CHANGSTAR: Audiophile Headphone Reviews and Early 90s Style BBS
Lobby => DIY => Topic started by: AstralStorm on June 27, 2013, 12:08:34 AM
-
(http://pressbox.co.uk/images/logos/749046_PIRATE%20HACK.jpg)
SCIENCE! (http://www.youtube.com/watch?v=V83JR2IoI8k)
Also shameless plug: Hackerspace Warsaw (https://hackerspace.pl/about_en) & Gallery (https://gallery.hackerspace.pl/)
I'm about to endeavour into making a custom IEM from grounds up, starting with ear impressions, through design, tuning to damping and maybe even measurements.
The whole idea is to make the most neutral yet musical IEM possible.
Also mess up horribly and spend lots of cash. (I bet I could buy about 2 ready-made TOTL CIEMs for this.)
Hopefully no electrocution will be involved this time - fortunately, last time it wasn't me being zapped.
Current plans involve:
1) Ear impression materials and tools - in progress, thanks to Corey
2) VSonic GR07 for a neutral dynamic driver CIEM experiment - ordered
3) 100% silicone with citric acid (medical) - acetic acid is smelly, but in a pinch could be used
4) Silicone caulk with gypsum (need pure gypsum and have to find the right proportion)
5) Custom tips for IEMs - Sony MH1, Hifiman RE-ZERO and RE-600 - to test the impression and molding process
6) Hacky 3D scanner to digitize the impression - to be done this weekend
7) Sonion 2354 tweeter armatures for neutral 4-way BA CIEM experiment
(The other two are Knowles TWFK and Sonion 26A005/8, which I already have. TWFK counts as two, the FK will be useful for bass.)
8) Silicone tubing - have some 4/6mm tubing as well as 2/4mm. Might need even smaller, e.g. 1/2mm.
9) Detailed crossover design for the BA CIEM
Optional further ideas:
A) PMA (polymethylacrylate) elastomer inserts - faux leather
B) UV printed acrylic shell
C) Using different 3D printing stock from ABS (e.g. PP - polypropylene)
D) Replaceable cables, probably Westone sockets
The choice for dynamic driver experiment is VSonic GR07's driver, because it's reasonably neutral and mostly hampered by the not that great, mostly undampened shell and too narrow nozzle. This driver is also nicely protected against likely mishandling. (Yes, I've killed a few IEMs while taking them apart. The membranes are easily damaged.)
Interior will be dampened, most likely with cotton, but perhaps glass wool. I also considering sourcing some Kapok cotton and silk.
This driver doesn't really require any venting.
The BA CIEM will have an external crossover unit for ease of tweaking and building, kinda like UM PP6. I'll try to use lowest values possible, probably 3+3rd order Butterworth for good phase linearity and excellent frequency response. Alternatively Linkwitz, 2nd order.
I'll try first order too, but I suspect that this will cause some interactions.
Current idea of this setup involves using both FK and Sonion-low (26A005/8) as bass drivers and mids drivers, WFK and Sonion-high (2354) as highs driver. The crossovers will be probably placed at 6 kHz (FK/WFK - B2 uses default 4.5, this might be good too if I cross Sonion-high lower) and 5k or 8 kHz (Sonion-high), 3rd order Butterworth likely. Sonion-low (26A005/8) will be running full range.
Resulting impedance should be relatively low, around 20-50 Ohm, and flattish, similarly phase response. High sensitivity. The peak/dip pattern falls such that the drivers mostly complement each other.
If it becomes necessary, I'll also have Knowles dampers, but I'd rather not resort to them.
Venting shouldn't be necessary here really - even the Sonion drivers don't need it really unless they're used as a sole bass driver.
Tubing layout is not determined yet.
The armatures in question all have a different wideband sound: Sonion-low is warm smooth sounding, Sonion-high is sharp and coldish, FK is quite sharp while WFK is nicely smooth. Properly blended, this should give a neutral timbre.
I will either get a measurement microphone and jury-rig a measurement setup, send them to Anax/purrin for measurement, or both once I'm happy with the sound.
Starting a production line is not really planned, but I might do a one-off request, who knows.
Datasheets of the BAs:
Sonion 26A005/8 (http://www.sonion.com/Products/Transducers/Receivers/~/media/Files/Products/Data%20Sheets/Transducers/Receivers/Receivers%202600/Receiver%202600/26A005-8_v3.ashx)
Sonion 2354 (http://www.sonion.com/Products/Transducers/Receivers/~/media/Files/Products/Data%20Sheets/Transducers/Receivers/Receivers%202300/Receiver%202300/2354_v2.ashx)
Knowles TWFK (http://www.knowles.com/search/prods_pdf/TWFK-30017-000.pdf)
Visual ear impression and insert manufacture instructions (for those who can't understand Polish; there are some descriptions for others) are here:
http://www.ia.amu.edu.pl/index.php?option=com_content&view=article&id=76&Itemid=16
Compared to this lab, my gear will be better in a few ways and worse in others. For example, I don't have a dryer, "gel machine" and pressurized equipment, but instead I will have many more kinds of lacquer and grease, lots of cyanoacrylate glue, various solvents, better mechanical tools.
-
Reserved for future use. Do not swallow.
-
In terms of the dynamic, could a very small vent be added to give better subbass and bass energy? How does that effect the dampening system you'll use?
Also, a vent lets the diaphragm move fully, I was told by a Future Sonics tech, but I'm just parroting that because I'd like to hear your feelings on it.
-
Yes, a vent will prevent overpressurization - but that shouldn't be an issue. Most of the time, a vent acts as a resonator, depending on placement and size, anywhere in 0.1 kHz to 8 kHz range.
Original VSonic GR07 is vented, but I've found that closing the vents, esp. the front one, reduces its bass boost to neutral levels with no adverse effects, as the cellulose driver itself is not sensitive to ear canal impedance, insertion depth or pressure.
Stock venting is clearly designed to enhance bass response - which doesn't need to be enhanced really.
Damping material further reduces the need for venting to maintain subbass response by making the apparent air volume larger - slower speed of sound in the damping medium.
-
Interesting. Will you further mess with the shape of the space around the driver to tune it?
Also, will it be like a custom-shell with universal fit design or custom-fit because damn, you'll get yourself a little market for your experiment here, I'll bet. I'll pony up for one. Looking forward to seeing how the dynamic and ba designs turn out.
How about a hybrid?
-
The starting ones will be fully custom, since I'm making it for myself, like any
respectable insane scientist should. I might build more of course just to see if I can reproduce it.
The 3D printed variant will be simple to adapt and reshell.
Silicone one, well... The dynamic driver one might be especially tricky. Essentially have to do-over the whole IEM. It's not impossible to have a silicone universal though.
