[Slater]

I confirmed that there is "16 mm driver units" in the product description on amazon.com below.
https://www.amazon.com/Sony-MDR-ED21LP-Fontopia-In-The-Ear-Headphones/dp/B000094Q77

Next, regarding the shell for the 16mm driver, I found only the set with the driver as shown below.
https://www.aliexpress.com/i/33027019235.html
It is unknown if it is possible to negotiate with the store owner.

Or maybe anyone else on this thread knows!

This shell says “16MM units must have pouches can only be fixed”, whatever the heck that means.
https://a.aliexpress.com/_dWpzFqs

 

[assassin10000]

Thank you very much sir/ madam! I put on my loupes and there it was, on the splitter - MDR-ED21.

The closest on the website database is an MDR-ED238 with a 16mm driver.

Next question - are there any shells that would accommodate this driver?

This is where having a cheap digital caliper (that goes to hundreths of a MM, ie .01mm resolution) would tell you what fits. You could measure the actual driver and the inside of the covers to check clearance. I'm not sure if the actual driver is 16mm or the outside of it's cover.


Here are the 'new' style shells like the B40, cover is 16.7mm O.D. They are larger than the original style PK shells, which O.D is 16.1mm.

 

[Sunstealer]

Thanks guys. I'm waiting on a pair of Edifier H180 to see if they fit any better than the B40. If not, I'll pick up some of those new style pk2 shells and experiment from there. A digital caliper sounds like a good idea too.

 

[assassin10000]

Last week I saw this tear down of the Sabbat X12 Pro's on 52audio.
http://www.52audio.com/archives/6752.html





With this look at how they are internally, I decided to try modifying my Sabbat X12 Pro's to use standard shape drivers and covers. Instead of the original earpod shape ones as those are not 100% comfortable for me, even after I reshaped them.

I did this mostly because I like how much more natural earbuds sound when I want to hear the environment around me compared to the 'ambient' modes I've heard on other TWS (WF-1000XM3 and Buds+). That and I wanted an even more compact package than using my BT20S + MMCX earbud of choice.




Cover off to check clearances and see how much wire was available. No pic of it but the circuit board and battery both lift right up.




Driver and cover off, they come off together. No need to separate them. I pulled the wires out a bit more, for enough length for soldering.

I think the factory has them pulled through the other side to solder to the circuit board. They probably install the drivers first then the circuit board and battery.






Here you can see a slight bit of reshaping the housing where it meets the edge of the driver cover. As the housing edge is a bit wider and overlaps the driver cover a little.

After trying the drivers with no additional port and also a .8mm port, I ended up with an additional 1.0mm port (for now). It can be seen at about the 1 o'clock position from the factory vent located at the bottom of the housing.

The inner lip is smaller than the 14.8mm driver covers, so I used e8000 glue in 4 spots about 3-4mm long to secure the drivers. Some of the residue is visible as I've had the drivers on and off a few times.




Complete (for now ).

I will probably try a few other speaker drivers. It's matter of trying to find a good match with the X12 Pro electronics. As a TWS their internal amp is not near as strong as my BT20S, so higher sensitivity and 32Ω or lower impedance is most likely wanted. The original drivers are 32Ω (verified with my multimeter) and sensitivity is listed as 120db.

I used my extra pair of 32Ω bass unit drivers, as the original X12 ones were lacking some bass. Even with earbud foams I had to EQ them quite a bit. I still do but not as badly.

 

[willyboyaudio]

That's looking great now!

Thanks a lot, GREQ, for your input helps me to get there.

 

[jogawag]

I 've got MMCXed docomo earbuds from @assassin10000! Maybe I am only one person who has black and white MMCXed docomo earbuds in the world(???).

I'm very satisfied with everything about MMCXed docomo earbuds outlook and sound now.
Thanks @assassin10000 very much.

I attach a pic with the single crystal copper cable and silver coating cable connected.

 

[jayeyeanne]

@willyboyaudio as requested, here are pics of my builds. This is really addictive, and I've got another 3 more builds in the pipeline

 

[furyossa]

Hi guys, just finished building these as gift for friends:

Love the type of shell of your B&W edition earbuds. I bought a silver red and blue variant a while back. For now, only silver variant is combined with
a handmade wooden piece.

And this is a complete version

 

[willyboyaudio]

@willyboyaudio as requested, here are pics of my builds. This is really addictive, and I've got another 3 more builds in the pipeline

Amazing work!! How did you stick those artworks to the housing? Are those stickers?
You have some fine artistic touch. Very pleasant to look at. I'm sure they sound as good as they look.

 

[willyboyaudio]

Love the type of shell of your B&W edition earbuds. I bought a silver red and blue variant a while back. For now, only silver variant is combined with
a handmade wooden piece.

