal plate (currently using 10mm disk magnets).

I brought up Tyll's article because it's very educational about the anatomy of dynamic drivers in headphones. In my mind, this basic anatomy suggests that the effect of additional magnets tucked behind a headphone driver shouldn't affect the magnetic flux around the voice coil quite like you might be fearing. Take a look at the pics/illustrations on the article. It seems that the magnetic flux around the voice coil is guided by the metal pole pieces enclosing the permanent magnet of the speaker motor. There's one metal piece guiding the north pole of the magnet and another piece guiding the south. These pieces are static and independent from each other. One will always be the north and the other the south. Their arrangement seems to "shield" the voice coil from the direct effect of the magnetic field emanating from the permanent magnet itself. The points of strongest attraction of a magnet are its polar edges (correct?), and it's precisely these polar extremes that the metal plates guide to sandwich and trap the voice coil in place.

So placing the headphone driver (on its back) on the tip of an arbitrarily long rod magnet with similar diameter to the driver's north pole metal piece (as illustrated in some of the photos in Tyll's article, but maybe the exact diameter is not very relevant...) could shift the position of the whole magnetic field away from the voice coil. But since we only need the polar edges of the permanent magnet to trap the voice coil in place (and the polar edges of a magnet don't change when it comes together with other magnets) the magnetic field shift should not affect the speaker motor negatively. The added magnet should only contribute to increase even more the intensity of the magnetic flux at the polar edges around the voice coil, not to shift its orientation or position. Oh, now I see why it is indeed important to keep the axles aligned and centered. It's just like tucking two magnets together to form a larger one. The center of the magnetic field shifts to the center of the two magnets, but the magnetic flux at the polar edges intensifies.

Of course, I cannot exclude some sort of unpredictability in such a system. This is only my very limited understanding of the forces at play. In other words, I have no understanding of what I'm talking about and might have the wrong idea. Someone versed in the subject feel free to correct me...


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## Slater

Yeah, after reading Tyll's article, I have to agree with your thoughts. Everything you're saying makes sense.


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## FastAndClean

i just saw this thread and i put some magnets on my modded headphone for abusing and experiments (Hifiman HE350), there is a difference in the sound, they are a little bit faster for sure, i like the results


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## Slater

FastAndClean said:


> i just saw this thread and i put some magnets on my modded headphone for abusing and experiments (Hifiman HE350), there is a difference in the sound, they are a little bit faster for sure, i like the results



Nice, spread the word to this post!


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## Slater

silverfishla said:


> Okay, you got me!  I’m curious.  Can you link the magnets that you bought on Ali?  So many magnets on there, it’s hard to choose.  It would help me if you could link to a trusted seller of magnets that you are satisfied with.  I’d like to try these with my pair of Sony Z7 which would seem to benefit from this mod.  I’ll post my results and give you all the credit!



So I thought about this more, and while I can't guarantee a size that fits with the Sony Z7, I have found that a "safe" size of magnet that works for most drivers is the following:

For 40mm drivers, 12mmx4mm round neodymium N50 magnet with hole works for a lot of drivers.
For 50mm drivers, 15mmx5mm round neodymium N50 magnet with hole works for a lot of drivers.
Magnets are sold with different strengths - common ones you'll find are N35, N38, N50, and N52

I always get the N50 or N52 strength (which is the strongest gauss rating). If a seller or listing doesn't specifically list the N rating, I skip that seller.

I've got them from numerous sellers, and have never really had a problem. It's not like there's counterfeits. So I would say just get them from whomever you want. I've used Aliexpress, Gearbest, ebay, and Amazon in the past.

If you need to know what to search for on those sites, searching for something like "round neodymium magnets hole" is a surefire bet. Then look through the listings to find the size you need.

Depending on the size in the cup, you can get away with a larger or thicker size (for example, a 15mmx10mm). But be aware that often the thicker magnets are sometimes lower gauss, so you're not really gaining anything by getting a 15x10 N35 over a 15x5 N52. In that case, I would go with the more compact but stronger magnet.

The other advantage of sticking with the sizes I listed (12x4mm, 15x5mm) is that you can stack up 2 if you want, creating your own 15x10mm N52 for example. Note stacking 2 doesn't exactly double the gauss rating due to losses I mentioned in the very 1st post. Stacking up 2 will provide a 169% gauss increase, not a 200% increase (but it's still powerful as heck).

Again, the BEST solution would be to open up your headphone cups and measure the stock magnet to find out the biggest diameter magnet that will fit.

Hope that helps.


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## Cruelhand Luke

Have you noticed any pattern to how well a headphone responds to this mod in terms of type of cup configuration? To put it another way do you get better results with open headphones or closed?


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## Slater

Cruelhand Luke said:


> Have you noticed any pattern to how well a headphone responds to this mod in terms of type of cup configuration? To put it another way do you get better results with open headphones or closed?



I've done it on both open and closed. I've noticed no difference in results.


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## richard51 (Jan 22, 2018)

I stack 2 neodymium rectangular magnets n35 40x20x5mm on each cups, with blutak on the exterior  cups near the dynamic drivers but not directly on the driver, of my hybrid electro-acoustic and dynamic drivers Akg K 340, already modded, and I listen more clear bass , clearer sound and more definite bass, better voices... I will not dare to open it to place them at the interior though... The results are way desirable for me.... Thanks

I must added that my Akg are already modded with sorbothane for damping, agate+shungite,plastic grid mods, they were already TOTL, ,with the magnets now, I am short of words...I must add that a non modify AKG will perhaps be less affected than my already modified AKG, and my audio system is entirely treated against vibrations and the electrical grid of my house cleaned against EMI from the streetpost to the headphone,then my sensible system confirm what you said about these magnets... thanks very much indeed...

Update: definitely better, I listen to an indian cd of sarod and sitar,very difficult music to reproduce with the nuances and the nuances are way more there, without any negative impact at all....The tabla is more gorgeous...I had the impression that even_ the imaging is better_...AKG K 340 are top imaging headphones,modded they kill any of my upgrade urge, I dont even listen to my 2 Stax anymore.. Goddam! i am happy to have stumble upon this thread...

Update2: _Better integration of the 2 drivers_....I think so,because before these 2 magnets mods, my Akg heavily damped and treated did not present to my conscious mind this associated incoherency between the 2 drivers that many reviewers speak about...Now I begin to figure out what they speaks about.... Even with my mods pair without the magnets there was a little residual incoherency now very much corrected....I think so...Thanks really...


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## FastAndClean

now i am curios what will happen if i buy the strongest magnets on aliexpress and try them


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## Cruelhand Luke

I always have it in the back of my mind whenever I am trolling Headfi threads that I want to find ways to improve my Philips SHP9500s. I really like them, but all I have done to improve them is simply upgrade the pads. I haven't seen anyone crack them open and do any kind of damping inside the cup or mods to the back of the drivers yet. It seems like once they find the right pads, most people are pretty happy with their 9500s....or it's a stepping stone and instead of modding them further they go on to some X2, Beyerdynamics or Sennheisers.
Which brings me to my second thought. I think one of the many differences between a good headphone and a great one is in the amount of thought and attention to detail that goes into things like internal damping, proper filters, etc. 
I have never put too much thought into it, but perhaps one of the corners they choose to cut is in the size/strength of the magnets....
which means an easy way to improve the quality of the sound is by 'upgrading' the magnets strength?


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## Slater

FastAndClean said:


> now i am curios what will happen if i buy the strongest magnets on aliexpress and try them



Hopefully not this:


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## WaffleIron

Very cool thread. Bought some beefy 25mm x 20mm n52 magnets that I'll be chucking on some silk drivers with less than stellar magnets. I have a UMIK so I may be able to actually record the results.


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## Slater

WaffleIron said:


> Very cool thread. Bought some beefy 25mm x 20mm n52 magnets that I'll be chucking on some silk drivers with less than stellar magnets. I have a UMIK so I may be able to actually record the results.



That's a seriously beefy magnet! That's the size/strength I use on my car's oil filters.

One thing those interested in this mod should keep in mind is the final headphone weight when choosing magnets. On headphones such as the Philips A5 Pro I didn't do a magnet mod, because they are already quite heavy cans. So if your cans are already borderline, adding magnets that are really big might push them over the edge as far as comfort on the head. Some people are more sensitive to headphone weight than others.


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## WaffleIron

Slater said:


> That's a seriously beefy magnet! That's the size/strength I use on my car's oil filters.



Bigger is better, as they say in America.



Slater said:


> One thing those interested in this mod should keep in mind is the final headphone weight when choosing magnets



Yeah I was somewhat concerned about that. I ordered some smaller 20mm x 5mm magnets too just in case, but I'm not too worried.


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## Slater (Jan 22, 2018)

WaffleIron said:


> Bigger is better, as they say in America.
> 
> Yeah I was somewhat concerned about that. I ordered some smaller 20mm x 5mm magnets too just in case, but I'm not too worried.



20mmx5mm N50 (with hole) is what I usually get. They are plenty powerful for headphones from what I've seen.

For example, the 20mmx5mm size (with hole) fits absolutely perfectly on the Philips Fidelio X2 in case anyone is wondering. It made an already great headphone even better sounding.

And that also gives me an idea - I've updated the 1st post in this thread with a 'running database' of magnets that work with various headphones. I'd love the database to grow beyond just my own headphones, so follow the guidelines in the 1st post to have your magnet data added to the database.


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## kkl10 (Jan 22, 2018)

richard51 said:


> Update: definitely better, I listen to an indian cd of sarod and sitar,very difficult music to reproduce with the nuances and the nuances are way more there, without any negative impact at all....The tabla is more gorgeous...I had the impression that even_ the imaging is better_...AKG K 340 are top imaging headphones,modded they kill any of my upgrade urge, I dont even listen to my 2 Stax anymore.. Goddam! i am happy to have stumble upon this thread...
> 
> Update2: _Better integration of the 2 drivers_....I think so,because before these 2 magnets mods, my Akg heavily damped and treated did not present to my conscious mind this associated incoherency between the 2 drivers that many reviewers speak about...Now I begin to figure out what they speaks about.... Even in my mods,pair there was a little residual incoherency now very much corrected....I think so...Thanks really...



Better imaging, better coherence, better timbre, faster attack, better dynamics, blacker background, more transparency (you are there) are things that could be easily noticeable with particularly resolving headphones. I do notice these improvements with my GMP, especially if I stick stronger or more than 2 magnets per driver. In lower end headphones, there are other acoustic issues that might render these improvements unnoticeable or impossible.

Sticking a magnet directly on the back of the driver might also benefit the sound by virtue of the added weight, though. Less acoustic information is lost because the added inertia of the driver structure minimizes undue vibrations at the source. Mass loading not just the driver but the whole headphone brings big sonic benefits. As you probably know, doing it in a way that silences the structural ressonances of the headphones cups/structure also improves timbre. This is why wooden headphones tend to have better timbre. Wood ressonates much less than plastic or metal. I got my GMPs weighing almost 1 Kg... You get used to it .

Thanks for mentioning sorbothane. Never heard of it before. I had been using a type of sticky magnetic tape (stuff you put on fridge doors).



Cruelhand Luke said:


> I think one of the many differences between a good headphone and a great one is in the amount of thought and attention to detail that goes into things like internal damping, proper filters, etc.
> I have never put too much thought into it, but perhaps one of the corners they choose to cut is in the size/strength of the magnets....
> which means an easy way to improve the quality of the sound is by 'upgrading' the magnets strength?



Most industry insiders probably know about this magnet modding potential for ages and probably leverage it for commercial benefit because quality custom-made magnets can be quite expensive. Wouldn't make any sense that this hasn't been explored by anyone before.


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## richard51 (Jan 22, 2018)

Update3: I stack a 3th  magnet, 52n,(50x10x3mm) on top of the 2, 35n and guess what: little bit better on all counts....

Update4: more than a little bit better in fact....The Akg K 340 was almost perfect before that for me,now for me he is perfect....More body to the sound and at the same time more transparency....


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## Slater

kkl10 said:


> Better imaging, better coherence, better timbre, faster attack, better dynamics, blacker background, more transparency (you are there) are things that could be easily noticeable with particularly resolving headphones. I do notice these improvements with my GMP, especially if I stick stronger or more than 2 magnets per driver. In lower end headphones, there are other acoustic issues that might render these improvements unnoticeable or impossible.
> 
> Sticking a magnet directly on the back of the driver might also benefit the sound by virtue of the added weight, though. Less acoustic information is lost because the added inertia of the driver structure minimizes undue vibrations at the source. Mass loading not just the driver but the whole headphone brings big sonic benefits. As you probably know, doing it in a way that silences the structural ressonances of the headphones cups/structure also improves timbre. This is why wooden headphones tend to have better timbre. Wood ressonates much less than plastic or metal. I got my GMPs weighing almost 1 Kg... You get used to it .
> 
> ...