Hybrids are overrated in my opinion - a single dynamic driver can do everything a set of BAs can, except being small and easy to install. And perhaps resilient against moisture. In fact, they excel at distortion and some also at decay - and they beat most BA setups at high end extension. Plus there are no crossovers and fewer parts to mess with. Therefore, combining a BA with a dynamic driver would only be useful to shape the frequency response at the cost of added distortion of the armature if it cannot be achieved in a cheaper and simpler way.
Not to mention the BA will be somewhere in the way of the pressure wave, distorting it and causing reflections - messing up the highest end further.
However, BA are easier on QC, since all parts are testable separately. Plus the small size and no need for a resonant chamber is sometimes huge.
The other way around, adding a bass dynamic driver to BAs, is not a good idea - in bass, neither a small dynamic driver nor proper BA is superior, except perhaps at air movement - which can be solved by tossing more BAs at the problem.
I will of course tweak the resonant cavity if necessary. For a dynamic of this size and Qts, I'll need an apparent volume of 1.5 cm^3, which is about 2.5x the original one. It's not huge, like with Hifiman weird older drivers. (RE-ZERO, RE-0, RE-2xx series)
-
Huh, thanks for explaining.
It's weird that vsonic didn't use a large enough shell and you mentioned that this was part of the 7k spike they have.
Anyway, it'll be very interesting and I hope you'll let people send you gr07's and some cash as things go along. You can always have a set number you'd like to make (put me on the list!).
Too bad there's not a way to source the re-272 driver and give it some subbass...
-
A question, and might be silly: wouldn't the GR07 not sound like a GR07 if you take away the shell and the narrow nozzle? I'm only basing this on only my experience with mildly modding my T50RP and changing IEM eartips. Since even changing eartips does change the overall sound a bit at the very least, won't something larger like taking out the GR07 driver out of its shell change the sound drastically?
-
They will sound like GR07. I've actually shortly tested a transplant into dampened Brainwavz M2 shells, which worked beautifully and actually improved both sound and fit.
Unfortunately, an accident happened while removing one of the drivers and I broke the membrane in one channel. (my plastic screwdriver has slipped)
-
Extremely ambitious. Good luck AS! I wish I could get hold of a 3D printer
-
3D printers range from cheap to extremely expensive. Decent small one can be bought for less than $800 in a kit form, all parts, ready to be assembled or even fully assembled. I won't be endorsing any of the specific shops as there are quite a few. Complete kits can even be bought off fleabay, even cheaper.
The tricky part is sourcing ABS filament at decent prices.
-
Ahh, so my understanding is wrong.
Either way, godspeed on your project. This is going to be interesting.
-
3D printers range from cheap to extremely expensive. Decent small one can be bought for less than $800 in a kit form, all parts, ready to be assembled or even fully assembled. I won't be endorsing any of the specific shops as there are quite a few. Complete kits can even be bought off fleabay, even cheaper.
The tricky part is sourcing ABS filament at decent prices.
For the interested, Kickstarter does have lots of printers for small form factors at very affordable prices. Though one has to wait for a long time. Anyways, great to see a project like this hear, good luck!
-
Have a look at my threads on HF, you might find something useful.
http://www.head-fi.org/t/616728/ciem-digital-manufacturing-hybrid-iem
http://www.head-fi.org/t/661952/diy-custom-in-ear-monitor-information-resource
Cheap 3D printers , I am not sure of accuracy of them and if they will be able to print shells of 0.2 to 0.5mm with undercuts.Easier way would be to use manual method and UV curing.
For Dynamic driver you will need to have exact same enclosure so as to produce same tuning. DD can be tuned by air volume on back and front of drivers.
-
Yes, they will easily be able to handle such small smooth undercuts in a smooth shape like an impression.
I will slightly retune GR07's driver, since I know how to improve on the original tuning - which is quite good already.
-
Ok, real life contravened the 3D scanner implementation. Have to order a camera with the right focusing length and preferably zoom, that's also controllable from computer.
Alternatively, need one extra stepper for the depth.
The idea is to use focus information to detect the depth and "just about sharp" pixels, for starters with a small reasonably high strength central difference filter, but perhaps some better edge detector later.
The camera needs short focus depth and very low depth of field. For f = 38mm, f/1.4 would be appropriate for 1mm resolution, but I need something better. Larger zoom lens that is.
I'll ask around in the camera thread.
The alternative is to use the grid projection, but it has one drawback - cannot capture color.
-
Project continues. I hear the required impression materials are soon to arrive, meaning week or two.
In the meantime, I'll have some Sugru to experiment this weekend. We're running a bit of experiment and some Instructables.
Mine will be about shallow/medium fit impressions and perhaps a universal but customized ear tip as well.
3D scanner project will be resurrected using a dynamic grid or interference scanning too, also this weekend and later.
Measurement microphone is also near, should get out of customs office momentarily.
Calibrated Dayton Audio EMM-6, real cheap and supposedly better than "staple" Behringer ECM8000, see Parts Express.
I do have proper recording hardware with phantom power.
However, what I don't have is a real coupler, so I'll improvise using a silicone tubing of correct volume. Later perhaps my own ear canal negative mold.
One of the molds will probably be an ear and cheek simulator - but that later. For now, IEMs.
Pics of the setup will be coming.
Mold making materials - acrylic, silicone, silicone tenderizer, mold release etc. have been ordered as well, should arrive next week.
-
Don't get anything stuck in your ears! :)p13
Looking forward to the next installment, with pictures! :)p7
-
Also received GR07 Flagship edition.
Better tip selection thanks to foamhybrids, but none of these are still suitable for deep insertion. Best results with Hifiman long biflanges with "gap" between the flanges or with Hifiman small biflanges. Both ar a tiny bit too large, need to be pushed past the stopper and are just clutch fit on the IEM.
Annoying to audible 6.3k ringing (depending on depth) and some boost giving an edge to the sound, bit subbass drop, reduced air, but it seems they did something there to the shell, sound is less bassy and more airy than I remember. It's a minor but good change. It also is silver and looks and feels thicker. I'll let it live for some time in normal form.
So it's likely the patented nozzles are the source of their ringing or the thick metal meshes in them.
Kinda a real difference after all the Hifimans and especially minor modded Sony MH1 which are nearly linear and excellent fidelity. (and possible to improve yet more I think.)
5 years... they sound outdated nowadays. I'll try to make them shine, the issues are related to both shell and fit much more than the driver.
Pics will be incoming on weekend assuming Sugru® experiment will pan out. And even if it won't.
A friend apparently has some molding silicone left from another project too, so I might be able to create the measurement negative.
-
AS, would you say a different, more recent driver might be more technically capable?
I have been told part of the price with higher end dynamic driver earphones, such as the monster turbine copper/gold for example, is simply that they sort through the normal turbine drivers they have and naturally some perform better than others. They take the top 10%, match them better than usual, and give better cables, etc. At least, that was what I was told by Grandpa Karth a few years back.
Would you say that's still the case, more or less?
