[eunice]

I only get around 8 pairs out of 100g, since I cover the face plate in resin too. Also I might have bigger ears than others

A 100g bottle will get you started. It’s enough to build some experience and order more if needed. After all it’s quite a few days of building. After making ~15 pairs it still takes me approx 5h to make one pair from start to finish.

 

[imsurokim]

I believe you can make 10-12 pairs with 100g if I'm not mistaken.

Dreve Fotoplast I/O and Egger LP/H are the "same" product (resin) from different brands. So you will need to choose one of them, and then you will need a lacquer to do the finishing coat. Both Dreve and Egger have lacquers too.

Here's some videos where you can learn about the process:

I already watched all video several times but nothing was telling me what materials I should get. They also get BA from McEar or Ali, but I am utilizing my broken old w3 iem. Do I still need sound dampner to go along with drivers from w3?

I only get around 8 pairs out of 100g, since I cover the face plate in resin too. Also I might have bigger ears than others

A 100g bottle will get you started. It’s enough to build some experience and order more if needed. After all it’s quite a few days of building. After making ~15 pairs it still takes me approx 5h to make one pair from start to finish.

Thanks for the reply. I am ordering Dreve resin and polisher.

 

[eunice]

Do I still need sound dampner to go along with drivers from w3?

Well depends on the definition of ‚need‘.

The driver is only a small part of the sound. In an IEM the sound stays inside a sealed volume of air, basically a resonance chamber. The shape of that chamber greatly influences the sound, do not expect your iem to sound anything like the w3.

The pros are capable of shaping the resonance chamber to achieve the right frequency response, in addition to adjusting the crossover. And even they sometimes use dampers.

For us DIYers, dampers are an easy way to tune the sound, even after you have built the iem. Just buy a damper tool and a few knowles dampers and you can experiment.

It’s not a must, but it helps to smoothe the peaks you might get from resonances.

 

[eunice]

Let me try to write a bill of materials:

Negative forms (=investments)

- your ear impressions

- a sharp knife to cut the impressions

- a dremel with a soft grinding wheel to smoothe the edges of the impressions after cutting and remove excess material

- wax + some way to melt it (a jar in a pot of water will do, wax melts at around 55C )

- a thicker piece wire to hold the impressions while dipping into wax

- agar-agar + some way to melt it (melts at around 90C but needs to cool down to below the wax melting point, again jar in a pot of water will do )

- cups with removable bottom. You glue the impressions to the bottom of the cup with a drip of wax, fill up with agar, wait until agar has solidified, then remove the bottom of the cups and take out the impressions. You can also use plastic cups and cut them open.

- something to take out the impression. Sharp tweezers will do, but a dental tool much better. With tweezers you sometimes damage the agar.

- tweezers. Good tweezers are important.

Shell making:

- uv curing chamber 380nm wavelength, a cheap UV nail light will do.

- some rotating platform inside the UV chamber

- approx 12g of fotoplast per pair of CIEM

- glycerin to cure the inside of the shell

- isopropyl alcohol for cleaning the tacky layer from the fotoplast after curing

- a UV flashlight (scorpion light) for curing by hand (eg curing the face plate)

- something nice looking for the face plate, I use wood veneer, but nail polish also works

- 1200 grit wet sand paper for sanding the rim of the shells

- Diamond bore for the dremel to cut the holes for the tubes and the socket into the shell

- some dremel grinding tools for adjusting the fit and polishing the shell

- lacquer and or polishing wax for finishing the shell

- a glue that stays clear and does not produce fumes. I use gorilla glue and sometimes dreve Fotofix UV curing glue


Inside of the IEM

- your drivers
- connector socket (eg MMCX or two pin)
- wire (I use litz wire, but it’s not cheap)
- tubing. I use very short 1mm inner diameter, 2mm outer diameter tubing to attach to the driver, then 2mm ID and 3mm OD to the nozzle of the IEM (I use gorilla glue to glue the tubing)

- temperature controlled soldering station

- blue tack is very handy for soldering

That’s from the top of my head, typed on my phone. I still hope it helps.

 

[dhruvmeena96]

Thanks @Rabid86 for implementation of zobel.

 

[imsurokim]

Well depends on the definition of ‚need‘.

The driver is only a small part of the sound. In an IEM the sound stays inside a sealed volume of air, basically a resonance chamber. The shape of that chamber greatly influences the sound, do not expect your iem to sound anything like the w3.

The pros are capable of shaping the resonance chamber to achieve the right frequency response, in addition to adjusting the crossover. And even they sometimes use dampers.

For us DIYers, dampers are an easy way to tune the sound, even after you have built the iem. Just buy a damper tool and a few knowles dampers and you can experiment.

It’s not a must, but it helps to smoothe the peaks you might get from resonances.

Gotcha. I am reading 115 pages long pdf created by this thread. It seems like it is just for acoustic tuning of the sound. Sound depends on how long the tubes are, where you put damper, which damper is used and so on. I love the sound of my w3, but always wanted little more bass out of them. I think I should try with white on TWFK and red on CIs first and see how it works.

