[Sharpty]

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

 

[Slater]

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

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]

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

 

[Sharpty]

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

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]

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]

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]

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]

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]

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]

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]

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]

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]

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

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]

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.