Are newer dynamics giving better quality at lower prices than they did a few years back?
-
I'm not entirely sure, GR07's driver is no slouch, it's the shell that is problematic - and the recommended very deep fit.
Hifiman drivers are better, but it seems to be impossible to remove them from their shell without damage - I don't know how to do that, I've tried numerous times.
Those are glued in by the annoying chinese hotglue, without any protective metal casing.
MTPG/MTPC is probably not really better, it doesn't have the detailing, but might be there's something to be done about it. They are only improved matching versions of Turbines.
Sennheiser IE8 driver is better, Hifiman RE-272 driver is too. IE800 driver might be a bit better as well. Same might go for RE600, which I haven't heard yet.
See, 50% of the work at a dynamic driver IEM is in shell and tuning via filters and venting. This is where GR07 fails, not at the excellent driver. It's easy to check - just remove back of the shell and hear a major improvement already. It's possible that newer VCO2 can be improved considerably too by modding the shell.
The ringing at 6.3k is nicely reduced with the eq as well, but not completely eliminated. Bass still sounds bit choked (too short decay at lowest parts) despite correct volume - the driver is struggling in a too small shell or the lack of perfect fit causes this issue.
Note the difference between shallower but good fit and deeper but "clutch" almost fit. The seal means the bass sounds much better (still slightly choked due to limited chamber size) and no need of bass adjustment means I can use the spare parametric at the highest end. Plus the deeper eq cut at 6.3k means ringing is yet more reduced, still bit audible though. W/o eq the shallower fit sounds atrocious though due to that peak.
These are way better driven by the Leckerton than FP10 for some reason, perhaps smoother treble.
-
Very interesting, thanks!
Too bad about the hifiman drivers. I wonder if the re-400 is put together the same way?
-
Unfortunately it is. I need to figure out some gentle way to unbond this kind of glue without ungluing the membrane from the driver, some time later.
-
Yeah its nearly impossible to remove such drivers without damage. I have tried a few without any success. Drivers like IE8 , Monster are much easier to work with as they have metal shell and also mesh on front to protect the membrane.
-
The good news is though that this doesn't preclude the use of RE-400 in a custom shell, just making the ear canal part and nozzle smaller than ~4mm. Nor does this preclude the making of custom tips.
One can open the back easily, unlike RE0/RE-ZERO, unsolder the wires (carefully at lowest temperature possible!, I've ruined enough drivers this way by unsoldering driver coil accidentally), remove the back and strain relief and solder a cable back in. I will do such a trick for RE-600 once that's available - it uses the same small shell.
Such an approach works for all small IEMs.
It does not work for RE-252/262/272 with its large "ergonomic" shell - and those IEMs benefit from deeper insertion too, much like RE-400 and presumably RE-600, unlike RE-ZERO/RE0.
-
A fine day of hacking.
(http://wstaw.org/m/2013/07/14/FU9160_PIRATE_HOOK_jpg_300x300_q85.jpg)
It seems that Sugru is not suitable for impressions without an audiological syringe - the material is too stiff.
The result is in the attachment. I've used cotton "ghetto" otoblocks put in and removed manually using a microchip flat small tweezers.
Also made the cinch/jack "balanced" cables. Technically the cable topology is wrong, as the "ground" goes as screen and is not a twisted pair, but that's not a true prerequisite, just nice to have. That black thing near the jacks is Sugru as well - used it instead of electric tape and shrink wrap isolation. Much, much nicer to work with.
The molding silicone, polyurethane and acrylic materials are also pictured. I'll use them as soon as I'm able to make real impressions of decent depth.
-
The measurement microphone has arrived, Dayton Audio EMM-6. Pretty swanky for cheap $50 stuff. Its main drawbacks are somewhat low sensitivity and low SNR.
This means it's not really suitable for recording convolution reverbs or measuring jitter, THD and IMD.
For other intents and purposes, like CSDs and FR, it's very workable.
It is calibrated with the data available on their website after typing in the serial number.
This microphone will be crucial in evaluating the IEMs and headphones.
Also included a sturdy PET case for carrying the mike. Not that you'd really want to - it needs a beefy amplifier with phantom power.
Also got an extra lapel ATH ATR3350 battery biased electret omni for chatting.
Now I own 3 microphones: one measurement electret omni, one lapel electret omni with phantom power, one dynamic vocal Shure PG48.
Have a sample using the measurement omni in my echoey room, mike was also pretty far, so I had to amplify quite a bit and denoise.
-36 dB noise floor, but those modern denoising algorithms are great.
The other one is recorded using the lapel mike, pretty decently sensitive, still omni. It's actually stereo even. Some denoise never hurts though, getting -60 dB SNR or so.
Please fix the board to allow more filetypes, zipping everything gets old...
Note to self: build a rig that will seal headphones - unsealed measurements mean 0 damping.
Note 2: The measurement microphone is actually low impedance, unlike the lapel one - it goes into a low Z socket and then is extremely clean, as in the cleanest of the bunch, especially if the wind shield is put on, as it attenuates high frequency noise. The microphone is within +/-2.5 dB of flat without correction. Attached the downloaded calibration data.
-
Good luck with your project Astral.
Yes I mean it. =]
Finally an interesting thread to read on this site.
Do you have any pictures of the GR07 driver? I was thinking about breaking mine as well to put in a CIEM with ED-29689.
I like the bass tone and speed of the GR07 driver, much more than for instance 2x DTEC.
I may also consider GR07 bass + DTEC mids + TWFK highs? Lol. =D
-
Finally an interesting thread to read on this site.
Glad you're enjoying your time here... :-Z
-
I will take it apart and show the easy to handle construction.
Again, it's the shell that is subpar due to back reflection and too small Vas.
The vents help, but are not enough.
If making a hybrid, I'd use the Sonion 23xx tweeter (mentioned earlier) and slightly overdampen the dynamic to reduce the 6k edge and its slightly grainy highs. Toss in a cap parallel to the tweeter to reroute bass. 5k 1st order crossover.
TWFK shares the peak, so is not a good match, while that ED doesn't have enough extension to help.
I'm looking for a good source for Sonion armatures. However, GR07 will be a dynamic only custom at first.
Still waiting on the shipment of impression material.
-
The ED has pretty good extension in the ER-4, so you think the Sonion tweeters have better extension?
I'm not going to make it myself, I don't have access to a "hacker lab" like you, I'm basically just telling a CIEM designer what I want ^^
Sooooo what colour is the GR07 driver? Like this? http://cdn.head-fi.org/d/d7/1000x500px-LL-d7c1fc31_GR-07Driver.png
You could use a resistor on the outside of the CIEM, it's a cool idea! http://www.barks.jp/gakki/news/?id=1000079454
(http://img.barks.jp/image/review/1000079454/003.jpg)
-
There is one Sonion tweeter doing to 20 kHz and another to 19k. The specs are available on site. This ED does 17k and is more of a midrange and low highs driver. Good for a 3-way.
