[tony-pro]

Hello,
 
So I'm starting a new IEM project, I have desired to have Sensaphonics IEM's for the longest time ever since they made my shells for  the the classic Westone UM1/Shure E1. I really wanted some 3MAXs but I just don't have that kind of money (~$1000). Since reading through these forums, I am feeling brave and will attempt to make some of my own 3MAX. I have no idea what components Sensaphonics put in their IEMs. I don't want to to take away from Sensaphonics, I think they make world-class products.
 
So here is the plan: After much research I have decided on these things:
 
Things I want to accomplish:

1. use the smallest most hidden shell I can make
2. use a soft silicone (with a pinkish pigment, hidden is the key here)
3. 3-way design accomplished with 4 drivers 
4. I don't want to use filters or dampers
5. give the "sub-woofer" a backspace
6. use my existing sensaphonic shells as the ear impression (they're jelly in my ears, so good)
7. have a detachable cable
8. I grew up in live audio world, so I want to make my 3-way design like that, full rage speaker with an added subwoofer

 
Equipment:

1. Knowles GQ-30783-000 - full range speaker (dual driver)
2. Sonion 3300 - "Sub-Woofer" "also dual driver"

 
Unknown Equipment:
 

1. ??? - for the non-inductive low pass I'm thinking of 75Hz crossover freq
2. Harder pourable silicone - negative impression/mold
3. Super soft platinum silicone - for the new ear shell
4. Pink and red Silicone pigment
5. wire
6. 2-wire jack
7. and IEM cable that has a bendy thing to go up and around the ear with a 2-wire prong

 
I plan on posting pictures and posting info as I go. I would really like any input you have. I have no way of tuning before it's all done, so I'm hoping the full range with the sub is the "done all on paper trick"
 
Other ideas I'm having is using a longer narrower hole for the low end driver, and a short hole with a trumpet-like opening for the full range. I'm not sure about time alignment issues at these distances.
 
Also, I'm going to diagram it all out before anything gets put together, I want to make sure the impedances are right and all that jazz, so I might get higher impedance drivers and wire them in paralell with an in-line low pass to the sub. Fun Times!
 
I want to try to keep all this below $250
 

 

[Nixon]

List of where to buy the parts for custom IEMs. http://www.head-fi.org/t/430688/home-made-iems/945#post_7823930
 
Would advise you to read this thread all the way though before starting, you'll learn a tonne about iem building.

 

[kenman345]

what do you mean by driver? BA or dynamic? I don't really know if a BA driver would benefit that much from the extra air you wanna give it. Mounting a dynamic driver along with BA drivers would be a difficulty you would have to handle.
 
Impression kits are not expensive and may yield a better reference for an impression than those already made from your impressions when making your custom molded shell.
 
Also, a detachable cable wont be hard, if you go with a two pronged setup like Westone and other manufacturers use, then you can get a cheap cable to use and just use that as a template to make the detachable cable section. Shouldnt be too hard.
 
Good luck I guess. Should be interesting to see
Quote:

Hello,
 
So I'm starting a new IEM project, I have desired to have Sensaphonics IEM's for the longest time ever since they made my shells for  the the classic Westone UM1/Shure E1. I really wanted some 3MAXs but I just don't have that kind of money (~$1000). Since reading through these forums, I am feeling brave and will attempt to make some of my own 3MAX. I have no idea what components Sensaphonics put in their IEMs. I don't want to to take away from Sensaphonics, I think they make world-class products.
 