That's actually a really good point about the added weight to the driver. I've known people that swore by adding bluetac (or modeling clay, silly putty, etc) to the stock driver's magnet made improvements (I assume due to the added mass, dampening, reduction in vibrations, etc).


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## richard51

I can assure you that sorbothane works marvel....I damp my headphones and speakers with it.... Not only did he absorb vibrations but transform a part of them in heat... I use blutak only to glue something not for damping...


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## Cruelhand Luke

Slater said:


> That's actually a really good point about the added weight to the driver. I've known people that swore by adding bluetac (or modeling clay, silly putty, etc) to the stock driver's magnet made improvements (I assume due to the added mass, dampening, reduction in vibrations, etc).


I had thought about the mass acting as a damper as well. I am one of those people who swears by some putty around the driver on certain headphones (NVX SPT100 saw improvements...I'm told Boss Hifi B8 did not) but not all of them sit in the housing in such a way that there is anything to put the putty around...but the weight of the magnet might also reduce unwanted vibration. 
Reducing unwanted vibration seems to be an overlooked area on lower tier headphones and this could be a (small) step towards reigning in that kind of thing.


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## richard51

If you look at some thread where people give a photo of their stack of gear, you will discover visually the point I want to make now : almost nobody is conscious the way vibrations plague all system,even pro-reviewer, It is of the utmost importance to isolate, and damp all piece of gear, power strip,power conditioner,dac,amp,speakers,headphone....The second most important modification is cleaning the electrical grid where all the audio system is embedded, this fact is more,way more unappreciated than the other... These 2 ,cleaning and damping all elements and the grid is the key to top audio experience, without throwing tons of money....My experience and 2 cents....


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## kkl10 (Jan 22, 2018)

Slater said:


> That's actually a really good point about the added weight to the driver. I've known people that swore by adding bluetac (or modeling clay, silly putty, etc) to the stock driver's magnet made improvements (I assume due to the added mass, dampening, reduction in vibrations, etc).



Yes, same principle.

I did have blutak on the back of my drivers at the height of my modding efforts, however, it was mostly also just for gluing some tissue/felt disks behind driver (to cover the vent holes) to create a custom acoustic damping (it was earpad specific).

Don't think I heard much difference by virtue of the blu-tak weight alone. Might depend on the driver.... But to kill vibrations the material on the back of the driver should be relatively dense (heavy) and rigid, so magnets are much better in that regard.


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## kkl10 (Jan 22, 2018)

Slater said:


> And that also gives me an idea - I've updated the 1st post in this thread with a 'running database' of magnets that work with various headphones. I'd love the database to grow beyond just my own headphones, so follow the guidelines in the 1st post to have your magnet data added to the database.



Great idea.

For those headphone drivers that lack a vent hole at the center, I would advise to not overlook cone magnets like below. Matching the smallest base of the magnet with the back surface of the driver would yield even more magnetic boost without increasing the height. Specific dimensions would be headphone specific, I guess. I'll try to get a pair of these soon (25mm x 13mm x 10 mm height) + maybe a few 25mm disks for my GMPs but I'm not sure they would fit inside the stock cups.


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## Cruelhand Luke

richard51 said:


> I can assure you that sorbothane works marvel....I damp my headphones and speakers with it.... Not only did he absorb vibrations but transform a part of them in heat... I use blutak only to glue something not for damping...


Great, now I have to buy super powerful magnets AND sorbothane! Thanks guys for opening up TWO new rabbit holes in one sitting.
I don't know how much stray resonances the 'cups' on my Phillips 9500s are producing, but I think some sorbothane thoughtfully placed and 2 or 3 magnets on the back of the driver could possibly take them to the next level. I already have some pads I really like, I am skeptical of the price/performance ratio of 'upgradge' cables...but I have been thinking about doing something to treat the cups themselves.
I want HD650/Fidelio/DT880 type sound for the LEAST amount of money, which is why I got the 9500s in the first place. I have come to the conclusion that certain headphones have the potential to sound just as good as much more expensive headphones you just have to pay attention to the details that the manufacturer skipped, round off some of the corners they cut. I have a set of Fidelio L2s to compare the differences between well thought out, 'luxury' level headphones ....and _they already use _sorbothane or something very similar within the design of the headphone. I have been semi obsessed with the stuff for about a year now! I kept thinking, _THAT_ is the difference between my Fidelios and all my other budget/classic/vintage headphones...that attention to damping built into the housing. 
So...I'm glad to find a couple of mods (cheap and reversible ones!) that could help bring my 9500s closer to the level of my Fidelios....and maybe save me from buying another set of headphones for a while longer. I don't _need _another set of headphones, I just want to hear my music and movies as good as I can as cheaply as possible. The better I make the headphones I already have, the tighter the margin of diminishing returns becomes and the likelihood of me spending more money diminishes. It's economics!


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## richard51 (Jan 22, 2018)

buy sorbothane duro 70... self adhesive... the thickness of your choice relatively to the free space where you will put it.... the larger thickness is the better,but too much thick is not always possible in a small housing space.... remember to isolate the cups from one another, it is improvement also to put sorbothane between the 2 cups not only inside each cups....


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## Cruelhand Luke

richard51 said:


> buy sorbothane duro 70... self adhesive... the thickness of your choice relatively to the free space where you will put it.... the larger thickness is the better,but too much thick is not always possible in a small housing space.... remember to isolate the cups from one another, it is improvement also to put sorbothane between the 2 cups not only inside each cups....


thanks. I have been reading the 'stax-sorbothane' thread for _hours _now. 
I would encourage you to contribute to this thread:
https://www.head-fi.org/threads/the...l-your-full-sized-headphone-mods-here.867426/


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## kkl10 (Jan 25, 2018)

If your magnet can stick to the driver by two opposite sides (north and south pole), you might notice that one side exerts a stronger attraction than the other (the weakest might have an initial repelling effect that turns into attraction as it is brought closer to the metal). In my case, both sides stick and create very different sonic results. Joining the magnet to the driver by the strongest side benefits the sound as described before, but the weakest actually deteriorates sound quality. It makes my headphones sound underpowered and I think there's a big hit on frequency extension on both ends of the spectrum.

When magnets are forced together by the same pole they lose magnetism. Not what we want here. So always make sure to stack magnets on the drivers with the correct pole orientation (side that pulls the strongest).

Before getting a cone (or some other assymetrical shape) magnet, you may want to figure out which pole of the driver's permanent magnet is facing the back metal plate.


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## Slater (Jan 24, 2018)

kkl10 said:


> If your magnet can stick to the driver by two opposite sides (north and south pole), you might notice that one side exerts a stronger attraction than the other (the weakest might have an initial repelling effect that turns into attraction as it is brought closer to the metal). In my case, both sides stick and create very different sonic results. Joining the magnet to the driver by the strongest side benefits the sound as described before, but the weakest actually seems to deteriorate sound quality. It makes my headphones sound underpowered and I think there's a big hit on frequency extension on both ends of the spectrum.
> 
> When magnets are forced together by the same pole they lose magnetism. Not what we want here. So always make sure to stack magnets on the drivers with the correct pole orientation (side that pulls the strongest).
> 
> Before getting a cone (or some other assymetrical shape) magnet, you may want to figure out which pole of the driver's permanent magnet is facing the back metal plate.



Yeah, good point on that issue. Thanks for pointing this out. I'm sorry I didn't clarify that in my original mod.

It's very easy to distinguish when using the magnets with holes. The hole on 1 side of the magnet is chamfered (ie open wider like a funnel). This side goes UP when you attach the magnet to the driver. You must be more careful to get the correct pole orientation when using solid magnets (ie magnets without holes).

The correct way (when using a magnet with a chamfered hole) is just like this photo:



I have yet to find any headphone where it needed to be oriented the other way. Because of this, I believe all headphone drivers have their stock magnetic poles oriented the same way.

But exactly as you mentioned, when you stack the magnet the wrong way, it will briefly repel the extra magnet as you are coming closer to the driver magnet. This tells you that you're putting it on backwards.


----------



## Slater

I'll also add one final PSA to be aware of when searching for magnets.

Make sure you get axially-magnetized magnets. This means that one of the flat sides is N and the other flat side is S. Think of it like a coin, where the heads side is N and the tails side is S. *The vast majority of round disc magnets are axially-magnetized.*

But I mention this because there DOES exist diametrically-magnetized magnets (although they are rarer). These are like a pizza with half and half toppings - the half with mushrooms is N and the half with sausage is S. *You do not want this type of magnet.*

Here's a photo illustrating the difference (you want the one on the left):

 

Finally, here's a link with more information if you're interested in the differences, how to tell them apart if you are unsure of which type you have, etc: https://www.kjmagnetics.com/blog.asp?p=magnetization-direction


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## Cruelhand Luke

Slater said:


> I'll also add one final PSA to be aware of when searching for magnets.
> 
> Make sure you get axially-magnetized magnets. This means that one of the flat sides is N and the other flat side is S. Think of it like a coin, where the heads side is N and the tails side is S. *The vast majority of round disc magnets are axially-magnetized.*
> 
> ...


so I guess if I ever run across the fellas from the ICP I will refer them to you, because when they ask me, "magnets, how do they work?" I'll tell them @Slater  knows the answer.


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## Cruelhand Luke

I just ordered 10: 15mm rings and 20: 12mm rings both N52. from Gearbest...with the cost of shipping, minus some points I had the total was $10.00


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## Slater

Cruelhand Luke said:


> I just ordered 10: 15mm rings and 20: 12mm rings both N52. from Gearbest...with the cost of shipping, minus some points I had the total was $10.00



Nice! Let us know how it goes once they arrive and you are able to do some magnet modding!

I just finished up a modded Akai Project 50X tonight - converting it to open-backed (and adding a stacked magnet of course). You can kinda see the magnet right behind the grille:


----------



## Cruelhand Luke

Slater said:


> Nice! Let us know how it goes once they arrive and you are able to do some magnet modding!
> 
> I just finished up a modded Akai Project 50X tonight - converting it to open-backed (and adding a stacked magnet of course). You can kinda see the magnet right behind the grille:


I have an Akai 50X that will be getting the magnet treatment....how is it as an open back? I might be interested in doing that to mine.


----------



## Cruelhand Luke

Slater said:


> Nice! Let us know how it goes once they arrive and you are able to do some magnet modding!
> 
> I just finished up a modded Akai Project 50X tonight - converting it to open-backed (and adding a stacked magnet of course). You can kinda see the magnet right behind the grille:


also? I KNEW the 50X would look cool as an open back!


----------



## Slater

Cruelhand Luke said:


> I have an Akai 50X that will be getting the magnet treatment....how is it as an open back? I might be interested in doing that to mine.





Cruelhand Luke said:


> also? I KNEW the 50X would look cool as an open back!



It's awesome! Even better soundstage, much deeper sub bass extension, more sub bass quantity (or at least it seems to be more because of the deeper extension, so I think this is just an illusion).

I love it - the 50X/clones are great stock, but now it's even better. Plus as you mentioned it looks way cool.

The full writeups (along with some bonus mods) are here:

https://www.head-fi.org/threads/chi...-ear-headphones.822184/page-207#post-14097278
or
https://www.head-fi.org/threads/the...adphone-mods-here.867426/page-4#post-14097319


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## larry piencenaves

hi, new to this thread, just a noob question here, does magnets damages the drivers in the longer run?


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## Slater

larry piencenaves said:


> hi, new to this thread, just a noob question here, does magnets damages the drivers in the longer run?



No, all dynamic speakers have magnets in them already. It's a fundamental part of their design, and a dynamic speaker wouldn't work without a magnet.


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## larry piencenaves

Slater said:


> No, all dynamic speakers have magnets in them already. It's a fundamental part of their design, and a dynamic speaker wouldn't work without a magnet.



ahh i see thanks!. btw will this mod can be also applied to grados or takstar hi-2050?


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## Slater (Apr 7, 2018)

larry piencenaves said:


> ahh i see thanks!. btw will this mod can be also applied to grados or takstar hi-2050?



Any dynamic driver where it will phyically fit. That depeneds on the individual headphone. You can add a magnet to some headphones, but not others. Also, the size of the magnet needs to be taken into consideration.

There is more info here:

https://www.head-fi.org/threads/stacking-magnets.839878/#post-13985619
https://www.head-fi.org/threads/stacking-magnets.839878/#post-13985851


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## larry piencenaves

Slater said:


> Any dynamic driver where it will phyically fit. That depeneds on the individual headphone. You can add a magnet to some headphones, but not others. Also, the size of the magnet needs to be taken into consideration.
> 
> There is more info here:
> 
> ...




thanks, ill try to find those magnets at my local hardware shop


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## Cruelhand Luke




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## Slater

larry piencenaves said:


> thanks, ill try to find those magnets at my local hardware shop



Easiest is probably ebay or Aliexpress. You will need to measure your headphone and see what size magnet fits (or even IF a magnet fits), and if your headphone driver needs a hole in the magnet, etc.