GR07 driver is indeed encased in a bronze or brass case. Super light cellulose.
About the crossover design, I will rather put it in the box on the cable for ease of modification, making it also possible to run an active design or a digital one. The multi BA will use these Sonions in the first post, perhaps with a Knowles CI bass driver, the best one there is for BA, and TWFK for upper midrange and upper bass. 4-way, but a cross like a 5-way to avoid resonant regions. Trying to avoid any use of dampers as well.
WBFK + 2354 highs, some 2354 + FK + 26A005/8 mids, 26A005/8 + some FK + CI bass, 26A005/8 + CI subbass.
The resonances complement each other. Smooth Bessel crosses should do, perhaps with some phase alignment tricks.
I will be able to keep the size small by that abovementioned trick. Remember I am working in silicone, as I don't have Loctite or the UV dryer. That might follow later.
3D scanning as well, so I will be able to make shells in ABS and maybe PVC, PP or PU.
I also want to experiment in making a soft PU and silicone foam CIEM.
-
I remember reading some notes about using crossover components as close as possible to drivers.
2354 is vented ,I guess you cannot use it in Silicone.
For mid range you can use 1700 headspace is good.
You will have to use dampers to smooth the peaks.
-
The venting is for bass response. It is not strictly required, especially not for the use as a tweeter.
Plus you can vent in silicone too, it is just harder to lay out the tubes or drill the holes than in acrylic.
No need to front dampen, as the crossovers will be designed to reduce the peaks, plus the FR complement each other.
The custom GR07 will be vented, just like FutureSonic Ear Monitors, combined with damping, likely cotton.
-
Here's one VSonic experiment. Nicely linearizes them by shifting resonances down a lot. Plus it makes them fit very well and look ridiculous in ears, like Frankenstein monster's bolts.
The shifted resonances nicely linearize 1k - 3k region with slight bump at 4k. (And they're not at the annoying 6.5k ear canal resonance.) About 3 dB differences.
Bass response is also shifted down, while extreme highs extension is a bit improved.
Sensitivity is reduced 12 dB or so. (toggling 4x gain on UHA-6 gives same loudness)
The tips feel better in the ear for some reason, perhaps because now I don't get to jam them super deep and they fit precisely on the first bend. Not like a silicone CIEM, but still very good.
How to make these hacked tips? Jam a 2 cm long silicone 4mm tube down Hifiman long tips using tweezers, making it into a long tip with 1 cm stem and internal diameter 1mm smaller. (It's 4mm, GR07 is made for 3mm tips but can hold some 4mm too.)
This makes me yet more hopeful for the CIEM experiment and custom tips with these.
--
I will be sculpting and building an ear-and-cheek attachment for the measurement microphone (with some sculpted ear canal) and trying out a new excellent silicone foam process. That foam has interesting properties:
- hard until the last step, making for machining as in pure silicone
- flows exactly like pure silicone
- open cell, but not a huge lot
- soft with some memory but mechanically resistant - softer than Shure olives, firmer than Comply (will check with various source silicone; this is with one generic junk)
- smooth surface
- shock resistance and low resonance, usable for a damping material
- no need for annoying gas tanks or toxic, smelly solvents
The main drawback is that the process requires a full crosslinking step. (When it's machine-able.) Me and a friend will be trying to optimize it to not have to wait 24 h and dry it some more afterwards.
This will be an interesting material to make a CIEM and tips in.
-
So the ear impression hardware has arrived. It's enough for a year of daily ear impressions for one person, or so.
Contents include: DS-50 gun, 2x CIC impression syringes, box of 30 Siemens Silhouette singlets, 2x QuickCast DS-50 cartridges, box of Westone SiliClone (medium?) DS-50 cartridges (x8), Silicoat lacquer, small DS-50 mixing tips x10, medium DS-50 mixing tips (lots), small (gray, x50) and medium (white, x50) foam stops.
Also related: 2x EtyPlugs (NRR 12; actually 18 dB atten.), various Knowles dampers (white, gray, red, green, orange AFAIR)
And one lithium battery quick checker as a gift for the interesting way of sending stuff by the guy I was ordering from.
I've had my first shot at self-made ear impressions yesterday and today.
I'll describe the processes in more detail later, once I'm fully comfortable with them.
Haven't tested the gun method yet - I want to work out the kinks with the usual syringe method.
For now, some tips:
- Insert foam stop until the abrasion starts to be noticeable and slightly uncomfortable. That means it's past the second bend.
- If the impression is right, the end of ear canal part should be smooth, not pitted like skin.
- Do not skimp on impression material - the right amount is a bit more than half of the singlet for me ~32 ml of the mixed mass for me. Using a whole is fine, you can't reuse it anyway as even without mixing it will harden in air too fast for even the second impression.
- Keep it longer than the instructions indicate. Best until it stops "popping" or "foaming" noises - that means the silicone has stopped expanding and probably vulcanizing. With these Siemens Silhouette singlets, it takes about 4 minutes.
- It is hard to control the nozzle of the syringe while doing it yourself without a mirror. I didn't use one actually for these, but it should help.
- Get a small endoscope to place the foam stops correctly - USB endoscopes are cheap and available on eBay. I didn't get one either.
- Get all 3 sizes of foam stops - you never know... My left ear needs small, right ear needs large - even medium one leaked a bit.
- A small leak beyond the foam stop is not a cause for alarm - but it does waste material and makes for slightly shorter impression.
- I felt a bit of nausea after taking one of the impressions - it's either its silicone oil content or more likely a vagus nerve (http://en.wikipedia.org/wiki/Vagus_nerve) reaction. No cause for alarm. Technically, you could even temporarily fall unconscious (syncope) from it - which isn't harmful either unless it happens a lot, but will mess up the impression. The other more severe possibility is always a terrible allergic reaction, but odds of that are very low.
- In a pinch, you could use a fast platinum cure silicone like Smooth-On MoldStar 15 Fast, but in that case, it is essential that the foam stop fits perfectly, as those are less viscuous and softer, plus it takes 10-15 minutes to cure instead of 3 minutes. I haven't tried yet, first need to get perfect results with normal stuff.
- Do not press the impression while taking it. Smoothing out the surface is not really possible anyway without applying lots of pressure with these singlets - but if you tried, you'd distort the outer ear part and possibly ear canal too. The material can always be added to the back to smooth it out.
And now, the pictures - I cannot take pics yet of the process, for that you'll have to wait until later today, Friday or Saturday.
The left one used a whole singlet, right one was an experiment using 50% of the singlet. Both are respectable, but right one could use slightly more material indeed - there are slight non-critical pits in the outer ear part.
I'll also try to smooth them out and protect the impressions with lacquer later today. Perhaps even make the negative mold.
[EDIT: Forum and/or web browsers do not understand EXIF rotation, so everything is flipped. I'll fix it later.]
