Home-Made IEMs
Aug 2, 2017 at 11:57 PM Post #6,736 of 15,974
Has anyone tried a build with a RAB either by itself or with a CL? Also, I'm wondering if you guys could show me how to use the previously suggested crossover calculator here: http://sim.okawa-denshi.jp/en/Fkeisan.htm

I see that if you put in a resistance and capacitance in the calculator it shows whats the cutoff frequency. However, doesn't the impedance of the drivers also play a part?
 
Aug 3, 2017 at 12:37 AM Post #6,737 of 15,974
Tranhieu, I was thinking about doing the same thing for my next pair, did you do a wax impression and then cast the silver ? I tried to do a sand casting but could not part halves without damaging the mold.
Yes I did, we need the wax for some proper buildup. Metal shrinks a lot after cooling down.
 
Aug 3, 2017 at 12:17 PM Post #6,738 of 15,974
Yes I did, we need the wax for some proper buildup. Metal shrinks a lot after cooling down.
Thats Awsome, I would live to see a photo of your setup. Did you use a plaster cast or delft clay mold ? How did you cast the interior void and tube channel ? I was thinking about just casting it solid and then milling out the interior, but have not figured out the tube channels yet.
 
Aug 4, 2017 at 1:20 PM Post #6,739 of 15,974
Hi guys, I'm new so first I wanna thank everyone for all the information you guys put in here, really really good stuff.

I'm planning doing 2 CIEM and I have some questions that if someone could help me it would be awesome. (I already searched and I didn't find the exactly answers, but if someone has already spoken about this I'm sorry for asking again)

First one is: how can I make an negative mold that last "forever"? because I wanna make a master mold of my impressions first, so I can cut later and don't worry about ruining the original, since it's my first time doing that, and I can't afford making another impression right now.

For the final negative mold I'm thinking about using gelatin or some duplicater material called k-27 that I found here in brazil, I believe its some type of hydrocolloid, but from what I've read, none of these hold the form more than one week. :frowning2:

Maybe the best option is making a negative, then a positive with silicone or (?) so I can cut these and not the original impression?

Regarding drivers I'm thinking about using the CI-22955 for a one driver CIEM (not sure yet), and GK for a triple driver, mainly because I don't fully understand crossovers wiring and etc.. so these are ready to go, just weld the cable adapter wires and it's ready, right?

If anyone have some cheap alternative to the drivers, like taobao or something.. it would help a lot, because shipping to brazil is very expensive and we don't have a knowles reseller here I believe.

What dampers should I use for those drivers? I'm going to use the CIEMs in live shows for monitoring/mixing and listen to music on my phone.

Sorry for the big post, thanks!
 
Aug 4, 2017 at 8:49 PM Post #6,740 of 15,974
Hi guys, I'm new so first I wanna thank everyone for all the information you guys put in here, really really good stuff.

I'm planning doing 2 CIEM and I have some questions that if someone could help me it would be awesome. (I already searched and I didn't find the exactly answers, but if someone has already spoken about this I'm sorry for asking again)

First one is: how can I make an negative mold that last "forever"? because I wanna make a master mold of my impressions first, so I can cut later and don't worry about ruining the original, since it's my first time doing that, and I can't afford making another impression right now.

For the final negative mold I'm thinking about using gelatin or some duplicater material called k-27 that I found here in brazil, I believe its some type of hydrocolloid, but from what I've read, none of these hold the form more than one week. :frowning2:

Maybe the best option is making a negative, then a positive with silicone or (?) so I can cut these and not the original impression?

Use Wax to make a negative mold of the impression. Then make more ear impressions into the negative wax mold. Note that you will need to drill a small hole to vent out the ear canal. Also dont use the foam stopper.
For your final negative mold, if you want a long lasting one you need silicone duplicating material, for Dreve it is called Fotosil. I wouldnt bother with this if your budget has limits, just make a master positive mold out of acrylic and cast a new negative each time.
 
Aug 5, 2017 at 4:47 AM Post #6,741 of 15,974
Do you guys have problems matching DWFK with HODVTEC and SONION 38am007m/8a? I'm having some phase cancellations as soon as I connect it. Tried everything from switching polarity to changing HPF values towards more mid high on the DWFK but nothing seems to works. I'm using 2nd order xo. Any ideas what might be causing this?
 
Aug 5, 2017 at 12:59 PM Post #6,742 of 15,974
Thats Awsome, I would live to see a photo of your setup. Did you use a plaster cast or delft clay mold ? How did you cast the interior void and tube channel ? I was thinking about just casting it solid and then milling out the interior, but have not figured out the tube channels yet.

I'm not sure about the specifics since I have my jewelry craftman friend made them for me. But he cast the hollow shells right off the bat so no milling at all.
 
Aug 6, 2017 at 9:04 AM Post #6,744 of 15,974
Time to start it up. I am starting my CIEM business~ Will launch the website within a month time.
https://www.head-fi.org/threads/elysian-acoustic-labs-1st-malaysian-ciem.857162/
mUBHdzJ.jpg
congrats! ...but you might want to read head-fi TOS
 
Aug 7, 2017 at 2:57 PM Post #6,745 of 15,974
Hey guys, I made a pair of quads for a friend of mine a couple months back (Knowles GV) and he told me yesterday that he thinks his left ear is going out. But the way he described it I don't think it's losing connection and just stopping altogether. He said he thinks it is gradually getting worse over time? He uses them all the time caus he makes his living playing bass. He also said that he doesn't think he blew the speakers cause he's cautious about never going over half volume. So I'm just at a loss...
Have any of you guys ever experienced anything like that?
Also, do any of you guys have a good way that you get faceplates back off? Cause I'm dreading that!! I want to salvage the faceplate if I can at all obviously.
Thanks!
 