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## Cruelhand Luke

larry piencenaves said:


> thanks, ill try to find those magnets at my local hardware shop


I ordered mine from Gearbest


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## Slater

Cruelhand Luke said:


> I ordered mine from Gearbest



Yeah, I forgot I got some from there too. Thanks for mentioning it!


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## larry piencenaves

I just found a magnet suitable for my needs, its a magnet from the driver on an a4tech headset that I bought for the sole purpose of using it as spare parts. is it ok to use this right? 
Its quite bigger in diameter compared to the width of the vents so it covers a bit the 2 vents on the grados drivers 


but I have to say this mod works man, instrument separation is better, minute details pops up even more and songs tempo is more correct and faster. and its aesthetically pleasing too. thanks slater


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## Slater

larry piencenaves said:


> I just found a magnet suitable for my needs, its a magnet from the driver on an a4tech headset that I bought for the sole purpose of using it as spare parts. is it ok to use this right?
> Its quite bigger in diameter compared to the width of the vents so it covers a bit the 2 vents on the grados drivers
> 
> 
> but I have to say this mod works man, instrument separation is better, minute details pops up even more and songs tempo is more correct and faster. and its aesthetically pleasing too. thanks slater



Looks great buddy!

Sure, wherever you can source a magnet is OK.

As far as covering the holes, it does change the tuning a bit. Those stock magnet vent holes control bass/sub bass. In general, when you cover up some or all of the holes (using anything from tape to bluetac to micropore/nylon filters to a magnet in your case), it usually reduces lower bass/sub-bass, and often boosts midrange.

Every headphone and driver is different however. I don't own any Grados (yet), so I don't know the exact effect on those vent holes. But as long as you like the end result, that's all that matters!

Nice job


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## Slater (May 3, 2018)

Also guys, it dawned on me that the stacked magnets is also serving the purpose of mass-loading the driver. The mass loading effect is likely a significant contributor to the differences we have all been hearing when stacking our magnets.

People usually mass load their drivers with materials like putty, clay, blue tac, dynamat, etc. But the magnets are *significantly* more dense and heavy (by volume), making it an ideal mass-loading material. It's like if you had a 1 cubic meter box you needed to make the heaviest mass possible - would you rather fill the volume with clay or steel? Hint: you wouldn't even be able to move the box of steel...

What percentage of the improvements is from mass loading vs the increased magnetic field is unknown. If I had to take a wild guess, I would say 60/40. Regardless, each incremental improvement is what matters, no matter where it comes from


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## Cruelhand Luke

Slater said:


> Also guys, it dawned on me that the stacked magnets is also serving the purpose of mass-loading the driver. The mass loading effect is likely a significant contributor to the differences we have all been hearing when stacking our magnets.
> 
> People usually mass load their drivers with materials like putty, clay, blue tac, dynamat, etc. But the magnets are *significantly* more dense and heavy (by volume), making it an ideal mass-loading material. It's like if you had a 1 cubic meter box you needed to make the heaviest mass possible - would you rather fill the volume with clay or steel? Hint: you wouldn't even be able to move the box of steel...
> 
> What percentage of the improvements is from mass loading vs the increased magnetic field is unknown. If I had to take a wild guess, I would say 60/40. Regardless, each incremental improvement is what matters, no matter where it comes from


I have been meaning to write more about this very thing. I think I talked a little bit about it in the 9500s thread. It seems to me that the effects that stacking a couple of thick little magnets on the drivers are threefold:
they add power to the magnet itself. (seems to increase clarity, instrument separation etc..it just makes them sound like better drivers)
they add a feeling of heft, the headphones are a little more stable on the head...it's a vague thing but they just feel more 'serious'
the added weight increases clamp, which in the case of the 9500s is a great thing. The drivers sound better closer to your ears... in stock form they are too far away, you lose a lot....anything that gets the driver close to your ear, without sacrificing comfort is a good thing....magnets are a nice little step.


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## skwoodwiva (May 4, 2018)

iso tried out this mod, krk woofer, Fluke 287, 3oz gel ball  dropped from fixed hight.  Etc etc
Pic lost when phone died. 
Results nadda.  3 x the magnet size w/ proper neos, or a 3 magnet set up with idenical krk magnets. 
Not a bit of peak recorded mv ac or dc noticed.  
It was like .3 v no matter what. ..

I abused the driver so much I need to reform the coil form , I bent it, @amn it.


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## skwoodwiva

Cruelhand Luke said:


>


Same but 3 on my sony cans
Sorry man it seems all head games. ..


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## Slater

skwoodwiva said:


> iso tried out this mod, krk woofer, Fluke 287, 3oz gel ball  dropped from fixed hight.  Etc etc
> Pic lost when phone died.
> Results nadda.  3 x the magnet size w/ proper neos, or a 3 magnet set up with idenical krk magnets.
> Not a bit of peak recorded mv ac or dc noticed.
> ...



So all you did was measure voltage, right? And there was no voltage change, so the mod doesn't work. Am I understanding this correctly?


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## Cruelhand Luke

Just because you didn't measure any change in the voltage doesn't mean the mod is useless. I tried it on 4 different headphones. I noticed differences in two of them and not so much in the other 2. 
The changes are pretty subtle and I think the main reason I was able to detect the difference in 2 of them is because those are the ones I have the most headtime with and listen to the most. I'm really familiar with how my 9500s reproduced sound without the additional magnets, and I do notice a difference. 
It's not a drastic mod that will knock your socks off, but it took them up a notch in terms of listening enjoyment. I don't find myself reaching for my Fidelio L2s nearly as much as I used to because I find myself leaving on the 9500s for more types of music. I feel like the mod brought the sq closer to my Fidelios and kind of shelved my Superlux HD681 because they aren't on the same level now. I used to like 681s for when I wanted a bright/spare/clean kind of sound with similar soundstage....they seemed more detailed than the 9500s, but that advantage is gone now, the 9500s are just BETTER in everything but the depth of the bass.
Now I need to get my hands on some sorbothane and see if I can get a little more bass out of my 9500s....


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## skwoodwiva

Cruelhand Luke said:


> Just because you didn't measure any change in the voltage doesn't mean the mod is useless. I tried it on 4 different headphones. I noticed differences in two of them and not so much in the other 2.
> The changes are pretty subtle and I think the main reason I was able to detect the difference in 2 of them is because those are the ones I have the most headtime with and listen to the most. I'm really familiar with how my 9500s reproduced sound without the additional magnets, and I do notice a difference.
> It's not a drastic mod that will knock your socks off, but it took them up a notch in terms of listening enjoyment. I don't find myself reaching for my Fidelio L2s nearly as much as I used to because I find myself leaving on the 9500s for more types of music. I feel like the mod brought the sq closer to my Fidelios and kind of shelved my Superlux HD681 because they aren't on the same level now. I used to like 681s for when I wanted a bright/spare/clean kexcursionuseriond of sound with similar soundstage....they seemed more detailed than the 9500s, but that advantage is gone now, the 9500s are just BETTER in everything but the depth of the bass.
> Now I need to get my hands on some sorbothane and see if I can get a little more bass out of my 9500s....


My two cents anyway.
Bass? The ball must have done  a very low excursion


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## Cruelhand Luke

skwoodwiva said:


> My two cents anyway.
> Bass? The ball must have done  a very low excursion


what does that even mean??


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## skwoodwiva

Cruelhand Luke said:


> what does that even mean??


If there were a flux density improvment then (at low freq)  then the ball drop would have indeed been in the sweet spot you refer to. 
Again just my take. ...


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## Cruelhand Luke

skwoodwiva said:


> If there were a flux density improvment then (at low freq)  then the ball drop would have indeed been in the sweet spot you refer to.
> Again just my take. ...


Yeah, I like speaking gibberish too, it's fun. Thanks for your two cents and hot takes.


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## Slater

Cruelhand Luke said:


> Yeah, I like speaking gibberish too, it's fun. Thanks for your two cents and hot takes.



haha, All Your Base Are Belong to Us!


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## rendyG (Aug 20, 2018)

My magnets finally arrived, GOSH they are strong!
I have trouble removing the original grill mesh, it is being attracted so much by the new magnet 
After a few minutes I really like the result, I feel everything tighter, more dynamic, possibly better attack 
I think the added weight of the magnets themselves contributes to the tighter bass a lot (mass loading).
Now I need to try this on my HD580 which I believe has similar sized magnets...

Thank you Slater!


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## ArgBoston

Just ordered a bunch of n52 magnets from aliexpress. I'm excited to test these on my X2's.


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## Geezer Rock 001

I have been following this thread and stacking seemed very logical to me. I contacted the maker of one of the Grado mod drivers that I use and asked about permanent adverse effects.  The answer was none. 

     I ordered a cheap $11 set of assorted magnets from Amazon. I put 11mm magnets on two different sets of drivers.  Initial thoughts are that they are more crisp and clear.

   A cheap and effective modification. Thanks for the idea.


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## kkl10 (Nov 9, 2018)

Another potential benefit, at least in theory, is that stacking magnets might turn headphones into slightly easier loads for amps... at least high-impedance headphones. By theoretically making the drivers work more efficiently, the bar for amping requirements/horse power is lowered.

Just speculation on my part. Proper measurements would have to be carried out to be sure.

But I'm not entirely sure of this because, on the other hand, the stronger the magnets stacked on my HP, the more I feel the need to increase the volume...

The sound improves yet I feel compelled to increase the volume dial on the amp... anyone else has experienced this?


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## Slater (Nov 9, 2018)

kkl10 said:


> Another potential benefit, at least in theory, is that stacking magnets might turn headphones into slightly easier loads for amps... at least high-impedance headphones. By theoretically making the drivers work more efficiently, the bar for amping requirements/horse power is lowered.
> 
> Just speculation on my part. Proper measurements would have to be carried out to be sure.
> 
> ...



I’ve only ever stacked 1 magnet, and never had a problem. However, I there is a point where it’s too much magnetic force and the driver can’t move.

You can test this by stacking a ridiculous amount of magnets. I’ve done this on open backed headphones back when I was 1st developing and testing this mod. Once you reach a certain point, the driver will struggle to overcome the magnetic force and will sound poor. It takes a lot of magnetic force though.

The real world limit for our purposes is the headphone cup itself. There is usually physically only room for 1-2 magnets. And this is perfectly fine; well within the limits of providing enough for positive results, but not so much that there’s negative results.


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## kkl10 (Nov 9, 2018)

Hmm, do you mean that in your experiments the drivers literally stopped working (made no sound or sounded distorted in some way) or they still reproduced sound but came off as extremely overdamped? How many magnets or how big/strong are you talking about exactly? Are you sure you didn't somehow block some vent or restrict airflow?

I can see it getting to the point of sounding overdamped, but I can't imagine it stopping working due to magnets...

In any case, this lowered volume effect I hear on my headphone already happens with the 1st magnet. Successive magnets add cumulatively to the effect. While I managed to go overkill to the point of making it sound somewhat overdamped, it never reached a point where it just stopped working. Instead, it reached a point where more magnets simply had no further effect.

I should mention that I don't necessarily think of this lowered volume effect as a problem. It's only a very slight difference and it could be a direct consequence of the fact that the sound is cleaner with less distortion or faster decay. I'm just wondering about the relationship between the effects of stacking magnets and amping requirements because I have reasons to believe that magnets can affect the impedance curve of a headphone..


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## Slater (Nov 9, 2018)

kkl10 said:


> Hmm, do you mean that in your experiments the drivers literally stopped working (made no sound or sounded distorted in some way) or they still reproduced sound but came off as extremely overdamped? How many magnets or how big/strong are you talking about exactly? Are you sure you didn't somehow block some vent or restrict airflow?
> 
> I can see it getting to the point of sounding overdamped, but I can't imagine it stopping working due to magnets...
> 
> ...



Overdampened, poor sound, etc. Sorry I didn’t clarify that above. I just edited my post to make it more clear.

And, no I didn’t cover anything up.

As far as how many magnets, I used big magnets not normally used for headphone drivers. They were like 75 or 100lb pull magnets.


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## kkl10

Slater said:


> They were like 75 or 100lb pull magnets.



How on hell did you separate those things apart...


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## Slater

kkl10 said:


> How on hell did you separate those things apart...



The trick is to slide magnets apart, not try and pull them apart.


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## Geezer Rock 001

Today I tried putting a double stack of 9 mm cheapo Amazon sourced magnets on a pair of lightly modded Grado SR 60e s. To my ears there was a marked improvement in their performance.  More crisp and faster.

Thanks Slater for starting this informative thread.

Question.  Is there a marked improvement with the more expensive magnets versus the cheap ones?


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## kkl10 (Nov 9, 2018)

Look for neodymium magnets with the highest N rating you can find (in principle, the stronger the better, but you can experiment with different N ratings to see if a lower strength works best). Magnets with the same size, shape and magnetic strength should have identical effect in the sound. Price is irrelevant. You might get more durable magnets from reputed suppliers, perhaps, which are a little more expensive. Just an issue of durability and reliability.