-
Another fine day of hacking.
Highlights: learned to use the mechanical impression gun, figured out how to make a negative properly, figured out tube routing (but not tried yet).
Another round of silicone foam experiments - previous were a failure probably due to gloves containing sulphur.
Lots of practice on placing foam stops - now no leaks.
Thoughts and hints:
- Impression material makes a huge difference. Warner Tech-care Quick-Pro ("Clear" color) is the worst. Out of 4 impressions, all had major flaws. I think it is too viscuous and rips while applying due to sticking to the gun. Siemens Silhouette singlets are tricky to use - have to mix it very fast and apply, tends to harden too quickly in the syringe. Usually leaves tiny "fold" artifacts as it is slightly too viscuous when applying. (Blue color) Westone SiliClone is the best. Both impressions made with it were perfect and it is very efficient to boot. I think like Silhouettes it also expands, but is less viscuous. (Pink Color)
- You have to lacquer or apply release compound for silicone-silicone mold - that wasn't indicated in Smooth-On Mold Star 16 Fast instructions. Wasted one pair of impressions on this.
- The foam stop has to be placed uncomfortably deep and getting the end of the syringe there is notably painful and uncomfortable.
- The impression gun needs an improvement to be able to use a whole DS-50 cartridge - it leaves about 1.5 cm in it.
- Applying the foam stop yourself is quite easy. I think it is much harder to put one to somebody else's ear canal, even with an otoscope and/or correct endoscope.
- Lacquer coat is best done by dipping a whole impression in it. Have to really attach it to something though so that it is easy to get out.
I've made some new pictures and also a movie, but it is missing the foam stop application step. I'll make a better one later, anyway there are plenty of those on the net, it's not anything special.
Grrr, I had to post this multiple times, got a white screen. The remaining pics are available here on Dropbox (https://www.dropbox.com/sc/zxnumssm5879nf0/p1HJ_hUlLg). Unfortunately I can't link to them directly, or they don't get the nice thumbnails and take the whole page. :)p10
Also a friend's "gypsum bust" project: pics on Dropbox (https://www.dropbox.com/sc/a6w3p1b7q0eked2/OOTLjdUHQH).
-
Great progress AS! So you're doing all the impressions to yourself? That feels like it must make it more difficult, but seems you're handling it well. :)p4
My wife is much more interested in the Gypsum Bust project!! That's right up her hobby alley!
-
Doing the impressions yourself is part easier, part harder. The easier part (if you have a steady hand) is placing the foam stop correctly - you will feel it expand and be very uncomfortable at the right depth.
The hard part is actually applying the impression material - the position, especially with the gun, is highly unnatural, as if you were touching a shotgun to your forehead from the side - and you also need to exert non-neglible amount of pressure on the release.
About the bust thingy - what the friend was doing here is the following:
- Take a Guy Fawkes' mask
- Build a polyclay (non-sulphur plasticine maybe?) sculpture of the same shape below it
- Put the mask on it and fill any missing parts, cut any excess as necessary
- Cool it down so that the clay hardens
- Apply silicone with thixotropic additive and some light petrol solvent - the reason for the solvent is that the silicone was very old. Acetone didn't work.
Later plan likely involves filling the resulting silicone mold with gypsum, we'll see.
I'm not entirely sure why he used silicone there for any reason, I'll ask again.
-
Next step. I've managed to remove the impression from the form, it was quite a bit harder than expected - it adhered very well.
At least it was possible. Now I'm making the positive with a 4mm silicone tube in it as a custom tip for RE-400. Should be similar to shallow fit I think, I can always try to cut a deeper hole for the IEM. (Try being the operative word, because I don't have the right small enough tool, so I'll have to use a knife.)
This time the negative was coated in Ease Release 205 (5% silicone separator liquid) by dropping a bit of it into the negative. That should make it easy to separate... or will not work at all.
Made the positive from the harder slow Mold Star 30 to just check the mechanical properties of this silicone. I will have to work it a bit as it will have some surface flaws. Probably both with a Dremel tool and some solvent.
Tubes are stopped with a bit of paper on both ends. I could use something more advanced, but this should serve and be easy to remove.
A possible mistake: applied demolding liquid while the tubes were in place, so they might not adhere well. We'll see.
Also tried to further the silicone foam experiment, but our microwave (already broken), broke the faux rotating plate in a hilarious way.
On a related note, we now have a decent rotary medium vacuum pump. Need a transformer, oil and a vacuum chamber to remove all kinds of air bubbles.
Notes:
- Do not use fast silicones without vacuum pump. There will be air bubbles and they will be annoying in a negative.
- Smooth impressions should be much easier to unseal. I've been testing with the lousy "clear" ones with holes filled manually.
- The soft Mold Star 15 Fast silicone is very resilient, doesn't change shape even when relatively large forces are applied.
- Next time try not to cover the ear mold over with the silicone when making the negative, as now the impression is shallower than I'd like. Not deep enough for a full size CIEM. For that, I need to mount it shallower and use a bit less silicone.
- Silicone tubes are stopped with
Pics included. The microwave one was more hilarious in real life, esp. while it was still shining bright The weird blue stuff (both in microwave and in the pic with the large cup) is the silicone foam mix, first version. I've cut a cylinder for foam tips with a rotary tool, which is not the best way - done properly it would have a smooth surface.
It is workable in hand while semi-thick, but I don't have vinyl gloves - will have to get a bunch of these. Normal latex gloves contain sulphur and will prevent silicone binding.
-
Ok, messup that turned out semi-ok, considering how poor the impression and negative were.
The tubes fell off (were pushed out by the IEM) and the hole happened to be too wide for RE-400 nozzle it was planned for.
The ear canal parts are actually completely missing, as the tube is too large diameter to allow any reasonable quantity of silicone to pass down.
Demolding silicone from silicone was about as hard as previously, maybe slightly easier. Mostly hard because of the irregular surface on the sides of the mold, which were incompletely covered with the unsealant. The ear part actually demolded very easily, meaning Ease Release is essential.
The slightly harder silicone (Shore A 30) is about the same hardness as the one used in SE-5.
No bubbles in or on the positive, which means this silicone is suitable for accurate molds, both negative and positive.
I didn't bother to round out these "broken"impressions, just cut off the excess with rough knife cuts. The cuts were a bit tricky, the silicone is highly elastic and there was lost of excess.
Short version of the result: Generally similar to long tips, except more comfortable (still not superb due to bad impression) and way better at soundstaging. The. Best.
Balance is reminiscent of very deep fitted Brainwavz B2, except not "sparkly", instead bit "hot", much better upwards extension, no bass boost.
And now for the good part - the IEM sounds very closely to equalized with these "tips" or rather mounts, once they fully seal. Better soundstaging in fact, reminiscent of the other CIEM without its weaknesses. Isolation is not great, on par with EtyPlugs, bit lower in mids and bass, higher in highs. The silicone is very acoustically transparent in this small amount.
