DIY Earbuds
Apr 10, 2020 at 11:36 AM Post #1,681 of 4,705
Wow, you collect all of these :) Foams and cotton paper has totally different purposes. Semi-transparent ie thin paper is a good choice for the back of the driver to reduce the control of the mids. I personally never use opaque white cotton paper. Foam only for shell tuning
Some of those foams are for the driver, not the shells, i actually like them, the 7:1 sounds excellent on the 400ohm
 
Apr 10, 2020 at 4:46 PM Post #1,682 of 4,705
Some of those foams are for the driver, not the shells, i actually like them, the 7:1 sounds excellent on the 400ohm
I believe you. Anyway is there a difference between 400ohm with metal mesh cover and mx500 plastic cover?
 
Apr 10, 2020 at 5:12 PM Post #1,683 of 4,705
I believe you. Anyway is there a difference between 400ohm with metal mesh cover and mx500 plastic cover?
Seems like the metal has a tiny bit more in the highs, and it's smaller, gets a better seal, giving it a pit more in the sub bass/bass
 
Apr 10, 2020 at 5:51 PM Post #1,684 of 4,705
Seems like the metal has a tiny bit more in the highs, and it's smaller, gets a better seal, giving it a pit more in the sub bass/bass
Opening from the inside (the plastic part behind the mesh) probably affects sound waves differently then mx500 cover. Also, I think that size (diameter) of metal mesh cover is slightly wider around 16mm
 
Apr 10, 2020 at 7:15 PM Post #1,685 of 4,705
Well I don't really have a formal method, I just do it for fun in my free time. :) I learned everything by experimenting a lot, reading stuff on the net, and chatting with hobbyists, and still have so much to learn.
Generally speaking, the tuning starts by selecting the right speaker and shell :) This is the most important and you just have to try out many things to find what you like. The fit in your ears has a strong effect as well, if it's too loose or too deep then you won't get optimal sound.
I like to start with bare drivers and play with the tuning on the shell. I didn't like the preinstalled foam on anything so far. (but there are certain shells that are designed for this kind of tuning so it can work great in some cases) White cotton is useful but I don't have many, just the ones I salvaged from other earbuds so I use it rarely.
What really helps is the ability to measure and analyize the graphs. This way you can really understand what's going on and you can build a library of experiments that you can browse. But this is a messy topic.
My main interest now is finding the best, most comfortable alternatives to mx500 and experimenting with shell mods.

I would advise you to find a speaker model you like, preferably one that doesn't come with preinstalled foam. Then buy multiple pairs of it with a bunch of different shells and tuning foam. This way you can try out things and test them side by side. It's also helpful if you give some time for the evaluation, sometimes our ears need some rest to reset :)

For me choosing foam is the last step, independent from the tuning. I usually stick with trig rain donuts every time. To be honest I havent found the best foam for myself yet
Thanks robar. For now, the speakers and shells are available, so I'm working on optimizing their sound. I've found that the MX500 shells is too small to get a comfortable fit in my ears, so I often look for ways to bolster the circumference.
How can I start measuring earbuds? I have a Dayton Audio UMM-6 mic and REW. I'll do some search on this, but if you have any pointers, I'd appreciate it. :darthsmile:
With my speakers building, I rely on measurements more than my ears (70/30) since, as you said, fatigue, mood, etc vary too much for me to have confidence in my own ears and judgement hehehe.
 
Apr 12, 2020 at 12:30 AM Post #1,686 of 4,705
For peace of mind, I undo the knot and put a clip on. Looks like a sizable increase in ‘enclosure volume’. Taking sighted comparison and confirmation bias in consideration, I feel this mod makes the buds sound bigger, more headphone-like.
I also put white tuning cotton on the driver’s holes. I’m gonna try blu-tack on the vents and report back. Cheers guys!
 

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Apr 13, 2020 at 8:36 PM Post #1,687 of 4,705
After the INTRO I will start this topic with Semi-Large Cavity Size Shell for 130ohm Beryllium driver.
PART1.jpg

For this project, I used a black shell from Chitty's Store. This type of shell is very similar to the shell that I described in this post but there some differences.
With this illustration, I will try to explain what are the pros and cons of this type of shell.
130ohm-semilarge.jpg

Blue text represent PROS, red CONS, and BLACK shared opinion or comment
1. "Straight angle" shape on this shell is the 2nd type in terms of the comfort ("Concave arc" shape is 1st).
2. The angle between the shell and the neck of the shell is 90 degrees.
3. Back-side vent with mesh is present and allows proper air circulation and more spacious sound.
4. Foam width is Ok, between optimal and critical.