I pay a little premium to get most of my magnets from reputed European suppliers (some sell on Amazon) because I can trust their specs and because I have no patience to wait for ages. Haven't seen any Chinese seller that inspired much confidence in what they were selling, but that stuff costs almost nothing so...


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## Slater (Nov 10, 2018)

kkl10 said:


> Look for neodymium magnets with the highest N rating you can find (in principle, the stronger the better, but you can experiment with different N ratings to see if a lower strength works best). Magnets with the same size, shape and magnetic strength should have identical effect in the sound. Price is irrelevant. You might get more durable magnets from reputed suppliers, perhaps, which are a little more expensive. Just an issue of durability and reliability.
> 
> I pay a little premium to get most of my magnets from reputed European suppliers (some sell on Amazon) because I can trust their specs and because I have no patience to wait for ages. Haven't seen any Chinese seller that inspired much confidence in what they were selling, but that stuff costs almost nothing so...



Agreed.

I try to get N52 strength whenever possible. If not, then N50.

It’s also important to make sure you orient the magnet properly. In addition to perfectly centering it, you have to make sure the N and S poles are oriented correctly. You don’t want to put the magnet on ‘backwards’.


----------



## Geezer Rock 001

I was concerned about getting the pole orientation correct until I discovered that if you let the magnet "hover" over the driver, it will pop out of your fingers and align itself. They will even flip in mid air to get it right.

   I have tried this mod on five Grado type drivers and it has produced improved clarity and speed each time

   If you can safely get to your headphone drivers, this mod is easy, cheap and effective.


----------



## Geezer Rock 001

Slater, a question about magnet thickness. I have been using 1/32 N 52 cheapos  with very positive results. I have been looking at a magnet sales web site. My logic is to get the largest diameter N 52 that I can get, without covering the vent holes.

  My question is, do thicker magnets that have more pull force have a positive or negative influence? And when do you get to stacking over kill when it impedes the driver rather than helping it?


  Thanks for your expertise.


----------



## Slater (Nov 14, 2018)

In my experience and testing, a good rule of thumb is to try and match the diameter of the stock magnet (a little bit smaller is ok). And then I go with the thickest magnet that will physically fit in the shell, up to maybe 5-7mm thick.

As far as “too much”, as I mentioned a few posts ago, it takes ridiculous amount of magnetic force to get detrimental results. The amount of magnets it would take wouldn’t even fit in the driver cup! If you look at the very 1st post in this thread, I have a database of headphones I have tested, and the magnet sizes I’ve used in each (with nothing but positive results).

Even if you don’t have those exact headphones, you’ll still see somewhat of a ‘pattern’ from the list. There’s a fairly limited range of sizes that will fit most headphones (as 40mm and 50mm are the most common driver sizes).

For example, most headphones I’ve tried will accept a 15mm or 20mm diameter magnet, with a maximum thickness of 4mm-7mm. And I always try to get N52 or N50 strength if possible (weaker strength is still acceptable if N52 or N50 isn’t available).

Obviously you have to measure your exact headphone as YMMV (and some headphones can’t even have magnets due to space constraints). But the point is that there’s no monster 2” thick 75lb or 100lb pull magnets on that list, so there’s no need to even worry about “what if” this or that would be too powerful.

The only way I was able to get negative results was to take an open headphone, pop the rear grille out, and stack about 10 magnets. They stuck out the back of the headphone about 2”. It was ridiculous looking (like I had bull horns coming out of my headphones), and no one in their right mind would do that many magnets in real life. I just did it strictly as an experiment, to learn what difference there could be between 2 extremes (ie the difference between 0 and 10 magnets).

In the grand scheme of things, you really only need ONE magnet to get positive results (4mm-7mm for example), and that’s it.

I also want to emphasize that it is better to have 1 magnet vs multiple magnets. For example, on my Sivga SV007, the maximum size the cup will support is a 20mm diameter magnet of 7mm thickness. That’s ONE magnet. It would not be as effective to use (7) 1mm thick magnets stacked together, even though the end result would still be 7mm thick. There’s a magnetic loss every time you stack a magnet. Therefore, the single 7mm magnet will be much more powerful than the stack of (7) 1mm magnets (even though they both have the same overall physical dimensions).

I hope that helps! Let me know if you have any other questions


----------



## Geezer Rock 001

Thank you VERY much for the detailed explanation and I am sorry if I over looked it your previous explanation.


----------



## Slater

Geezer Rock 001 said:


> Thank you VERY much for the detailed explanation and I am sorry if I over looked it your previous explanation.



Anytime friend.


----------



## ArgBoston

I attached n52 magnets to my SV007s and I noticed the bass appeared to be tighter. I need to to do more tests but i definitely noticed a change.


----------



## Slater

ArgBoston said:


> I attached n52 magnets to my SV007s and I noticed the bass appeared to be tighter. I need to to do more tests but i definitely noticed a change.



Nice! I have a magnet to my SV007 as well!


----------



## mufflertape

Hey Slater I just wanted to say thanks for giving me the Idea to add magnets to my hd58x, I put a magnet with over 2 Tesla of surface gauss(cleanest sound) and it has worked out pretty good, Ive tried a magnet that weighs a little more and has about 700 gauss and both are good(cleaner than stock with more full bass than the stronger one). I would like someone to validate the testing but clearer highs less mid bass and better sub bass rumble were are present. I can answer any questions as well etc.


----------



## Slater

mufflertape said:


> Hey Slater I just wanted to say thanks for giving me the Idea to add magnets to my hd58x, I put a magnet with over 2 Tesla of surface gauss(cleanest sound) and it has worked out pretty good, Ive tried a magnet that weighs a little more and has about 700 gauss and both are good(cleaner than stock with more full bass than the stronger one). I would like someone to validate the testing but clearer highs less mid bass and better sub bass rumble were are present. I can answer any questions as well etc.



Glad you like it!


----------



## mufflertape

Slater said:


> Glad you like it!


Yes sir! Also here are some measurements I took, It doesn't measure bass below say 100hz but still useful to prove the sonic difference. They will be linked as stock, then large ring magnet, then smaller very strong magnet. Also for references I use mine with dekoni velour pads as well as testing with my blue snowball mic in case someone wants to compensate the graphs.
Stock:
https://cdn.discordapp.com/attachments/163118487559077888/517900753235607553/unknown.png

Large Ring Magnet:
https://cdn.discordapp.com/attachments/163118487559077888/517903403725094922/unknown.png

Dense 2+ Tesla Ring Magnet
https://cdn.discordapp.com/attachments/163118487559077888/517900180847198247/unknown.png

Also I can link to the specific ones I bought as well, Just let me know everyone.


----------



## ArgBoston

ArgBoston said:


> I attached n52 magnets to my SV007s and I noticed the bass appeared to be tighter. I need to to do more tests but i definitely noticed a change.


Added a second magnet on each side. The first thing I noticed is that the treble is definitely less fatiguing. This was the first time I was able to use these headphones all day without needing to take them off because of the treble spike.


----------



## Slater

ArgBoston said:


> Added a second magnet on each side. The first thing I noticed is that the treble is definitely less fatiguing. This was the first time I was able to use these headphones all day without needing to take them off because of the treble spike.



Nice! What are the size dimensions of the magnets are you using? Diameter and thickness...


----------



## ArgBoston

Slater said:


> Nice! What are the size dimensions of the magnets are you using? Diameter and thickness...



20 x 4


----------



## legopart

How to do such mod on HD650 ?
on top of the plastic?


----------



## mufflertape

legopart said:


> How to do such mod on HD650 ?
> on top of the plastic?


I dont think you can, it is part of the overall driver, I mean if your not worried about breaking them or if anyone has done a tear down video then go for it, I don't think it is possible to do this mod to them so that is why I haven't done it. I am Sorry


----------



## rendyG

legopart said:


> How to do such mod on HD650 ?
> on top of the plastic?



You'd need to remove the spider cage which is holding the little piece of foam. (irreversible mod)
Google "hd650 spider cage", you will find a lot of pics with exposed magnet.
I want to do this mod on my hd580, but didn't have time yet..


----------



## legopart (Dec 9, 2018)

rendyG said:


> You'd need to remove the spider cage which is holding the little piece of foam. (irreversible mod)
> Google "hd650 spider cage", you will find a lot of pics with exposed magnet.
> I want to do this mod on my hd580, but didn't have time yet..



After I cut the spiders the original magnet felled out so I glue i, really scarring mod... the sound improved with this mod.
it having vary strong magnet inside with giant hole, my magnet hole is smaller.
still I will try it with or without the magnets

this is HD6XX
only 2 can get inside (and for fun I put 5 out side cause the 2 inside push and touching the case  )




inside beyerdynamic Dt880 I put 3 inside, I felt big improvement !

for HD6XX is better without, in my opinion, but with the mod without the covers is better (but using glue is so dangerous)
so or the stack magnet is stronger enough or it just not effected!


----------



## rendyG

legopart said:


> After I cut the spiders the original magnet felled out so I glue i, really scarring mod... the sound improved with this mod.
> it having vary strong magnet inside with giant hole, my magnet hole is smaller.
> still I will try it with or without the magnets
> 
> ...



Your picture looks really funny 
I thought the magnets in hd650 were attached securely.. You are right that using glue near the driver is dangerous.

Magnets with smaller diameter of the hole should be ok, but this driver type is really sensitive to how much air you let through this hole. More air = bigger and looser bass.


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## Slater

legopart said:


> How to do such mod on HD650 ?
> on top of the plastic?



What is under the foam in the very center?


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## legopart (Dec 9, 2018)

Slater said:


> What is under the foam in the very center?


something like this




but without the spider on the HD6XX the magnet is falling out easily (on the top of this magnet has some metal plate) and you will see the coil on the other side.
the diameter is bigger then reholar magnet hole

I cover this hole with some material that covered some beyerdynamic dt880 driver





one of the bad mods ever to cut this spider out of this speaker.
If this magnet fall when the coil under vantage  it will burn it out.


----------



## Slater

legopart said:


> something like this
> 
> 
> 
> ...



If the only way to get to the magnet is to cut off the spider, but cutting off the spider risks damaging the magnet, then I would leave that model alone and I would not stack any magnets. It’s not worth the risk to destroy the driver.

I have a hunger of headphones that can’t have any magnets added to them, because there is either no room or the driver is in a sealed mini enclosure (Sennheiser HD630VB and Sennheiser Momentum).

That’s just the way the cookie crumbles sometimes, and I accept it.

That’s the thing with the magnet stacking mod - it can’t be done on every headphone. So it looks like the HD6XX is one of those headphones that can’t have the mod at all.

Unless there’s something I’m missing.

Should I add the HD6XX to my list in the 1st post of this thread, and indicate that the HD6XX can’t be modded? And what about the HD600 and HD650? Do they look exactly the same as the HD6XX (with the spider piece)? Because if so, I will add them to the list also.


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## legopart (Dec 9, 2018)

HD6XX is the same one drivers as HD650, but the plastic parts made in china.
- Its really possible that the magnet on all models hold with this spider and not glued!
- The polarity of this magnet twice stronger then any neodymium magnet that you can put on it.
- there is not any effect or positive effect from additional magnets.

also HD580, HD600, HD 650, HD660, HD6XX, (not HD58X)
Built on the same structure, engendering and idea
*BUT* my HD6XX is first hand!, new ones.

It's really great mod that helps to lot of vintage headphones that built with less stronger magnet or one that waked  after years,
I put 3  round magnets on old Beyerdynamic DT990 Driver (the same engineering like DT990 and DT880 pro/edition (exept the 80ohm and DT770 that covered on the back) )
3 flat on top, 3flat on the bottom of Echo n16 isodynamic, still not like it but fill improve
broke 1 flat to half for AKG K141 (constroction of the headphones almost the same for all AKG models ), the driver magnet having 4 hols (tries not to cover it). there great improve.
*some one told hear about AKG K340 (I will check letter)

Beyerdynamic Dt100 cant improve, some spider covering the magnet hole + not much space to put additional magnet inside the cans


flat one: N35 30 x 10 x 2 *not understood the different when bough 3 years ago
round: N50 15mm x 5mm with hole (another bought with data --> BR:14000-14500 GAUSS)


----------



## Slater

Excellent, thanks for the explanation friend


----------



## Sharpty

By adding a magnet in the direction that it is attracted to the speaker, you are actually pulling field lines away from the center of the yolk. If anything this will decrease sensitivity and decrease voice coil control. People are saying it is an improvement most likely because the sharpness of the highs are getting rolled off. Because of the design of a speaker magnet, the only way to increase the field across the yoke is to use a bucking magnet, in the repelling direction, that will constrain and redirect the driver's field lines towards the voice coil. This used to be done for magnetic shielding on speakers so they wouldn't damage CRTs, but it also slightly increases sensitivity and voice coil control.