And this is a complete version

Looks like some high-end stuff there! Amazing.
In its standard form, that housing boosted up the mid-high too much for me. Is that your experience also?

 

[furyossa]

Looks like some high-end stuff there! Amazing.
In its standard form, that housing boosted up the mid-high too much for me. Is that your experience also?

Nope. By enlarging inner space you will reduce mid-high because the reflection of the sound wave is not the same, it's slower. Also, you will get a more spacious sound.
Resonance in the wood chamber is also present which gives a little flavor to the sound signature. In short original shell simulate "closed-back" sound and modded
(with large cavity) "open-back" sound

 

[assassin10000]

This is what I do.

Clamp the wire in a soldering heat sink with only 3-4mm sticking out.
I put a little flux on the end of the wire.
Get a ball of solder on the tip of the iron.
Then dip 1-2mm of the wire in the solder.

It melts, cleans and tins the ends. Plus it keeps the wire flexible near the ends, if you don't use a heat sink 5-8mm of the coating hardens and becomes way less flexible.

Here's some pics I snapped last night tinning some wires. There is the tiniest little bit of flux on the ends sticking out of the heat sink in the top pic. In the bottom pic you can see the coating has melted back and bubbled just past the solder, this can be easily scraped off with a fingernail.

 

[assassin10000]

Last week I saw this tear down of the Sabbat X12 Pro's on 52audio.
http://www.52audio.com/archives/6752.html





With this look at how they are internally, I decided to try modifying my Sabbat X12 Pro's to use standard shape drivers and covers. Instead of the original earpod shape ones as those are not 100% comfortable for me, even after I reshaped them.

I did this mostly because I like how much more natural earbuds sound when I want to hear the environment around me compared to the 'ambient' modes I've heard on other TWS (WF-1000XM3 and Buds+). That and I wanted an even more compact package than using my BT20S + MMCX earbud of choice.




Cover off to check clearances and see how much wire was available. No pic of it but the circuit board and battery both lift right up.




Driver and cover off, they come off together. No need to separate them. I pulled the wires out a bit more, for enough length for soldering.

I think the factory has them pulled through the other side to solder to the circuit board. They probably install the drivers first then the circuit board and battery.






Here you can see a slight bit of reshaping the housing where it meets the edge of the driver cover. As the housing edge is a bit wider and overlaps the driver cover a little.

After trying the drivers with no additional port and also a .8mm port, I ended up with an additional 1.0mm port (for now). It can be seen at about the 1 o'clock position from the factory vent located at the bottom of the housing.

The inner lip is smaller than the 14.8mm driver covers, so I used e8000 glue in 4 spots about 3-4mm long to secure the drivers. Some of the residue is visible as I've had the drivers on and off a few times.




Complete (for now ).

I will probably try a few other speaker drivers. It's matter of trying to find a good match with the X12 Pro electronics. As a TWS their internal amp is not near as strong as my BT20S, so higher sensitivity and 32Ω or lower impedance is most likely wanted. The original drivers are 32Ω (verified with my multimeter) and sensitivity is listed as 120db.

I used my extra pair of 32Ω bass unit drivers, as the original X12 ones were lacking some bass. Even with earbud foams I had to EQ them quite a bit. I still do but not as badly.

A few days ago I tried another driver on my X12 Proo's, a pair of 'Sunrise SR2' 16Ω drivers (from chitty's). I'm not a huge fan of these drivers sound signature to begin with but figured since it is a low impedance driver it was worth a shot. They didn't sound very good on the X12 Pro.


A little while ago I swapped my Yuin PK2 drivers on. Much better. Still lacking a bit of bass/sub-bass but this is mostly due to the weak amp in the TWS. Cleaner and better than the ETS and SR2 drivers.

 

[jayeyeanne]

A few days ago I tried another driver on my X12 Proo's, a pair of 'Sunrise SR2' 16Ω drivers (from chitty's). I'm not a huge fan of these drivers sound signature to begin with but figured since it is a low impedance driver it was worth a shot. They didn't sound very good on the X12 Pro.


A little while ago I swapped my Yuin PK2 drivers on. Much better. Still lacking a bit of bass/sub-bass but this is mostly due to the weak amp in the TWS. Cleaner and better than the ETS and SR2 drivers.

Just out of curiosity, would blocking some of the driver holes increase bass?

 

[assassin10000]

Just out of curiosity, would blocking some of the driver holes increase bass?

The internal holes? No, it would reduce.

The external? I've never tried. I suppose if you block the part pointed at the concha and leave the part pointed into the ear canal there could be an increase. But it would be an increase across the board, like turning the volume up.