So here is the plan: After much research I have decided on these things:
 
Things I want to accomplish:

1. use the smallest most hidden shell I can make
2. use a soft silicone (with a pinkish pigment, hidden is the key here)
3. 3-way design accomplished with 4 drivers 
4. I don't want to use filters or dampers
5. give the "sub-woofer" a backspace
6. use my existing sensaphonic shells as the ear impression (they're jelly in my ears, so good)
7. have a detachable cable
8. I grew up in live audio world, so I want to make my 3-way design like that, full rage speaker with an added subwoofer

 
Equipment:

1. Knowles GQ-30783-000 - full range speaker (dual driver)
2. Sonion 3300 - "Sub-Woofer" "also dual driver"

 
Unknown Equipment:
 

1. ??? - for the non-inductive low pass I'm thinking of 75Hz crossover freq
2. Harder pourable silicone - negative impression/mold
3. Super soft platinum silicone - for the new ear shell
4. Pink and red Silicone pigment
5. wire
6. 2-wire jack
7. and IEM cable that has a bendy thing to go up and around the ear with a 2-wire prong

 
I plan on posting pictures and posting info as I go. I would really like any input you have. I have no way of tuning before it's all done, so I'm hoping the full range with the sub is the "done all on paper trick"
 
Other ideas I'm having is using a longer narrower hole for the low end driver, and a short hole with a trumpet-like opening for the full range. I'm not sure about time alignment issues at these distances.
 
Also, I'm going to diagram it all out before anything gets put together, I want to make sure the impedances are right and all that jazz, so I might get higher impedance drivers and wire them in paralell with an in-line low pass to the sub. Fun Times!
 
I want to try to keep all this below $250
 

 

 

[tony-pro]

Thank you, although I am looking for suppliers from the states
 
Yes, that is a great thread, I'm about 30% through it and I've been reading it the past 3 days.

 

[tony-pro]

For sure Balanced Armature. It seems like there's a reason for the back port and I thought it was for low-end.
 
Both of those Drivers I listed are BA
 
Quote:

what do you mean by driver? BA or dynamic? I don't really know if a BA driver would benefit that much from the extra air you wanna give it. Mounting a dynamic driver along with BA drivers would be a difficulty you would have to handle.
 
Impression kits are not expensive and may yield a better reference for an impression than those already made from your impressions when making your custom molded shell.
 
Also, a detachable cable wont be hard, if you go with a two pronged setup like Westone and other manufacturers use, then you can get a cheap cable to use and just use that as a template to make the detachable cable section. Shouldnt be too hard.
 
Good luck I guess. Should be interesting to see


 

 

 

[tony-pro]

So I'm finding the prices of medical grade silicone, and pigment, and also the cable to be some of the most expensive parts of this whole thing.

 

[tony-pro]

Anyone know of a low-pass or band pass circuit I could use for this project that does not use an inductor?

 

[tony-pro]

Today I purchased some Medical Grade Silicone.
 
http://www.nusil.com/library/products/MED4-4220P.pdf

 

[notgod]

I beg you in the name of Zarquon to do take photos, and if you can, videos.
High quality silicones of a proper hardness are so much more comfortable than the rocks... I wish you the best of luck in this project, bro!
 
«the smallest most hidden shell I can make» sounds like ACS T3 with a better driver.
 
P.S. Keep in mind that the tube distance significantly changes the frequencies — see this pdf.

 

[tony-pro]

Here's a starter, the pink are my original impressions, the shells fit my old UM1's. and that little BA driver is a Knowles 8507.
 
I will be using some cheap mold material to make the negative. Sensaphonic definitely grinds some stuff out. I don't think I will be using tubes, I want to make a "tube" in the silicone because I want to go with a  damperless design.
 

 

[Fredrichs]

Looks great thus far. Where did you purchase the silicone.

 

[tony-pro]

 
Quote:

Looks great thus far. Where did you purchase the silicone.

 
I got it from Nusil (linked in an above post)
 

 

[tony-pro]

Any circuit people out there to check this diagram?
 
I'm having the crossover point on the sonion at 85Hz and I'm trying to keep the overall impedance at ~30 Ohms
 

 

[tony-pro]

What are peoples thoughts on using wax as the negative mold material?

 

[eric434]

No idea about wax, but what did you use to keep the original casting material from going too far into your ear and getting stuck on the eardrum or something?