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## Slater (Dec 21, 2018)

Sharpty said:


> By adding a magnet in the direction that it is attracted to the speaker, you are actually pulling field lines away from the center of the yolk. If anything this will decrease sensitivity and decrease voice coil control. People are saying it is an improvement most likely because the sharpness of the highs are getting rolled off. Because of the design of a speaker magnet, the only way to increase the field across the yoke is to use a bucking magnet, in the repelling direction, that will constrain and redirect the driver's field lines towards the voice coil. This used to be done for magnetic shielding on speakers so they wouldn't damage CRTs, but it also slightly increases sensitivity and voice coil control.



Don’t knock it till you’ve tried it.


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## Sharpty (Dec 22, 2018)

Slater said:


> So, I take it you’ve tried the magnet stacking mod for yourself and are speaking from experience?



Experience in physics, a decent understanding of electromagnetics, and a decent understanding of speaker design. If anyone wants to do some measurements, that would be great.

If you think about the shape of a speaker magnet its basically a 360 degree horseshoe magnet. You're just sticking a magnet in the middle of that horseshoe magnet. That will not increase the field strength between the ends of the horseshoe

https://electronics.stackexchange.c...r-magnet-to-the-back-of-the-speaker-magnet-do

https://www.diyaudio.com/forums/full-range/96407-changing-fr125s-bucking-magnets.html

http://www.htguide.com/forum/showthread.php?42901-Introducing-the-SSA-WG&p=605789&viewfull=1#post605789


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## Slater (Dec 21, 2018)

Sharpty said:


> Experience in physics, a decent understanding of electromagnetics, and a decent understanding of speaker design. If anyone wants to do some measurements, that would be great.
> 
> If you think about the shape of a speaker magnet its basically a 360 degree horseshoe magnet. You're just sticking a magnet in the middle of that horseshoe magnet. That will not increase the field strength between the ends of the horseshoe
> 
> ...



So you are speaking from an armchair position, and have not actually performed the experiment for yourself in real life.

There’s nothing wrong with theory, knowledge, hypothesis, etc. And that’s great that you have knowledge of physics and whatnot. But at some point a scientist has to test their theory in real life.

Because read through this thread. There’s a whole lot of people that have actually done this mod. In real life. With actual results. On multiple headphones.


----------



## legopart

There Is another problem.
1- Each magnet covered by metal plate (from front and behind), That stop almost all the observation of the magnetic force
2- Old headphones use very weak magnet, such as Ferrite and covered by a metal plate, so you cant really feel the different between the magnet sides. 

maybe we need some needle compass to check the right polarity of things?






For example this one from Chinese
Its includes the azimuth too  for shipping coordinates 
https://www.ebay.com/itm/40mm-Clear...=item4423ba2c68:g:M~UAAOSw3vFbWsZL:rk:10:pf:0


----------



## Sharpty

Slater said:


> So you are speaking from an armchair position, and have not actually performed the experiment for yourself in real life.
> 
> There’s nothing wrong with theory, knowledge, hypothesis, etc. And that’s great that you have knowledge of physics and whatnot. But at some point a scientist has to test their theory in real life.
> 
> Because read through this thread. There’s a whole lot of people that have actually done this mod. In real life. With actual results. On multiple headphones.



I never questioned whether or not people did it in real life and that it made some difference, but how much is placebo and real is an endless rabbit hole. I've read thru this thread and found no measurements or actual scientific understanding to back this up. You guys have subjective conjecture, I tried to find measurements to back it up.  Don't take it personally. What one person thinks is an improvement, might actually be a decrease in real measured performance.

Why not try the magnets reversed and let us know how it sounds


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## Sharpty (Dec 21, 2018)

legopart said:


> There Is another problem.
> 1- Each magnet covered by metal plate (from front and behind), That stop almost all the observation of the magnetic force
> 2- Old headphones use very weak magnet, such as Ferrite and covered by a metal plate, so you cant really feel the different between the magnet sides.
> 
> ...



Ferrite magnets don't equate to weaker drivers, it just takes a smaller magnet when neodymium is used. Maybe someone can find some cans with alnico magnets but I doubt it


----------



## rendyG

Sharpty said:


> I never questioned whether or not people did it in real life and that it made some difference, but how much is placebo and real is an endless rabbit hole. I've read thru this thread and found no measurements or actual scientific understanding to back this up. You guys have subjective conjecture, I tried to find measurements to back it up.  Don't take it personally. What one person thinks is an improvement, might actually be a decrease in real measured performance.
> 
> Why not try the magnets reversed and let us know how it sounds



I did the measurements, some graphs are in shp9500 thread (on cheap diy rig). Subjectively I felt the upgrade on shp's.. 
I haven't skipped physics at university and I don't uderstand where are you heading with the horseshoe magnet. Circular magnets have completely different mag. field around them, dont they? And everyone can try that placing two magnets on each other will result in atronger magnetic field...


----------



## Slater (Dec 21, 2018)

Sharpty said:


> I never questioned whether or not people did it in real life and that it made some difference, but how much is placebo and real is an endless rabbit hole. I've read thru this thread and found no measurements or actual scientific understanding to back this up. You guys have subjective conjecture, I tried to find measurements to back it up.  Don't take it personally. What one person thinks is an improvement, might actually be a decrease in real measured performance.
> 
> Why not try the magnets reversed and let us know how it sounds



Sometimes all you have to go by is subjective observations.

I don’t need a mass spectrometer reading to tell me that wine/beer/bourbon A tastes better than wine/beer/bourbon B. There will be a scientific explanation for it (such as trace amounts of sulfur or some other impurities). But at the end of the day I use my taste buds and make a subjective determination. Does that mean my taste buds are wrong because I don’t have a gaggle of graphs and scientific data to back up my subjective opinion? Nope; we live in an imperfect world. And I’m OK with that.

Heck, scientists don’t even know exactly how the brain works, or how some medications function, despite decades of scientific data, scans, tests, and measurements. That doesn’t mean they don’t work though.

There’s absolutely nothing wrong with hard science, data, graphs, etc. But at the end of the day, what I care about most is how my headphones sound to me. I can’t hear a graph or a pie chart. I can hear music.

Don’t get me wrong; I’m not against quantitative data or scientific scrutiny. If you want to buy gauss meters and other equipment to take measurements for proving or disproving your theory, we all welcome it as it will benefit the community. I’m not going to, but if someone wants to buy me the equipment I’ll be happy to take all the measurements you want.

Finally, it’s entirely possible that some or all of the improvements we are seeing could simply due to mass loading the driver. It may have nothing to do with magnetic fields. Modders have been mass loading their drivers with positive gains for a long time, with everything from clay to bluetac. It’s possible the magnets are just doing the same thing.


----------



## Sharpty (Dec 21, 2018)

rendyG said:


> I did the measurements, some graphs are in shp9500 thread (on cheap diy rig). Subjectively I felt the upgrade on shp's..
> I haven't skipped physics at university and I don't uderstand where are you heading with the horseshoe magnet. Circular magnets have completely different mag. field around them, dont they? And everyone can try that placing two magnets on each other will result in atronger magnetic field...




Yes placing two magnets of the same orientation together increases the strength, but you are not taking into account how the field is shaped by the center pole aka the yoke.

you have a flat washer shaped magnet, the top is S and the bottom is N, the yoke is attached to the N or bottom and it becomes an extension of the magnet, which directs the N field lines up thru the middle of the voice coil. If you look at a speaker from the side and cut the magnet in half, you have two side by side U magnets with the center being N and the outside being S. Thats why I say a 360 degree horseshoe.

This pic shows the yoke, cap, and magnet as one piece but you can see the polarity of the system which is the important part. It helps to try to visualize the field lines. It would be much easier to demonstrate this I think

yes the poles are reverse of what i wrote



So when you add a magnet to the back of the speaker in the attracted direction, you actually pull some field lines away from the yoke. If you add a magnet in the repelling orientation, you force those field lines away from the rear and back into the yoke


----------



## Sharpty (Dec 21, 2018)

Slater said:


> Finally, it’s entirely possible that some or all of the improvements we are seeing could simply due to mass loading the driver. It may have nothing to do with magnetic fields. Modders have been mass loading their drivers with positive gains for a long time, with everything from clay to bluetac. It’s possible the magnets are just doing the same thing.



The added mass must have some effect. Someone replied earlier saying the treble was less fatiguing after the mod, which makes me think it could be from a decrease in resolution from a slightly weaker field across the VC. But alas it is all hearsay. I'll try it both ways when I get the chance


(Forgive me father for I have double posted)


----------



## Slater

Sharpty said:


> The added mass must have some effect. Someone replied earlier saying the treble was less fatiguing after the mod, which makes me think it could be from a decrease in resolution from a slightly weaker field across the VC. But alas it is all hearsay. I'll try it both ways when I get the chance



Agreed. It’s possible all the magnetic fields and whatnot are just a red herring.

It could just be that a hunk of mass on the back of the driver is what’s helping more than anything.

Many modders load the backs of their headphone drivers with anything and everything - modeling clay, silly putty, bluetac, dynamat, etc.


----------



## Sharpty (Dec 21, 2018)

Slater said:


> Agreed. It’s possible all the magnetic fields and whatnot are just a red herring.
> 
> It could just be that a hunk of mass on the back of the driver is what’s helping more than anything.
> 
> Many modders load the backs of their headphone drivers with anything and everything - modeling clay, silly putty, bluetac, dynamat, etc.



Just ordered a mass loading kit for my Senny HD25 actually 

Greetings from Cinci btw haha


----------



## Slater

Sharpty said:


> Just ordered a mass loading kit for my Senny HD25 actually
> 
> Greetings from Cinci btw haha



Nice!

Represent the 513

Did you go to the Ohio CanJam in October 2017? It was a great time, and loads of nice gear (stock, modded, vintage, high end, etc). Jude and friends brought some awesome stuff.


----------



## Sharpty

Slater said:


> Nice!
> 
> Represent the 513
> 
> Did you go to the Ohio CanJam in October 2017? It was a great time, and loads of nice gear (stock, modded, vintage, high end, etc). Jude and friends brought some awesome stuff.



Nope I did not. I used to be more interested in headphones about 7-8 years ago, just recently been getting into it again. I'll have to find out when the next one is.


----------



## rendyG

Sharpty said:


> Yes placing two magnets of the same orientation together increases the strength, but you are not taking into account how the field is shaped by the center pole aka the yoke.
> 
> you have a flat washer shaped magnet, the top is S and the bottom is N, the yoke is attached to the N or bottom and it becomes an extension of the magnet, which directs the N field lines up thru the middle of the voice coil. If you look at a speaker from the side and cut the magnet in half, you have two side by side U magnets with the center being N and the outside being S. Thats why I say a 360 degree horseshoe.
> 
> ...


Nice explanation, but the headphones that I´ve seen always had a magnet with a hole in the middle, similar to this one:
https://www.aliexpress.com/item/5Pc...agnetic-20x3mm-with-Hole-5mm/32847767211.html
So adding second magnet to the back shlouldn´t hurt the field imho


----------



## Sharpty (Dec 21, 2018)

rendyG said:


> Nice explanation, but the headphones that I´ve seen always had a magnet with a hole in the middle, similar to this one:
> https://www.aliexpress.com/item/5Pc...agnetic-20x3mm-with-Hole-5mm/32847767211.html
> So adding second magnet to the back shlouldn´t hurt the field imho



It doesn't really matter if there's a hole or not, that only slightly changes the field shape of an axially polarized magnet. You still have a pole on each flat side.



Your setup is like the magnet on the right half. Its best to visualize the internal speaker magnet, yoke, and cap (orange parts) as a single magnet since the yoke and cap are highly ferrous. This means the end poles of the magnet are on the inside and outside of the VC, and the backplate of the speaker magnet has a field orientation somewhere in between N and S (S dominant in this pic) because it has now become essentially the middle of the magnet. Since you are adding a magnet in the attracted orientation you are attracting field lines from the middle/south pole of the speaker magnet towards your external magnet. I don't know how to better explain this without a simulation or demo. You can find more info if you search something like "bucking magnet speaker"
There has been lots of research into this topic from the days of CRTs, hard to find anything recent though.


----------



## legopart

The magnet is pushed or polled by the both sides same polarity that affect the coil.
The middle part may be hollow, and the speaker will still work fine






You know what, vise versa, only the center will got the polarity





on ideal roll, this position wont work at all, the magnetize coil wont move anywhere.


----------



## Sharpty (Dec 21, 2018)

Also by adding magnets that are stronger than the speaker magnet itself, you can significantly weaken the field across the VC. Bucking magnets are usually 60-80% as powerful as the driver magnet to keep from overpowering it and weakening the flux at the VC gap


----------



## legopart

Do the old school magnets become weaker ?


----------



## Sharpty

legopart said:


> Do the old school magnets become weaker ?


Magnets do lose strength over time but it is very slow under normal conditions. Heat and impact will weaken a magnet


----------



## legopart

Sharpty said:


> Also by adding magnets that are stronger than the speaker magnet itself, you can significantly weaken the field across the VC. Bucking magnets are usually 60-80% as powerful as the driver magnet to keep from overpowering it and weakening the flux at the VC gap


I feel difference  for good, and not got any damage from completed mod.