Some 4k hot boost is apparent, perhaps could be tamed by the return to original filters as well as another high freuqency peak (14k?). Air is better than even the equalized. It is semi-shallow insertion. (-3mm? I'm not sure whether to measure from the nozzle or the target tip position.)
It is tricky to put these "broken" impressions in so that they fully seal, but they hold well once in, right ear much worse than left - does unseal at times; not entirely comfortable either, on the tragus - I filled that area in as there was a hole. (Remeber that was with that terrible clear material.)
Bass is highly "thumpy" but more of "pressure" kind than "ear shaking" or "bone conduction", which means the bass is likely balanced with exellent subbass, without typical 36Hz boost.
And pics. I've actually pushed them in bit deeper than shown in these pics. The in-ear one shows almost the correct depth.
EDIT: few more cuts fixed the comfort and improved seal. Cut based on the better impression (rather than my guess) improved things further. The main gain from the better seal is that the IEMs sound bit bassier still ("kickier" but not boosted) and faster? 4k/14k resonance was reduced notably - that was probably the leak resonance. The sound is way faster than with all other tips and now I can put them in reliably. Gains in soundstaging again. W/o crossfeed, they sound binaural-like, with crossfeed, like an excellent, slightly bright, set of speakers - monitor-like. (No equalization yet.)
Still, will make new ones based on the good impressions for comfort and better seal. I'll use 3mm silicone pipe to make the hole instead of trying to actually use it as the canal.
-
AstralStorm How is it going with the 3dprinter stuff?
-
Haven't tried it yet as I don't have the 3D scanner. Now trying to make the right silicone tips with proper air ducts - this is proving hard.
I have some pics of failed attempts...
I'm trying a two-part process, where I make a silicone shell first, then put the tubing, then fill up.
Trying to work in a full shell is fruitless - there's no way to drill the right shape duct.
By the way, the polyurethane works, but not as a mold for silicone - so eems to contain something sulfur-based, slows down curing a few times - but it does cure in the end.
Adding Slacker to Shore A 16 silicone produced a material similar to those gluey silicone balls. Very sticky if rough, very soft and not too resilient.
More later incl. pics. More experiments on Sunday again.
-
This is awesome to read about as always. Are you in touch with Gregorz or anyone else in the industry to get some tips and advice?
-
Nope, unfortunately Grzegorz is in Poznań, while that Lime Ears guy seems really busy and I don't want to pester him.
Also it's more fun to figure it out myself. The previous attempt used a wire to guide the tubing.
The two part process should work assuming the first layer is thick enough. I should be able to remove it, cut a small hole and put the tube precisely through it, in addition gluing it in. Cyanoacrylate (superglue) glues silicone reasonably well.
Alternatively, I should be able to make a polyurethane positive and just drill in it, or a polyurethane shell if I put a spacer into it. Of course PU is not soft, but it does hold silicone on the surface reasonably well, especially if roughened...
I wonder though how to make a right size and shape spacer. Perhaps I should just sculpt it out of polyclay or make an initial thin silicone impression.
Oh, and the pics of the last two week's experiments. Missing the "soft shell" experiment, but that won't fly, I've made it too thin. Just "painted" the surface with silicone. Cannot probably do it in a silicone cup and hope to remove the silicone for machining. Perhaps it cannot be removed reliably period.
Polyurethane form is kind of a bust - while it is easier to remove silicone from it, the silicone takes 4x as long to cure due to sulphur compounds. Lacquering might help, we'll see once I get there. Plus, the first one I've made had a bunch of pits on the surface, making a rough positive. The other one was great.
I need to buy more small cups - wasted too much material on these large ones. Also need to make a new impression, the Siliclone one has shrunk enough to not fit well anymore.
Brainwavz B2 impressions (dark blue, with only the wire) almost work well, of cours ear canal wire routing was a complete bust. I don't have the right drill bit to drill in silicone - normal ones just bounce off it - maybe if I made a small hole beforehand... something to try.
-
Looks like you're having fun.
Any pics of the GR07 driver yet? Just curious, as I haven't opened up mine yet. <3
-
Ehm, that had an accident while opening. :-[ I managed to pry the shell open, but extracting the driver is a whole different story - will have to crack apart or cut the front part of the shell instead of trying to push the driver out (broke the cage and damaged the driver) or lever it out (broke the driver by ripping out the membrane). Clearly not meant for easy servicing. The shell is made for a "click in" fit of the driver, once it's in, it's very solid.
Next time I'll break the front part in such a way to leave some of the driver exposed, I should be able to pull it out by hand.
Not much to gain by looking at a damaged driver, but if you really want to, I can make the pics tomorrow.
First though, I need to figure out a way to put air ducts in the positives and the ear canal. Either by properly placing the silicone tubing then gluing it in so that it holds, or by putting in a silicone wire or a metal wire in such a way to make a duct. Drilling it out from the positive or the impression is almost impossible, ear canal geometry is too irregular. I've tried that and damaged one of the impressions.
-
I'm interested in seeing the broken driver ~
Thanks, I'll open mine from the front then and try to be careful.
-
Have a pic, sorry it's not any better, but I did manage to "safely" remove one of the driver after mangling it. You will see what I mean about cracking the front part of the shell. That works. To do so, remove the back part using a flat screwdriver, remove the adjustable nozzle, then grab the front with small pliers and break it, so that the mounting ring breaks. Then you can remove the driver by hand, as the remaining green glue does not hold it strong enough and it's available for proper prying apart.
I've also managed to finally hurt myself by taking the impressions with a slightly too small stop in the right ear. Silicone flowed past it a bit, sealed way too well and I damaged something taking it out due to overly high negative pressure despite being quite careful and slow. I'm pretty sure I've mildly damaged my eardrum (or most likely the delicate blood vessel on it), but (hopefully) not badly. No hearing loss or pain apparent, I was actually semi-suprised by that earbleed.
This means a month's stop in taking ear impressions - fortunately the pair I took are ok so I can proceed with the tubing experiments. Lacquered them already.
I really have to get a refill on small mixing tips and get large ear dams.
The price of pirate science. facepalm
-
Nice pic, thanks, looks like transparent bio-cellulose from what I can vaugely see there.
The Sony E888 bio-cellulose earphone was known to break at loud volumes, the diaphragm would tear, mine did so I mended it with cotton.
I'm wondering how Vsonic made the GR07 diaphragm so much stronger, since I've actually pushed it to maximum volume on an iBasso amp with high gain.
-
Trivial. GR07's membrane is ever so slightly thicker and much lower tension. Sony likely has a very tense membrane, that's why they have way more high frequency modes and why they had to add foam/rubber ring mounts or it'd break on a cough. (also for dampening, which it doesn't have enough of either)
Of course I'm only inferring that from the published driver construction diagram.