5. "A-detail" shows a little space between the shell and cover. So the connection is not good and in this case, we can use glue or double-sided duct tape for a temporary connection, if you plan to play with the tuning.
6. "B-detail": MMCX the connector that comes bundled with the shell also needs some glue work to be able to stay inside shell neck.
One more downside is the length of the neck (a bit longer) and narrower than the diameter of the male MMCX shell which distorts the aesthetics.

7. Although these shells are lightweight, the multi-core cables, because of its weight, tends to rotate the shell and break up the seal. On the plus side, these earbuds can be worn over-ear (not ideal suggestion) or str8-up.
8. The shell shape allows very good air-flow and very low sound reflection.
9. The rotation point is where the earbuds housing touches the earlobe ie ANTITRAGUS.
The last image shows one of 3 additional tuning options.
10. By adding tuning cotton with different diameters of the center hole (where the cable passes to the driver) we can reduce airflow and achieve
the effect similar to smaller cavity shells. Again, it all depends on the type of driver itself. For mid-centric types, I like to use shells with larger cavity size
and for the types where the bass dominates, medium cavity size shells. For this shell, this option is not applied.
11. The 2nd option proved to be the best in this type of shells. I added a tin wool filter in front of the vent to reduce bass and bring back the cleaner mids.
This option is convenient because we can always remove the mesh from the vent and change the filter.

12. Depends on how driver sounds, we can solve the problem by reducing the interior space by using cotton as a fill but in this case, it is not necessary.

I will add my conclusion after part 3.
 
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Apr 14, 2020 at 1:57 AM Post #1,688 of 4,705
After the INTRO I will start this topic with Semi-Open Cavity Size Shell for 130ohm Beryllium driver.
PART1.jpg

For this project, I used a black shell from Chitty's Store. This type of shell is very similar to the shell that I described in this post but there some differences.
With this illustration, I will try to explain what are the pros and cons of this type of shell.
130ohm-semiopen.jpg

Blue text represent PROS, red CONS, and BLACK shared opinion or comment
1. "Straight angle" shape on this shell is the 2nd type in terms of the comfort ("Concave arc" shape is 1st).
2. The angle between the shell and the neck of the shell is 90 degrees.
3. Back-side vent with mesh is present and allows proper air circulation and more spacious sound.
4. Foam width is Ok, between optimal and critical.

5. "A-detail" shows a little space between the shell and cover. So the connection is not good and in this case, we can use glue or double-sided duct tape for a temporary connection, if you plan to play with the tuning.
6. "B-detail": MMCX the connector that comes bundled with the shell also needs some glue work to be able to stay inside shell neck.
One more downside is the length of the neck (a bit longer) and narrower than the diameter of the male MMCX shell which distorts the aesthetics.

7. Although these shells are lightweight, the multi-core cables, because of its weight, tends to rotate the shell and break up the seal. On the plus side, these earbuds can be worn over-ear (not ideal suggestion) or str8-up.
8. The shell shape allows very good air-flow and very low sound reflection.
9. The rotation point is where the earbuds housing touches the earlobe ie ANTITRAGUS.
The last image shows one of 3 additional tuning options.
10. By adding tuning cotton with different diameters of the center hole (where the cable passes to the driver) we can reduce airflow and achieve
the effect similar to smaller cavity shells. Again, it all depends on the type of driver itself. For mid-centric types, I like to use shells with larger cavity size
and for the types where the bass dominates, medium cavity size shells. For this shell, this option is not applied.
11. The 2nd option proved to be the best in this type of shells. I added a tin wool filter in front of the vent to reduce bass and bring back the cleaner mids.
This option is convenient because we can always remove the mesh from the vent and change the filter.

12. Depends on how driver sounds, we can solve the problem by reducing the interior space by using cotton as a fill but in this case, it is not necessary.