The only disadvantage that the magnetic caps now attract to them metal obstetrical.
And on sticking mod process  you could damage the drivers by it self and it connections.


----------



## Slater

Sharpty said:


> Also by adding magnets that are stronger than the speaker magnet itself, you can significantly weaken the field across the VC. Bucking magnets are usually 60-80% as powerful as the driver magnet to keep from overpowering it and weakening the flux at the VC gap



This is why I personally always use a smaller diameter magnet. It lessens the chance of being more powerful than stock.


----------



## Cruelhand Luke (Dec 21, 2018)

I went back and re-read my first impressions when I 'super ultra magnetized'(tm)** *my 9500s. I did several headphones at the same time.
I don't have measurement rigs and have only a passing interest in looking at graphs. I don't live by them because there are so many other variables that affect the way one perceives sound: what is the size and shape of your head, do you wear glasses, are the headphones properly amplified, do you live at sea level or in the mountains, how old are you, how well do you actually hear...on and on...
I figured I would add magnets to all of my headphones that were good candidates for it and see if anything sounded different.
I listened to a list of songs I know really well...
In broad terms I thought there were 3 possible outcomes:
1) all of them sounded better which might mean placebo or it might mean adding magnets works really well.
2) none of them sounded better which might mean that everybody _except _me was experiencing the placebo effect
3 )some of them sounded better, some didn't....which to my mind indicates it does work, on some headphones (and some people could also be experiencing the placebo effect)
in my limited, person, subjective opinion...some sounded better. The 9500s stands out. The magnets were a last little mod that took them to the next level in terms of sound. On the other hand a really well thought out, well designed and beautifully built headphone, the Fidelio L2? I didn't notice any improvement adding magnets, it was perfect as-is.

* I don't recall where I read this phrase, but somewhere along the line another forum member who I think is from Brasil asked a question about stacking magnets and used the phrase 'super ultra magnetized' ...it's such a cool combination of words, I mean putting 'super' with 'ultra' is fun,
but throwing Magnetized in there is genius.
I hope y'all pick up my new solo album, "Cruelhand Luke, Superultramagnetized"


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## Cruelhand Luke (Dec 21, 2018)

...but a question remains.
Did the magnets help the sound because the drivers were mass loaded and therefore damping of the driver occurred resulting in a 'cleaner' sound? In the same way adding blutak, dynamat or sorbothane would affect the sound by limiting unwanted resonances? Or did the super ultra magnetized waves do it?
I think it's both. I think in some headphones the combination of a stronger magnet and the added damping on the stock magnet results in better sound.


----------



## Sharpty

Cruelhand Luke said:


> .....Which begs the question....


Where can I get a copy??


----------



## Cruelhand Luke

Sharpty said:


> Where can I get a copy??


Wait for it. It's going to be epic.


----------



## Sharpty (Dec 22, 2018)

Some more posts about bucking magnets that I found:

https://www.diyaudio.com/forums/multi-way/28698-adding-magnets.html

https://www.diyaudio.com/forums/subwoofers/295607-mounting-magnet-magnet-issue.html

You may be able to add a bucking magnet without adhesive, It should repel at first but once it is very close to the driver magnet, it will attract. At least this is the case for speakers.

Also i've noticed that cheap chinese Neo magnets can vary widely in magnetic strength. I bought about 25 small "n50" cylindrical neos a few years ago and some hardly worked at all while some were very strong. Idk how you would find a matched set.


----------



## Slater

Sharpty said:


> Some more posts about bucking magnets that I found:
> 
> https://www.diyaudio.com/forums/multi-way/28698-adding-magnets.html
> 
> ...



To truly get a matched pair, you’d need to measure it on a gauss meter (aka Tesla meter).

Hobby grade ones run about $100, and lab grade ones can run $20k.

Most can also identify N and S poles, which is handy for our purposes.


----------



## Sharpty

Slater said:


> To truly get a matched pair, you’d need to measure it on a gauss meter (aka Tesla meter).
> 
> Hobby grade ones run about $100, and lab grade ones can run $20k.
> 
> Most can also identify N and S poles, which is handy for our purposes.



Need to find a layman's alternative, like seeing how many ball bearings or nuts you can pick up in a chain


----------



## legopart

Slater said:


> To truly get a matched pair, you’d need to measure it on a gauss meter (aka Tesla meter).
> 
> Hobby grade ones run about $100, and lab grade ones can run $20k.
> 
> Most can also identify N and S poles, which is handy for our purposes.


You can buy a compass for only $1


----------



## Slater

legopart said:


> You can buy a compass for only $1



Well that will identify N and S, but not give a quantitative measurement of the gauss of the stock magnet, matching a set of extra magnets, and the resulting final gauss from stacking. It also won’t allow the measurement of the difference between stacking the extra magnet with the poles in attracted vs repelled mode.

What I could do is contact a few local universities and see if any have a gauss meter, and if so ask if I can use it for a few hours.

Another option is to buy one, use it, and return or resell it.


----------



## Sharpty (Dec 22, 2018)

Slater said:


> Well that will identify N and S, but not give a quantitative measurement of the gauss of the stock magnet, matching a set of extra magnets, and the resulting final gauss from stacking. It also won’t allow the measurement of the difference between stacking the extra magnet with the poles in attracted vs repelled mode.
> 
> What I could do is contact a few local universities and see if any have a gauss meter, and if so ask if I can use it for a few hours.
> 
> Another option is to buy one, use it, and return or resell it.



If you really want one, you can get one with a probe for $100
https://www.amazon.com/Gaussmeter-F...8&qid=1545523128&sr=8-10&keywords=gauss+meter

The problem is that you have to destroy a speaker to measure the flux across the VC gap, so you'd want to find an old junk speaker to play with. You could even get some magnetic viewing film to watch real time changes in the field when adding/removing magnets. But honestly a bit of consideration/ study of magnetic fields makes it rather apparent that adding attracted magnets to the back, is going to pull the field away from the VC gap... contrary to intuition this can actually make the headphones louder to a certain point because the movement/momentum/overtravel of the driver is not as tightly controlled, if i understand correctly. It can also lower the impedance of the speaker.


----------



## mufflertape

UPDATE: so I went back to the drawing board with the stacking magnets on a 58x and I think the improved treble was actually some glare/ringing that the air gap flux was helping with. Also I worked to correctly implement the bucking magnet by the side of repulsion etc. and it worked good at first trying with 2 different magnets but ultimately it caused some distortion so I promptly removed it, sorry for the bust yall. Still worth looking into, but u didn't want to glue the magnets down etc. so maybe someone else can crack the code on that.


----------



## kkl10 (Aug 28, 2019)

What in the name of Jesus is happening here? People trying to do this on the Sennies? Crazy bunch.



Sharpty said:


> a bit of consideration/ study of magnetic fields makes it rather apparent that adding attracted magnets to the back, is going to pull the field away from the VC gap... contrary to intuition this can actually make the headphones louder to a certain point because the movement/momentum/overtravel of the driver is not as tightly controlled, if i understand correctly.



When I stack magnets in the wrong orientation, the bass becomes looser and ill-defined. The whole sound loses definition and becomes veiled. Major loss of resolution. Earlier roll off at both ends of the spectrum. If I remember correctly, I might have heard some kind of weird distortion too. But I don't remember perceiving an increase in volume in the short time I experimented with this configuration. Which makes sense, I think, because stacking the magnet in the wrong orientation weakens the grip over the voice coil and, consequently, impulse response.

On the other hand, one of the typical effects of stacking magnets to the back of my GMP 400 drivers in the correct orientation is an effective decrease in the volume. The stronger the magnet (same size and weight), the greater the effect. This is often accompanied by the perception of a slightly tighter bass response, a smoother sound, etc... *Addendum*: this paragraph is true only with the stock acoustic paper on the back of the drivers.

The difference between correct and incorrect magnet orientation is quite obvious with my GMP drivers. I've commented about it earlier in this thread.


----------



## kkl10 (Feb 24, 2019)

Should update my findings. I previously said that stacking magnets on my GMP drivers (specifically, GMP400/450 drivers) caused a decrease in volume. That was when the drivers had the original acoustic paper in place. This paper was covering the tiny back vents. Neglected to mention this detail. I recently decided to remove the acoustic paper and now additional magnets don't result in lower volume output. It's about the same, possibly slightly louder with the magnets. More importantly, the extent of improvement is much greater given that the drivers are freer to move, a little underdamped. However, I'm not sure this is better than with the acoustic paper in place. With the paper in place, it was too easy to turn the sound too thin and bright. Without the paper, it's difficult to get rid of the slight sluggishness in the lower frequencies even though I prefer the larger and more impactful presentation this way. These GMP4xx driver are difficult to get right. Still have to test this with mass loading and some more damping to find the right balance.

Got an MB Quart QP 90X. Drivers feature a huge back vent. A strong ring magnet on the back improves the sound tremendously and actually raises the volume output a lot. Not sure if the magnets of these driver are ferrite, they sound pretty sluggish without an additional magnet but full of life and dynamic with one. Easy to get top tier worthy sound quality with this one. Unexpected observation with these drivers: the right orientation of the magnets is that which initially appears to be the wrong one due to the repelling effect at a distance. When brought really close to the drivers, it sticks with a lot of force though. The GMP250 drivers look very similar, need to get a working unit to test.

Didn't like the results with the closed on-ear Beyerdynamic Custom Street. Don't recommend messing around with the insides of these small closed headphones with adjustable bass vents. These sound much better with some mass loading on the outside (ugly but worth) and a cable replacement. Stock cable is crap.


----------



## dhruvmeena96 (Oct 9, 2019)

@Slater...

If we put the magnet in the orientation in which they attract... Aren't you loosing on the flux which is moving outside the magnetic field..
Normally they design drivers to have most of the field in center via adding steel or magnetic deflector and flux guider...the silver part which is noticeable to eyes....

So stacking the magnet in attracting polarity, may increase the area of flux produced by magnet...which may improve the sound....but we then also loose the magnetic flux in air mostly...so overall improvement on flux density may be 30% over stock on simulation with my Peerless HPD50N headphone driver...

If you can get MU metal tape and some steel...I think we can guide most magnetic nature back to main

And have a magnet with inner edge to be magnetized...

(Image was bad...due to my hand)
The slashed line is a magnetic deflector...


Sorry for bad image...bare with it...I will upload a better diagram

This way we can take most of the flux density concentration back into coil.... Have the driver surface demagnetized and so not prone to attracting stuff on the way plus should it with magnetic interference


----------



## Slater

Try it out and let us know! I’d be very curious myself.

One of these days I’m going to invest in a lab grade gaussmeter (and reference test magnet), which will be very interesting to use for testing many of these theories.

Until then, we just have to try different things and experiment, using our ears to see what the effects are.


----------



## dhruvmeena96 (Oct 9, 2019)

Slater said:


> Try it out and let us know! I’d be very curious myself.
> 
> One of these days I’m going to invest in a lab grade gaussmeter (and reference test magnet), which will be very interesting to use for testing many of these theories.
> 
> Until then, we just have to try different things and experiment, using our ears to see what the effects are.






I think this might be possible if we can get some steel housing for magnets

And if we can get a cylindrical thin axial magnet with two layer of concentric magnet...

Inner circle is south and outer circle is north(or vice versa according to driver magnet structure)


Took a break from building iem and trying to perfect the Peerless HPD50 driver from Parts express...

This driver is used in kennerton vali and has its whole specsheet released... Which Is helpful as thus I will be upgrading circuitry according to magnets changing the way the flux works, having way more fine control on driver


Or we can order different type of magnets and create a concentric hall back array magnet with super power at north pole and then add a steel cap over it...to redirect flux...

That would be even more crazy


That would be easier to do plus it needs the axial ring magnets and rectangular magnet...to redirect my north pole flow...

And actually I mean way easier

According to my estimation...we can reach 1.8Tesla force if we can get a Hall back array in ring shape
sissue

Like this..


 


But then we have to get a steel cap with cut out for magnet with equal distance...otherwise magnets are pretty easily available...

The ring figure bellow is the structure of magnets as how we will see it..


We might hit a lot of magnetic flux plus some no flux on the down part, which makes the driver magnet assembly itself shielded...

That would be more than Beyer Tesla driver....

Hahaha

Having higher field by piggybacking magnet
1. Increase sensitivity because overall field was increased

2. Lowering Qts slightly by lowering Qes

3. Dramatically increase stray magnetic field(which has to be shielded)


But in Hall back array, we can eliminate the 3rd issue.

Qts mostly apply to speaker resonant frequency or where speaker may suck up too much signal voltage..

As we can see speaker impedance..they have peak at low frequency... That's what makes speaker bassy... As more voltage sucked in, means more energy thrown out...and resonant frequency means that speaker ....if moved manually at that specific frequency manually, will produce back emf..