 

[Choy Wei De]

Well

Go for GQ-30783 and RAB-32257


GQ-30783 => 2.0mm x 19.5mm tubing with a Knowles Green filter (1500ohm) at center of tube + Knowles grey filter (330ohm) after green filter
RAB-32257 => 2.0mm x 15.5mm tubing with Knowles grey filter (330ohm) at center of tube

no crossover required

some soldering required

@Furco design, sounds amazing

I really like how my RAB sound. I use 12mm of ID 1.0mm connect to the driver, then connect with 12mm of ID 2.0mm, white filter where the 2 tubes meet. With the filter cloth removed.
What should I expect if I include this GQ configuration inside?

 

[dhruvmeena96]

I really like how my RAB sound. I use 12mm of ID 1.0mm connect to the driver, then connect with 12mm of ID 2.0mm, white filter where the 2 tubes meet. With the filter cloth removed.
What should I expect if I include this GQ configuration inside?

Immersive stage, better bass compared to stock GQ because of RAB, better extension due to WBFK in GQ

And GQ has ED

GQ+RAB compared to RAB

Better resonant peak(damped and wider)
Better treble air(compared to RAB)
Better Bass compared to GQ(RAB bass)
Way better mids compared to RAB

 

[dhruvmeena96]

@ForceMajeure @eunice @Ivan TT @IvanNOON @zern_c

Here comes the 4 driver RAB final design

Fitear f111 horn unit can be used if you are able to source that out

Driver rising impedance fixed with zobel
4 driver in 25% load per driver and in series parallel shift and damp the resonant peak plus shift in lower frequency.

The Series acoustic expansion resonator with 5mm length dampens every peak, turning it into flat.(formula of resonator is hard, so I will post how to calculate once I have derived simple formula)
The 5mm length was tuned to act as a bigger opening to damp the ear side impedance of 3kHz, it helps in phase perfecting.


The resonator also act as a pressure buffer, so reduced air force in the eardrum, relieving pressure and also increase staging

Last is fitear horn(mentioned in rinchoi blog) this helps to regain the treble .

Add a 1mm length 4mm tube(tiny disc) at the end of horn so that fiting issues in ear is solved.

Enjoy

113dB on 22ohm
No hissing, series driver wit vent stacked outside, it cancel EMF.

Series drivers are hard to hiss

 

[dhruvmeena96]

You can remove horn and add 2mm lenght more and cross a tweeter with different tube(tweeter is still optional).

Even with 2mm tube, it will sound darn good.
Just make the resonator 4mm

But add a proper crossover
Low passing (prerty high, the point where the RAB unit starts to roll)the RAB and adding a WBFK/SWFK according to taste


Now I am going to work with perfect point crossover. Midrange as bandpass rather than high freq low pass.

(I have to learn crossovers from scratch once again, it is a tough topic)

Resonator simple formula and different resonator and effect will be posted once I get a proper formula from my simulations.

Series resonator, Helmholtz resonator, kliene and some other funny resonators.

 

[Choy Wei De]

Immersive stage, better bass compared to stock GQ because of RAB, better extension due to WBFK in GQ

And GQ has ED

GQ+RAB compared to RAB

Better resonant peak(damped and wider)
Better treble air(compared to RAB)
Better Bass compared to GQ(RAB bass)
Way better mids compared to RAB

I would prefer to have more bass, should I swap with a RAF or use a higher value on the dampers? And what is horn and reverse horn? I think I know what it is, but need someone to clarify.

 

[dhruvmeena96]

I would prefer to have more bass, should I swap with a RAF or use a higher value on the dampers? And what is horn and reverse horn? I think I know what it is, but need someone to clarify.

Well, I didn't mention on RAB and GQ build. But if you interested, then

A reverse horn is a muffler
Horn is a horn

A series helmholtz resonator(bigger cavity loading in small tube) is a type of reverse horn which is used to take down peaks in treble region

Often called as mouth of horn.

Before loading something in horn, if the response is peaky, or uncontrollable, the mouth is used to tame down the peaks so the horn gives a linear raise in frequency.

Loudspeaker concept

And I was applying tube physics and loudspeaker physics on BA(BA is technically a Armature in compression driver format, except of TIA drivers)

Note : Balanced Armature driver are all tweeter in open air, except for HODVTEC(that thing is midranger)

 

[dhruvmeena96]

single driver revelation

TEC = 10.2mH
RAB= 7.8mH

all driver having response in between these driver have inductance between these driver

HODVTEC is parallel dual, so it is low value

CI can be higher, but no driver will exceed 15mH and no driver will drop bellow 3mH

i think ED lies within 7mH to 11mH

what we need is real time impedance calculator and variable capacitor

Rz = Re(500Hz) x 1.25

so we know what resistance value is needed

and once we get to know the value of Cz

we can easily find the Inductance value of coil

Cz = Le/(Rz^2)


well even MATLAB can do it, but i would have to have proper impedance value per Frequency

@ForceMajeure @IvanNOON

 

[kmmm]

Sorry for interupting. My first CIEMs. With GV drivers. Question about dampers and tube length. Could anyone confirm this:

1500A damper (for tweeter) tube 14mm
3300A damper (for woofer) tube 20mm

(Dampers inserted halfway.)

 

[dhruvmeena96]

Sorry for interupting. My first CIEMs. With GV drivers. Question about dampers and tube length. Could anyone confirm this:

1500A damper (for tweeter) tube 14mm
3300A damper (for woofer) tube 20mm

(Dampers inserted halfway.)

https://www.instructables.com/id/Make-Custom-in-Ear-Monitors-DIY-CIEM/

same spec as yours, inspired from here
the most universal tuning you can get