Aug 8, 2017 at 2:12 AM Post #6,746 of 15,974
Hey guys, I made a pair of quads for a friend of mine a couple months back (Knowles GV) and he told me yesterday that he thinks his left ear is going out. But the way he described it I don't think it's losing connection and just stopping altogether. He said he thinks it is gradually getting worse over time? He uses them all the time caus he makes his living playing bass. He also said that he doesn't think he blew the speakers cause he's cautious about never going over half volume. So I'm just at a loss...
Have any of you guys ever experienced anything like that?
Also, do any of you guys have a good way that you get faceplates back off? Cause I'm dreading that!! I want to salvage the faceplate if I can at all obviously.
Thanks!
1st check for earwax. it might be the problem.

2nd it might be the tubing detaching itself from the driver.

3rd getting the FP is tricky it depends if you glued it (maybe wood plate) or if it's all acrylic.
If you need to keep the FP and cannot take it apart you should use the CIEM to make an investment out of it so you can make a new shell and then you could break the body shell on the original making sure you can use everything without damaging the plate.

You'll need a cutting wheel (use it the less) and some sharp small pliers (use this the most as it is easier to control and cut the acrylic)
 
Aug 8, 2017 at 12:55 PM Post #6,747 of 15,974
Hey guys, I made a pair of quads for a friend of mine a couple months back (Knowles GV) and he told me yesterday that he thinks his left ear is going out. But the way he described it I don't think it's losing connection and just stopping altogether. He said he thinks it is gradually getting worse over time? He uses them all the time caus he makes his living playing bass. He also said that he doesn't think he blew the speakers cause he's cautious about never going over half volume. So I'm just at a loss...
Have any of you guys ever experienced anything like that?
Also, do any of you guys have a good way that you get faceplates back off? Cause I'm dreading that!! I want to salvage the faceplate if I can at all obviously.
Thanks!

Basically what ForceMajeure said.
If the driver inside is vented, do not cut as the dust can get into the holes. Use a small to medium size pliers. Put it over the ear canal part and carefully crush/break it, don't use much force it is very easy to crush that section (assuming it has more than one bore, otherwise start higher up near the base of the canal where it is hollow), make sure there are no drivers where you are crushing, dampers will survive as long as you don't overdue it. Once that is complete you can begin to slowly crush and peel away the shell piece by piece carefully. Once enough of the shell is gone you can remove the components. Then you can take the remaining shell with the faceplate and sand off the shell part to preserve the faceplate. It's easier than it sounds.
 
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Aug 9, 2017 at 6:36 AM Post #6,748 of 15,974
Has anyone tried a build with a RAB either by itself or with a CL? Also, I'm wondering if you guys could show me how to use the previously suggested crossover calculator here: http://sim.okawa-denshi.jp/en/Fkeisan.htm

I see that if you put in a resistance and capacitance in the calculator it shows whats the cutoff frequency. However, doesn't the impedance of the drivers also play a part?

I actually made a ghetto DIY with the RAB 32257 recently. The goal was to just make something that was tiny and can be worn comfortably to sleep, but it turned out to have surprisingly good sound quality (decent bass, mids, detail, and soundstage that I didn't expect from a 1BA setup). No dampers or electrical crossovers of any sort was used, it was just wired direct and tucked under 2 layers of heatshrink and glued into repurposed metal bores. As with most BAs, you really want to ensure a perfect seal. Also, rumours have it the Etymotic ER4XR also uses the RABs with a green damper. It's probably the best and simplest single BA solution if you can't fit a pre-made dual (GU/GV) or a triple (GK).

7c75016c-5718-4262-b359-2391c737c361.jpg

I'm actually going to attempt a 3-way (with doubled drivers) with the 32257s as mid/full-range drivers, would love any advice and suggestions. Can probably only put together and test 2 months later, though.

Planned set-up is
Lows: 2xCI with yellow dampers, probably gonna stick a 10-20 ohm on them. Might RC low-pass one of them using Piotr's 75Hz design. Should I wire these in reverse polarity?
Mids/full: 2xRAB grey/white/brown dampers. Probably not gonna RC filter them...
Highs: 2xTWFK or 2xSWFK(32255, with peaks shifted and tamed) or 1xTWFK+1xSWFK, brown dampers. If TWFK: usual 1uF on the FK, 22uF on the WBFK for high-pass? If SWFK: just 1uF on one/both FKs? (I've never had a chance to play with SWFKs yet, though)

I've got almost all regular cap values up to 47uF
 
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Aug 11, 2017 at 5:34 PM Post #6,749 of 15,974
Hi,

Which Dampers are you using with the Knowles GV driver?
I was using 1500 for TWFK and 3300 for HODVTEC and I tried without dampers.
I only have the the Samsung galaxy s7 as player. But soon I want to buy maybe the fiio x3.
The bass is really weak, comes from the s7.. hab not enough power? This will be getting better with maybe the fiio x3?
Rest of the sound is really nice and better than everything I heard before.
 
Aug 11, 2017 at 9:32 PM Post #6,750 of 15,974
Hi,

Which Dampers are you using with the Knowles GV driver?
I was using 1500 for TWFK and 3300 for HODVTEC and I tried without dampers.
I only have the the Samsung galaxy s7 as player. But soon I want to buy maybe the fiio x3.
The bass is really weak, comes from the s7.. hab not enough power? This will be getting better with maybe the fiio x3?
Rest of the sound is really nice and better than everything I heard before.

That's strange. I don't think it's a problem with the S7 (I have it too, and it's a very capable player for most IEMs). Did you check that the drivers are properly sealed, spout-to-eartip?
 

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