I will add my conclusion after part 3.
Nice guide, I am sure it will help a lot of people, great work
 
Apr 16, 2020 at 8:42 AM Post #1,690 of 4,705
Hi guy,
In the efford of pushing an PK1 DIY into the shell I made a driver died (I can measure the impedance before trying pushing it to the shell but they show no impedance after that) are there any way saving it?
Thank.
I broke my EMX500 (PK version 14.8mm) because I pressed the driver on a shell which not has any "lip" that can hold the driver.
Previously driver is glued and I make the beginner mistake. Also, I broke HE150 by pressing the side of the driver trying to separate the driver from the shell which is glued.
You probably ripped the voice coil wires off and to fix it you need to do this.
 
Apr 16, 2020 at 8:50 AM Post #1,691 of 4,705
I broke my EMX500 (PK version 14.8mm) because I pressed the driver on a shell which not has any "lip" that can hold the driver.
Previously driver is glued and I make the beginner mistake. Also, I broke HE150 by pressing the side of the driver trying to separate the driver from the shell which is glued.
You probably ripped the voice coil wires off and to fix it you need to do this.
Thank I guest I'll be more careful next time :D. The fix is too complicated for my clumsy hands :frowning2:
 
Apr 16, 2020 at 8:57 AM Post #1,692 of 4,705
Thanks robar. For now, the speakers and shells are available, so I'm working on optimizing their sound. I've found that the MX500 shells is too small to get a comfortable fit in my ears, so I often look for ways to bolster the circumference.
How can I start measuring earbuds? I have a Dayton Audio UMM-6 mic and REW. I'll do some search on this, but if you have any pointers, I'd appreciate it. :darthsmile:
With my speakers building, I rely on measurements more than my ears (70/30) since, as you said, fatigue, mood, etc vary too much for me to have confidence in my own ears and judgement hehehe.
I measure by pushing the earbud with foam onto the mic of a Tascam dr-05 field recorder. The diameter of the mic barrel matches the earbud front cover perfectly so I don't need any special adapter. I feed the signal of the Tascam into a Focusrite 2i2 which is then processed by REW. I made a post about this here with pictures a few months ago, I think you can find it.
I'm not familiar with your gear, but I can give some general pointers based on my experience. This is my point of view after a lot of reading and experimenting, but this is a controversial topic so others will have different opinions. So first things first, try to bring the mic and earbud as close as possible, to eliminate any extra stuff which would create unnecessary distortions and resonances (just makes the graph unpredictable and hard to understand). Ideally you don't want anything else just the mic, the earbud and some kind of a platform/surface which lets the earbud front cover to sit in front of the mic. Maybe a small rubber ring or something like that, it depends on the shape of your mic. You need some kind of force that keeps the earbud in position, I use my hands as it's the simplest method and the strength of pushing doesn't really matter in my case, only the alignment. The most important thing is to not make a perfectly sealed environment, the seal should come by compressing the edge of the foam on the earbud front cover. (also, look out for the vents on the shell, don't cover them accidentally). But no matter how you do it, just don't expect perfectly unbiased measurements. My simple and straightforward technique gives pretty consistent and readable results, but it's not free from certain peaks. You definitely have to learn how to read the measurements with a critical eye, and there will be certain amount of guesswork no matter what.

So treat the earbud measurements more like a relative comparison, if the setup is consistent then you can compare different tunings perfectly. Choose a baseline, like your favorite earbud and use it as a point of reference. I can redo measurements weeks and months apart and the graphs will match. But don't expect it to be perfectly compatible with any other kind of measurements. You can make educated guesses and compensate in head or even make some rough adjustments in the software, but it becomes speculative.

(edit) By the way, how do you mean that mx500 is too small for your ears? It becomes loose because it doesn't go deep enough, or the diameter is small? There are many shells that have more concave neck than mx500, so they reach deeper thus improving fit. I never had problem with the diameter itself, maybe you can still buy rubber rings that go below the foam, but I would try other shells as well.
 
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Apr 17, 2020 at 8:39 AM Post #1,695 of 4,705
Wow, already received my 3 pairs of favorite 32 ohm drivers that I ordered recently :D
Can't wait to make some backup pairs now :wink:

IMG_20200417_134254~2.jpg
That's great, let's hope they all work well! Will you try them in different shells or tunings? I would be pretty interested in what else you can come up with these speakers :) I have one additional pair on its way too. I will try it in the 6-hole wooden shell and the new plastic nsc shell when it arrives.
 

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