Piggybacking magnet technically lower Qts.

Which means that you are damping the speaker movement itself..

Some people use foam inside the headphone cups to do the same...you are just doing it with speaker... And way more effectively..

And since the damping effect comes in place...speaker technically sucks less voltage inherently on resonant frequency which gives it flatter impedance... And as the resonant frequency is lowered....less back emf is generated


So you are

1. Reducing bass resonant frequency
2. Reducing Back emf which leads to lower linear and non linear distortion
3. More magnetic flux means way more control and less oscillations of diaphragm like modal breaks(making things sound tighter)
4. Higher sensitivity





I can make simpler structure to concentrate magnetic fields...
Which can also be done by everyone...


The above one are just concept .



And yah

N55 magnets are available now..

Those MotherF***** are crazy..

I was not able to lift them off from my iron block at all...they are so strong that if other magnet is separated with just a plastic plate.. And they are attracting each other...they can break themselves and the plastic plate


----------



## dhruvmeena96

Since everyone is working with axial cylindrical magnet with punch hole.
i will try using simulations and will find the way to concentrate a lot of magnetic flux back to motor
because i have general proof of concept but lemme try

search for steel and EMF sheilding and magnetic flux guides

and my project may require usage of steel at different places but simple enough to get the cutting.... no complex magnet casing and CNC stuff.... you might be able to find these stuff and also will try to keep most of the cost down

Aim is 1.5Tesla to coil


----------



## Sharpty

All this seems rather absurd to me. The magnet of a driver in any decent headphone, is part of the tuning design. It's not like the engineers with hundreds of thousands of dollars in test equipment, are just slapping any old random magnet on there and hoping it sounds good. It seems pretty ridiculous to assume that slapping a random magnet on it yourself, is actually improving the sound at all. Changing it, yes, improving it, I highly doubt.


----------



## Slater (Oct 9, 2019)

Sharpty said:


> All this seems rather absurd to me. The magnet of a driver in any decent headphone, is part of the tuning design. It's not like the engineers with hundreds of thousands of dollars in test equipment, are just slapping any old random magnet on there and hoping it sounds good. It seems pretty ridiculous to assume that slapping a random magnet on it yourself, is actually improving the sound at all. Changing it, yes, improving it, I highly doubt.



You’re totally entitled to your opinion. And you may be right. Who knows?

However, I could make the same argument about doubting that numerous other mods don’t make any difference too, such as changing earpads on headphones, ear tips on earphones, nozzle filters, dampening earphone cups, tuning foam, tweaking driver and air vents, etc. But the reality is, that’s not the case.

There’s so many mods that can improve the sound of earphones and headphones, over and above what “_the engineers with hundreds of thousands of dollars in test equipment_” came up with, that it’s impossible to list them all.

The difference is that you don’t know until you experiment and try for yourself. You’ll never learn anything sitting in an armchair and doing nothing but speculating.


----------



## Sharpty

Slater said:


> You’re totally entitled to your opinion. And you may be right. Who knows?
> 
> However, I could make the same argument about doubting that numerous other mods don’t make any difference too, such as changing earpads on headphones, ear tips on earphones, nozzle filters, dampening earphone cups, tuning foam, tweaking driver and air vents, etc. But the reality is, that’s not the case.
> 
> ...



Fair enough. Although I would say there is a difference between custom earpads to make your headphones seal better, and changing the magnetic field of a precision driver. 

I'm not going to take apart my headphones and experiment tho. Especially not based on subjective claims of improved sound by people with no real background in audio or speaker design. 

Anyway, greetings from Cincinnati.


----------



## dhruvmeena96

Sharpty said:


> All this seems rather absurd to me. The magnet of a driver in any decent headphone, is part of the tuning design. It's not like the engineers with hundreds of thousands of dollars in test equipment, are just slapping any old random magnet on there and hoping it sounds good. It seems pretty ridiculous to assume that slapping a random magnet on it yourself, is actually improving the sound at all. Changing it, yes, improving it, I highly doubt.


Its all about flux and how it react with voice coil and its former..

It affects Qts and impedance chart..

And its not about improving sound per se...its all about experiment.

Tried with some drivers and they dont read well. Proper engineered driver always have Qts of 0.7, which is critically damped....and there, adding a magnet will technically kill bass response by over damping it.

Warm headphones with slightly boosted bass reacts well or grado reacts well..

Its because there Qts is high.

I won't be stacking magnet on Focal Utopia or HD800. Even HD600.

I would rather go for electrical solution, pad swap or structural mod(HD800SDR)

But modyfing cheap low budget mass level Headphones...its s good experiment.

Or if you want to create your own headphones..

I have my own separate driver from peerless (they only make headphone drivers and not headphones). Kennerton Vali and Aurorus Borealis and Australis uses that driver.

Let's see what we can do with it.


In the end its preference, some believe pad swap is for comfort and some do it for sound change...

Many people in loudspeaker industry are doing that for having larger flux though....


----------



## Slater

Sharpty said:


> I'm not going to take apart my headphones and experiment tho. Especially not based on subjective claims of improved sound by people with no real background in audio or speaker design.



That's the great thing about living in a free society. You can do what makes you happy, and I can do what makes me happy. Take care


----------



## dhruvmeena96

Sharpty said:


> Fair enough. Although I would say there is a difference between custom earpads to make your headphones seal better, and changing the magnetic field of a precision driver.
> 
> I'm not going to take apart my headphones and experiment tho. Especially not based on subjective claims of improved sound by people with no real background in audio or speaker design.
> 
> Anyway, greetings from Cincinnati.


OK...I read that now....

Damm bro hard

OK, I am not from audio society whatsoever...but I am a scientists for govt. Here.

And see, what you guys call drivers are actually electrical transducer which is often denoted as electrical motor in electronic circuit..

Having more flux around magnet gives it higher control and torque and also higher regenerative braking(take it as braking).

Less magnetic force makes it more resonant at resonant frequency, and dynamic driver have this on low end.. Which leads to less control over that point, and what we hear ad bass characterstics.

Qts is suspension setting of motor or shock rating. The suspension must prevent any lateral motion that might allow the voice coil and pole (or core) to touch. The suspension acts as a shock absorber. Qms is the mechanical Q, which measures the control from the speaker’s mechanical suspension system, the surround and spider. Think of these components as springs. Qes is the electrical Q, which measures the control from the speaker’s electrical suspension, the voice coil and magnet. Opposing forces from the mechanical and electrical suspensions act to absorb shock. Qts is the total Q of the speaker and is derived from an equation where Qes is multiplied by Qms. The result is divided by the sum of the same.

Qts under 0.4 means suspension is overdamped(no feeling or dynamics but more ideal). Bass is very tight. In speaker analogy, you need either a woofer crossover or vented box. Headphone will translate to tighter and resolved bass but no feeling in it.

0.1 sounds like farty bass


More than 0.4 and less than 0.7 is critically damped. And speaker analogy, it means that speaker with specific Inductance, impedance and material selection and proper study has ended up making critically damped motor/transducer. This may sound neutral to you guys with good extended bass as we go near 0.7.

Above 0.7 is under damped motor or a motor which can distorts, modal breaks etc.

Its like a car with worst suspension and when moved on road of bad quality music...it shows... 

Bleeding bass in mids..overly warm and no detail whatsover....some speaker may be exception to detail part....but mostly they are very bassy.



Adding magnet is gives you more flux, so coil becomes more sensitive around more passing line of magnetic field, thus giving it more control. This lowers Qts.

And also flattens impedance..

This theory works...its just that we all are doing DIY and can only do subjective claims..

Its just that, how we learn and optimise the magnetic field around the driver in most simplistic manner..

I will see on that as I have more resources to do that.

And I will only use single axial magnet...and some steel as magnetic flux waveguide


----------



## Sharpty

Very well. I understand the general concept of a "driver" and how VC control and resonance play into audio reproduction. It seems you have a good understanding of it. 

You can gain efficiency and output in the higher frequencies by adding field strength, but at the cost of less resonance and therefore less output in the lows, roughly speaking.

I think i posted earlier and you brought it up as well, but it seems that putting a magnet in the attracted direction would pull the field away from the coil gap. If you put a repelling magnet on the driver, it should direct the field towards the VC gap. I've seen this done on cheap speakers, at least i'm fairly certain they were in reverse orientation.


----------



## dhruvmeena96

Sharpty said:


> Very well. I understand the general concept of a "driver" and how VC control and resonance play into audio reproduction. It seems you have a good understanding of it.
> 
> You can gain efficiency and output in the higher frequencies by adding field strength, but at the cost of less resonance and therefore less output in the lows, roughly speaking.
> 
> I think i posted earlier and you brought it up as well, but it seems that putting a magnet in the attracted direction would pull the field away from the coil gap. If you put a repelling magnet on the driver, it should direct the field towards the VC gap. I've seen this done on cheap speakers, at least i'm fairly certain they were in reverse orientation.


It kinda pull magnetic effect away from driver, but driver flux guide still maintain the magnetic flux wave path and shape...the result is slightly increased magnetic field but a lot of stray field.
This increase the magnetic field lines

Doesnt helps in driver shielding... Actually worsen it up if used above N50



Putting it in repelling position increase resonance... But it has to be done in such a way that other pole(not stuck to anything) is shielded to get that effect..
It concentrates the magnetic field lines.

Also helps in driver shielding... 

But can kill magnetic force over period of time and thus kill driver


----------



## dhruvmeena96

@Slater 
I am taking breaks from building iems for now.

That's why I am party crashing on your thread


----------



## dhruvmeena96

skwoodwiva said:


> iso tried out this mod, krk woofer, Fluke 287, 3oz gel ball  dropped from fixed hight.  Etc etc
> Pic lost when phone died.
> Results nadda.  3 x the magnet size w/ proper neos, or a 3 magnet set up with idenical krk magnets.
> Not a bit of peak recorded mv ac or dc noticed.
> ...


Ehhhh bro

You did the wrong test

Because that parameter only changes when you upgrade the voice coil itself

Magnets won't change the voltage parameters
 Magnets are used to convert that electrical signal to mechanical signal

If you can measure

Measure THD, distortion, FR, and slow motion recording of nodal breakdown due to loose magnetism


----------



## willyboyaudio

Edifier H840 can use 20mm diameter and 5mm center hole. Thickness doesn’t matter as much.
Sorry I cannot post pictures right now, but they can be seen here:

https://willyboy.home.blog/2020/02/29/magnet-stacking-edifier-h840/

Thank you for the great idea of stacking magnets, I thoroughly enjoy it.


----------



## Slater (Feb 28, 2020)

willyboyaudio said:


> Edifier H840 can use 20mm diameter and 5mm center hole. Thickness doesn’t matter as much.
> Sorry I cannot post pictures right now, but they can be seen here:
> 
> https://willyboy.home.blog/2020/02/29/magnet-stacking-edifier-h840/
> ...



Glad you are enjoying it!

I got a Fidelio X2HR a few months ago, and I never cease to be amazed at the difference the magnets make. It made a great headphone sound even better, and it only cost me a few pennies.

I appreciate the Edifier H840 info. I’ve added your measurements  to the 1st post


----------



## willyboyaudio

Slater said:


> Glad you are enjoying it!
> 
> I got a Fidelio X2HR a few months ago, and I never cease to be amazed at the difference the magnets make. It made a great headphone sound even better, and it only cost me a few pennies.
> 
> I appreciate the Edifier H840 info. I’ve added your measurements  to the 1st post


In my case, the chamfered side is ‘down’ and the flat side is ‘up’, because this is the position that gives stronger pull to the driver. Is there another way to verify I got it in the right orientation? Thank you.


----------



## Slater

willyboyaudio said:


> In my case, the chamfered side is ‘down’ and the flat side is ‘up’, because this is the position that gives stronger pull to the driver. Is there another way to verify I got it in the right orientation? Thank you.



That’s the way I usually do it.

You can also try it both ways and see if you hear a difference.

Personally, I have been unable to hear a difference. In other words, I can definitely hear a difference with no magnet vs with a magnet. But I can’t really tell a difference with the magnet being flat side up vs flat side down. Maybe someone else can, whose ears are better than mine.


----------



## willyboyaudio

Slater said:


> That’s the way I usually do it.
> 
> You can also try it both ways and see if you hear a difference.
> 
> Personally, I have been unable to hear a difference. In other words, I can definitely hear a difference with no magnet vs with a magnet. But I can’t really tell a difference with the magnet being flat side up vs flat side down. Maybe someone else can, whose ears are better than mine.



Thanks Slater, really appreciate it. I also put 0.12 grams of blu-tack to fill the chamfer so it’s ‘coupled’ to the bass port. Nothing scientific about the weight, but that’s the amount that was needed to fill the cavity.


----------



## Slater

willyboyaudio said:


> Thanks Slater, really appreciate it. I also put 0.12 grams of blu-tack to fill the chamfer so it’s ‘coupled’ to the bass port. Nothing scientific about the weight, but that’s the amount that was needed to fill the cavity.