GR07 has very few breakup modes up high - the 6.5k/14k peaks plus plasticky ringy reverb come both from the shell, not fully dampened half-wave resonance, relatively easy to fix.
Have a nicer pic with more light, not much better though.
-
That's a much better pic, cool!!
I asked Thousand Sound once when I was feeling adventurous if he'd use my GR07 in their TS842 or their newer TS853 and he said no, no and no, plus no.
http://englishbutler.jugem.jp/?eid=34
Anyway looking forward to your results.
-
Speaking of hybrid, here some work I have been doing in past few days.
https://twitter.com/MeiZu2/status/394855108061589504/photo/1
-
I'm not seeing any space for the BA in this hybrid. Are you planning a mostly empty shell for a dynamic driver, or some specific kind of dampening?
-
If you see closely you can see that TWFK sits in the nozzle. The TWFK is from q-jays.
The DD will be 13mm its really fast and matches the TWFK BA. You can see the DD will be fixed in round shell. Will post real pics on weekend. The shell is ready.
-
Are you planning a mostly empty shell for a dynamic driver, or some specific kind of dampening?
Do you think dampening like in headphones on backside will work? I was planning to use the empty space in shell just for crossover. I think ASG & 1plus2 uses some dampening.
-
Sure it does. I've tried such a mod for even stock headphones, can change the sound a lot, by removing horn effect of the shell and/or half-wave resonance.
With RE-400, made them mostly electrically flat - FR similar to Paradox. With GR07, small amount of cotton wool in the back drops plasticness of the sound and tames 6k peak.
-
https://twitter.com/MeiZu2/status/396250843042684929/photo/1/large
https://twitter.com/MeiZu2/status/396250072330948609/photo/1/large
https://twitter.com/MeiZu2/status/396250323376820224/photo/1/large
Some progress on IEM.
-
Decent. I was always looking for a way to not have the 12dB/octave treble drop, like the WBFK you used (most likely) has.
Nice balance lower down too.
Now I've found Surface from Motion software and will try to use 3D modelling as a solution to a few issues, such as creating a silicone shell (not full mould) and lock mounts for the silicone tubing or maybe printed ABS tubing.
-
https://twitter.com/MeiZu2/status/396685039770931200/photo/1
TWFK connected in reverse
-
That connection just uses the WBFK with a highpass filter + FK without a lowpass filter instead of FK with a lowpass filter + WBFK. Actually quite a decent setup, but WBFK + FK can still be overloaded by too much highpass, so cannot be made nearly linear at the highest end - it will distort audibly and the capacitance can make some amplifiers distort. I think in this configuration, it can be made linear via eq, but not in the default one.
In comparison, a few Sonion models can approach highest end linearity and most dynamic drivers can be highpassed with impunity for superior air - and air is the thing most IEMs lack. Of course not all dynamic drivers, only the lightly dampened ones, other kinds will not respond to the highpass. (GR07 needs a lot of it for linearity; RE series work extremely well as a tweeter once equalized.)
-
hmm, IE8 and RE-0 seems to extend further than the TWFK treble. What sonion driver are you referring too ?
-
Check the thread, near the first post. That one was from 2300 or 2600 series. It's half of the AcuPhase, just like WBFK is half of TWFK.
I still need to contact a Sonion rep or distributor.
By the way, today I have to make a headlike attachment to a speaker to simulate a HATS-like sound source. Loads of fun!
Design: half of a rubber ball of the right diameter, lots of cotton wool for fill, paper tube to keep the "mouth" open, a cutout for the mouth, bit of silicone on it to simulate lips, perhaps some bit of plastic to simulate teeth.
I can use PU foam instead of cotton wool if there's still too much reverb - and if it's necessary to shape some resonant cavities.
The source speaker is Behringer C50A, if anyone is interested. Probably the best single-driver monitor cheaply available. (barring custom made ones)
EDIT: due to low availability of rubber balls, I'll have to make a silicone cast instead. Annoying.
-
http://www.sonion.com/Products/Transducers/Receivers/~/media/Files/Products/Data%20Sheets/Transducers/Receivers/Receivers%202300/Receiver%202300/2389_v3n.ashx
Specs of 2300 doesnt seem to indicate so.
I have 2323 which shows similar on measurement.
-
I did tell you to read the first post, didn't I?
Sonion 2354 and Sonion 2359 are way different:
http://www.sonion.com/Products/Transducers/Receivers/~/media/Files/Products/Data%20Sheets/Transducers/Receivers/Receivers%202300/Receiver%202300/2354_v2n.ashx
http://www.sonion.com/Products/Transducers/Receivers/~/media/Files/Products/Data%20Sheets/Transducers/Receivers/Receivers%202300/Receiver%202300/2359_v1n.ashx
On an unrelated note, have a few pics of the talking head simulator attachment.
-
Ok, back to it. I've managed to get good 3D models out of the pictures of the impressions, here are some pointers if you want to do the same.
- You will need either VisualSfM application (which is only licenced for non-commercial usage) or learn to use Bundler and CVMS from OSM-Bundler package. (OSM being Open Street Map). Googling these is easy.
- 30+ pictures from all the angles are necessary for good reproduction.
- Good strong lighting is a must. Flash causes the process to fail.
- Cellphone cameras tend to provide worse results, such as not being able to focus properly on such a small object without sharp edges. Manual focus is recommended.
- Best distance is about 50 cm to 1m.
- My pictures were done with Canon EOS500D, which is in the Bundler database, but it is not important unless you want to keep absolute scale.
- Take pictures one impression at a time - for multiple impressions at once, the results were not acceptable.
I've also attempted to make a pair of "fillers" out of PU by filling PU impressions with a layer of silicone putty and then filling the remaining space with the PU. However, the experiment has failed right now due to silliness on my part, I'll retry next week.
On the other hand, I've ordered way better silicone supplies now, they should arrive late this month. This includes special PU foam mixes (stiff and soft), transparent silicone and PU, high performance condensing silicone, high temperature (300 °C) silicone for future attempts at zinc-based shell, high hardness (Shore-A60) silicone for structure.
Perhaps later I'll order some actual mechanical handheld tools which can work in silicone and PU precisely.
I forgot to mention I also got sulphurless polyclay and plasticine - the other try to make the fills and perhaps clay shells too - which might be an interesting experiment.
-
Got all the stuff and...
- Dragon Skin FX Pro is an excellent silicone for the final CIEM, super soft and very resilient. Looks like the stuff used by the CustomArt guy, milky transparent. Super precise. Combined with Thinner, becomes bendable irreversibly like ballistic gel.
- Rubber Glass II was a mistake - it's an SFX silicone designed to crack like glass. Extremely translucent but not very resistant. I have experimented with making it a bit more elastic, we'll see how that goes. If that works, it will be superb for the looks.