Great idea - can’t go wrong with mass loading the driver even more


----------



## willyboyaudio

After listening for 2 weeks, I found my H840 rather lifeless, so much that I put it in storage, in favor of my SR850. Then I tried reversing the magnets again, this time chamfered side up. I tried listening without additional magnets, chamfered side down, and chamfered side up. I conclude that chamfered side down brings out the mids but the rendition is lifeless. Putting it chamfered side up seems to bring things back to normal and then improve some.


----------



## legopart

willyboyaudio said:


> After listening for 2 weeks, I found my H840 rather lifeless, so much that I put it in storage, in favor of my SR850. Then I tried reversing the magnets again, this time chamfered side up. I tried listening without additional magnets, chamfered side down, and chamfered side up. I conclude that chamfered side down brings out the mids but the rendition is lifeless. Putting it chamfered side up seems to bring things back to normal and then improve some.


Less then 1$ for polarity measurement tool
https://www.ebay.com/itm/30mm-Mini-...el-Navigation-Wild-Survival-T-SE/133273684886


----------



## Slater

willyboyaudio said:


> After listening for 2 weeks, I found my H840 rather lifeless, so much that I put it in storage, in favor of my SR850. Then I tried reversing the magnets again, this time chamfered side up. I tried listening without additional magnets, chamfered side down, and chamfered side up. I conclude that chamfered side down brings out the mids but the rendition is lifeless. Putting it chamfered side up seems to bring things back to normal and then improve some.



Nice. I agree that you really need to try the magnets both ways.

There’s no way to know what pole orientation the stock magnet is using. So trying the stacked magnet both ways allows you to check for any differences that may exist.


----------



## legopart

Slater said:


> Nice. I agree that you really need to try the magnets both ways.
> 
> There’s no way to know what pole orientation the stock magnet is using. So trying the stacked magnet both ways allows you to check for any differences that may exist.


With compass you can check the polarity without open the headphones.


----------



## spencexxx

Has anyone tried this with Koss porta pro or _KSC75?_


----------



## Slater

spencexxx said:


> Has anyone tried this with Koss porta pro or _KSC75?_



Is there enough room? I thought the back of the driver has a plastic housing with integrated clip that the ear clips attach to?


----------



## spencexxx

Slater said:


> Is there enough room? I thought the back of the driver has a plastic housing with integrated clip that the ear clips attach to?


It does, but I thought maybe it could be dremeled a bit.  Was wondering if anyone had gone down that path yet


----------



## 528068

Would stacking on a 500ohm driver be safe or/and benefit or not-benefit anything?


----------



## Slater

TheRealestLad said:


> Would stacking on a 500ohm driver be safe or/and benefit or not-benefit anything?



If it will physically fit, go for it. I haven’t found a driver yet that it didn’t make a positive difference on. Some more than others.


----------



## 528068

Slater said:


> If it will physically fit, go for it. I haven’t found a driver yet that it didn’t make a positive difference on. Some more than others.



Stacking magnets on a dynamic driver will always have the driver do its _dynamic-driver thing _(how they work) dryer or in other words faster, right? And sometimes stacking a magnet on a driver can be a bad thing for some people because they may find the modified driver response too dry? Or holes being covered? I'd like to do this on a K99/K100 or that 40mm Ora driver from Aliexpress. I will be using M2 as the shell when I am able to get a hold of any of the three and I can modify the M2 to fit bigger magnets.


----------



## 528068 (Jun 23, 2020)

Also what should I look for and know about when I want to stack a magnet onto a driver and does the size of the magnet affect how the magnet itself affects the driver's power? And what magnet should I get to have the drivers as more powerful as possible?


----------



## Slater

TheRealestLad said:


> Also what should I look for and know about when I want to stack a magnet onto a driver and does the size of the magnet affect how the magnet itself affects the driver's power? And what magnet should I get to have the drivers as more powerful as possible?



There’s valuable information in the thread. I’d strongly recommend reading through it, because I’m sure your questions will be answered. If not, let us know


----------



## Slater

TheRealestLad said:


> Stacking magnets on a dynamic driver will always have the driver do its _dynamic-driver thing _(how they work) dryer or in other words faster, right? And sometimes stacking a magnet on a driver can be a bad thing for some people because they may find the modified driver response too dry? Or holes being covered? I'd like to do this on a K99/K100 or that 40mm Ora driver from Aliexpress. I will be using M2 as the shell when I am able to get a hold of any of the three and I can modify the M2 to fit bigger magnets.




In my experience (doing it to about 30+ headphones so far), it mainly seems to tighten the sub bass and bass frequencies, and in many cases reduce or eliminate low frequency distortions.

I’ve never noticed any dryness. Not sure who told you that. Or maybe it’s on a headphone I’ve not tried it on?

As far as holes being covered, no the idea is to make sure NO holes are covered when stacking a magnet. That’s why if a stock driver has a vent in the center of the stock magnet already, you need to make sure you stack a magnet that also has a hole in the center. If any stock driver holes get covered, the sound tuning will change (which is not desirable).


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## 528068

Slater said:


> In my experience (doing it to about 30+ headphones so far), it mainly seems to tighten the sub bass and bass frequencies, and in many cases reduce or eliminate low frequency distortions.
> 
> I’ve never noticed any dryness. Not sure who told you that. Or maybe it’s on a headphone I’ve not tried it on?
> 
> As far as holes being covered, no the idea is to make sure NO holes are covered when stacking a magnet. That’s why if a stock driver has a vent in the center of the stock magnet already, you need to make sure you stack a magnet that also has a hole in the center. If any stock driver holes get covered, the sound tuning will change (which is not desirable).



When I mention about "dryness" or/and "dry" I mean like how fast the sound the driver makes decays.


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## willyboyaudio (Jul 23, 2020)

Hi Friends,

I'm happy to share my findings after experimenting with stacking magnets on Sennheiser HD202-ii.
To quote our guru:


Slater said:


> In my experience (doing it to about 30+ headphones so far), it mainly seems to tighten the sub bass and bass frequencies, and in many cases reduce or eliminate low frequency distortions.



I agree, and measurements indicate this to be true.

Bass: Smoother bass in the 20-40Hz region. I'm not sure if the drivers are playing those notes, not cleanly anyway, so perhaps this shows that stronger magnet gives *better control**. *50-300Hz is identical to the stock unit.

Midrange: 300-3000Hz is identical to the stock unit.

Treble: Now this is where it gets interesting. Using a ring magnet, 20x2mm with 5mm hole, there is a massive dip between 7and 9kHz. This magnet is wider than the stock magnet, maybe it's messing the magnetic field of the original magnet? Around 10-13kHz, this combo is about 2dB hotter than stock. 
Not happy with the dip, I then stacked two of 10x2mm coin magnet. Compared to stock, this results in 2dB cut around 6-7kHz and 2dB boost around 10-13kHz. To me, this means *less sibilance* and *better shimmer*. Tambourine sounds with realism I've never heard before with this pair. Not only more presence, but more accurate timbre, in my subjective opinion. 

Perhaps this is also a good time to mention that the stock magnet on the HD202-ii is a strong one. 15mm in diameter, and looks like a neodymium magnet. It is very decisive on pulling/pushing so it's very easy to determine the polarity.

I measured using REW and Dayton Audio UMM-6 mic, calibrated. I will not show my measurements because I am not confident of their accuracy. I just use it for my own learning, such as in this case, telling me if my mods are doing anything, or if my ears are fooling me. I took 3 measurements each side, and averaged them. Then I averaged the left and right for each setup. That means, the above conclusion is reached after 18 measurements. Not bragging, just wanted to share my method. Hope this is of some use to all of us.  

20mm ring magnet is bigger than the stock magnet. Will update this post with the final setup soon.


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## Slater

willyboyaudio said:


> Hi Friends,
> 
> I'm happy to share my findings after experimenting with stacking magnets on Sennheiser HD202-ii.
> To quote our guru:
> ...



Wow, very interesting! I’ve never noticed any treble changes. That is awesome that stacking magnets could possibly be used to tweak treble (for treble that’s too hot for example).

Perhaps it is because it is a larger than stock magnet? I’ve only ever used magnets that are smaller than the stock magnet (only because that’s what I have on hand).

You could also try flipping the magnet over and seeing if that changes anything.

In any event, I’m glad you like the results, and I’m excited to hear about any updates


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## willyboyaudio

Slater said:


> Wow, very interesting! I’ve never noticed any treble changes. That is awesome that stacking magnets could possibly be used to tweak treble (for treble that’s too hot for example).
> 
> Perhaps it is because it is a larger than stock magnet? I’ve only ever used magnets that are smaller than the stock magnet (only because that’s what I have on hand).
> 
> ...


Hi Slater, I also suspected it was because of the ring magnet being larger than the stock magnet. I ended up replacing it with two stacked 10mm coin magnets. I formatted my post above a little bit so it's easier to read haha sorry for the confusion.  






willyboyaudio said:


> Treble: Now this is where it gets interesting. Using a ring magnet, 20x2mm with 5mm hole, there is a massive dip between 7and 9kHz. This magnet is wider than the stock magnet, maybe it's messing the magnetic field of the original magnet? Around 10-13kHz, this combo is about 2dB hotter than stock.
> Not happy with the dip, I then stacked two of 10x2mm coin magnet. Compared to stock, this results in 2dB cut around 6-7kHz and 2dB boost around 10-13kHz. To me, this means *less sibilance* and *better shimmer*. Tambourine sounds with realism I've never heard before with this pair. Not only more presence, but more accurate timbre, in my subjective opinion.


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## 528068

willyboyaudio said:


> Hi Slater, I also suspected it was because of the ring magnet being larger than the stock magnet. I ended up replacing it with two stacked 10mm coin magnets. I formatted my post above a little bit so it's easier to read haha sorry for the confusion.


How does the two of the 10x2 magnets compare to single 20x2? Also wont taller magnets results in better magnetic strength than a wider but shorter one?


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## Slater

TheRealestLad said:


> How does the two of the 10x2 magnets compare to single 20x2?



Single is always stronger than 2 stacked up. There are magnetic flux losses with each additional magnet.

 The ideal setup for this mod is ONE  thick magnet.


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## willyboyaudio

TheRealestLad said:


> How does the two of the 10x2 magnets compare to single 20x2? Also wont taller magnets results in better magnetic strength than a wider but shorter one?


I cannot tell the difference by listening, but the fact that the 20mm is wider than the stock 15mm magnet makes me a little bit uncomfortable. 
In my case, my 2x10x2 is subjectively stronger than the single 20x2. There is no fixed N rating of the magnets, so it's all subjective by feeling how they pull towards a metal ruler.
Measuring the sound, 20mm magnet causes a big dip between 7 and 9kHz. The stacked 10mm do not have that problem. They control the bass equally well. 
Hope that helps!


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## Slater (Jul 25, 2020)

willyboyaudio said:


> Measuring the sound, 20mm magnet causes a big dip between 7 and 9kHz. The stacked 10mm do not have that problem. They control the bass equally well.



Good to know! Maybe I need to start trying this 

It just goes to show you, there’s never one answer. Each of us have to try different mod configurations on OUR specific setup, and see what happens! Because what works for one person on 1 model headphone may be totally different than someone else on their different headphone.


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## vtr1000

This mod sounded interesting as it's cheap & totally reversible, so I gave it a go on my SHP9500s with some countersunk 15x3mm N52 magnets comprising a 4mm hole. With a single magnet each side it made a noticable change and stacking a second made that difference more prominent. It was interesting as they sounded more dynamic with the both the highs and lows extending further and with increased soundstage. It sounded like an improvement but with time it became fatiguing and I also found that it made the headphones fussy with music and sources - I was no longer able to enjoy these headphones when plugged into a dongle dac or when playing anything recorded less than perfectly. For this reason, I've removed the magnets and will find a use for them in the garage instread...


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## dhruvmeena96

Sorry for leaving party back in the day
I did try the mod
And did try to make hallbach back in the day(impossible with N52 and human hands)

It does take away magnetic flux concentration from coil but overall flux increases. This kinda make diaphragm for fast while restricting its max Xmas(this is my theory) limiting Xmas action, I feel, give these cheap speaker a planar like hit.. because consumer driver are meant to designed to go loose(under-engineered stuff).
Having it in repulsion orientation, the concentration increases and stock flux remains same.. this leads to more excursion and loudness, which forces the diaphragm and causes distortion.

Theoritically, the repulsion orientation is what you want for way higher flux concentration but the diaphragm becomes bottleneck

The second one has its own advantage there, but stray feilds are bad..
I mean, a pencil sharpner got attracted to my headphone, which the grill protected...lel

Better get some mu metal tape and some steel to make this mod better and redirect stray feilds is the way to go


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## frank2908

Where do you guys get the magnet? İm looking for N50-52 axial round magnet, 3x3 but not sure buying from aliexpress, they can swap n35 and 52


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