- Foam-It III polyurethane rigid foam produces nice large hole open cell foam, rigid and very resilient. Will be useful for damping.
- Another attempt at mounting the 3mm tubes directly in the mold has failed.
- Attempt to make a skin mold has semi-worked with some holes, I'll try again.
- Handheld tool can be used to hollow out a ready made impression and smooth the edges. It is hard though to drill a hole through the silicone through the ear canal part, but not impossible. I'll just need a different drill bit.
- Crystal Glass 50 is a very resilient, hard polyurethane transparent rubber. Will be another good choice for a shell or full mold. It is machinable and that easier than the silicones.
- Thivex and Thinner work as advertised.
- Royal Jel-E also works as advertised, decent silicone-silicone demolding power. Does not work for urethane.
- Super Seal lacquer sealant works ok, but for silicone-silicone, Royal Jel-E is better. It is essential for silicone in polyurethane.
I haven't tried Flex Foam It yet, I'll need the mold silicone for that. Haven't tried the silicone glues either or the plasticine. For the latter, it seems sculpting such a weird shape by hand is harder than it looks. I'll instead heat it up and use it as a mold, then reduce delicately.
Ordered Mold Max 60 (hard, high temperature, condensing so good for polyurethane), Rebound 25 (for skin/pouch molds, very precise) and Body Double Fast for making the head mold - just apply liberally over face and ears, demold in 4 minutes.
Couldn't do the 3D print, as the printer had some problem with filament feed. Will try later today.
-
Prepared RE-400 for CIEM makeover, that's how they look now.
That white thing is high density, pressed cotton wool, amount deemed optimal by Vas calculation. (That is one weird driver.)
It has been coated with a sealant lacquer and is quite rigid. The cyan thing is a bit of silicone coat, later "waxed" into the surface to make it even more waterproof.
The sound is sweeter, warmer, airier and much more linear. There is a small 1kHz dip present, the highest end lacks only 6 dB to linearity. 2k peak is gone. Subbass is linear and the bass becomes 3D.
Sound is more coherent and smoother, while slightly improving in precision, especially in lower midrange.
The filter and foam had to be removed, they turned the sound really really dark. Medium depth fit with the pictured tips.
-
Herd-fi post with instructions for dumb people: http://www.head-fi.org/t/632802/hifiman-iems-re-400-and-re-600/2130#post_10180957
-
New developments with new methods.
Now trying for a pouch mold instead of a full negative - should be easier to work with. This one is with Mold Max 60 condensing silicone, high temperature so should be good even for, say, zinc shell. Very stable silicone and friendly to urethanes if need be.
I'll try to make a 1 mm "skin" for the IEM from Rebound 25 brushable or Dragon Skin 15 FX Pro (both pretty fast) then additional hard fill from Mold Max. This will serve as a "skin" mould - in which it should be easy to install various equipment, and the inside "plug" will make it easier to create replicas.
I'll use PU foam as the rigid support for the pouch, but that should be really optional, as Shore A 60 silicone is quite rigid. Dragon Skin is milky transparent, so various color effects are possible. The surface is not smooth to touch though, but for that I have an additional thing - Smoother.
The other test involves silicone foam - I'll try to make custom foam earphone tips / plugs. It might be possible to create a layer like that on a CIEM to alleviate any kind of misfit. It's supposedly highly resilient and can be colored. That foam is Soma Foama 15. High end stuff. It will also be used as dampening (after cutting off the smooth layer - it's open-cell) and as anti-vibration mounting.
EDIT: It seems that a soft pouch mould is pretty much required for it if you want it to expand beyond. It's still slightly expanding and definitely not fully cured after 30 minutes. Looks nifty though. Less memory than Comply, but way softer. Not sure about tensile strength - it's supposedly relatively hard to tear once fully cured. Demoulding it from even a soft full negative (non-pouch) was very hard.
I've also managed to finally create good 3D meshes out of ear mould pictures via SIFT + Bundler + PVMS2 + MeshLab. (Actually, this trial run was on some other weak machine and I used reduced resolution pictures, so probably lost some points.) It's not yet final, but definitely is viable. I'll also have to try with zoom and/or in macro mode for more details.
Good lighting and focus are a must. I will need some additional object for proper scaling next time. I'll try 3D printing these meshes - of course a 3D printed surface is not really smooth, so it won't be usable as a whole shell - but the meshes are very useful in CAD for designing tube locks, placing air tubes, calculating volumes etc.
Next work will be on applying some freshly acquired Body Double to copy my outer ear and cheek shape. The goal of that subproject is to make a personal ear-and-cheek simulator.
-
Dunno man that picture with the red painted molds is for some reason... disturbing... DT-990 flashback... :-0
-
Dunno man that picture with the red painted molds is for some reason... disturbing... DT-990 flashback... :-0
Haha, that isn't paint, it is silicone. Mold Max 60 is ferrous red colored. I can say that these first pouch molds will have a hole here and there, as a bit got damaged by carelessness before it fully cured. I can of course fix that tiny issue - it's not in the critical place - or of course try Rebound 25 brushable for another pouch.
--
The above pic is alginate in gypsum support - sucky indeed. I have a way, way better material - fast thixotropic (read: brush-on) silicone for body doubling, I'm eager to try it out but not exactly in the form you described.
-
Darn, the silly forum logged me out while I was writing a post.
Long story short, I've made a clone of my outer ear and the pouch mould. Had to made new impressions, as Mold Max 60 is too hard/brittle for pouches and holds on to impression silicone way too well even with unsealing agent. Removing that would take eons if it's at all possible.
Body doubling is tricky - have to use huge amounts of vaseline (incoming nasty jokes) so that the hair are safe. First time I haven't applied it everywhere the silicone flowed... that was quite painful.
In the final and decent (but not perfect) attempt the silicone was applied by a friend - he made a few minor mistakes though.
Both Rebound 25 and Body Double are extremely good brushable thixotrophic silicones, but I could use a working vacuum pump to remove air bubbles. With the aid of Smoothie surface smoothening spray, I can fix any minor issues by hand pretty well, should they occur.
Pouch mould will be used to create a silicone shell (again out of either Body Double or Rebound), which will then be used for installation of the tubing, dampening and the driver.
I'll attempt RE-400 first - but I need to fix a broken trace there. Should that fail, TWFK from Brainwavz B2 is on the standby, with a slightly more aggressive dampener than the original one.
The requisite ear canal volumes until the second bend are: ~1 cm^3 for RE-400, ~0.33 cm^3 for TWFK. I'll compute the exact placement and tubing based on the 3D model made earlier.
This means a shallow insertion on RE-400, even slightly shallower than with long RE-272 biflanges. To achieve that, I might have to rotate the driver and bend the tubing into an S shape without kinks or create an acoustic chamber larger than the tubing I have. (Largest diameter is 5 mm inner.)
The ear doubles are for the ear and cheek simulator to be done later.