Home-Made IEMs
Jun 27, 2017 at 9:12 AM Post #6,616 of 15,910
For the greater good I decided to sacrifice a GV driver to determine once and for all the values of said components.

1. There are no resistors in this quad. Just capacitors.
2. I believe but not 100% the TWFK used is a 60173 which I will post a pic of, and I believe it already has one capacitor attached which is the same value as the one on the GV. Obviously the positive thermal wire would need re-routed to the config in my drawing.

TWFK-60173 available to purchase at digikey. Spec sheet is here.

IMG_3084.PNG

The HODVTEC wiring is crossed, which I have attempted and it does work.

The capacitors looking at the pic below are as follows.

Right capacitor reading was 5.13uf - there could be a tolerence so it is likely a 5.2uf or a 5.0uf.

Left capacitor reading was a 0.52uf - there could be a tolerence so it is likely a 0.47 uf as that is common.

IMG_3083.JPG
 
Jun 27, 2017 at 10:51 AM Post #6,618 of 15,910
Nice work.
One thing to check before you solder everything back is the DC resistance of the twfk and hodvtec.
Because the 60173 seems to have a very high impedance.
upload_2017-6-27_17-50-57.png

This is the GV
gfgf.JPG

This is the regular Hodvtec 31618
upload_2017-6-27_17-56-56.png
 
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Jun 27, 2017 at 1:12 PM Post #6,619 of 15,910
Nice work.
One thing to check before you solder everything back is the DC resistance of the twfk and hodvtec.
Because the 60173 seems to have a very high impedance.


This is the GV


This is the regular Hodvtec 31618


I will see if I can get the DC resistance later when I get home from work.

I purchased some white UV curable ink today. I'm interested in seeing how it mixes and cures.

IMG_3085.PNG
 
Jun 27, 2017 at 4:30 PM Post #6,620 of 15,910
Does anyone know of a good link where I could learn to wire in capacitors and resistors, etc? I understand some of it but I don't know how to wire them in series and then do I wire multiple speakers together in parallel? Lol. I'm totally lost. I would just like a nice simple build that went into detail about wiring them up. I look at some of these diagrams on here and feel encouraged but at the end of the day I'm still lost lol.
(Also, which capacitors and resistors do you guys use? It seems some are larger than others...not in value of resistance, but bigger in size. But then some guys use really small looking resistors,etc)
I know this is a ton to ask. So just any help at all would be appreciated!
Thanks
 
Jun 28, 2017 at 4:05 AM Post #6,621 of 15,910
Does anyone know of a good link where I could learn to wire in capacitors and resistors, etc? I understand some of it but I don't know how to wire them in series and then do I wire multiple speakers together in parallel? Lol. I'm totally lost. I would just like a nice simple build that went into detail about wiring them up. I look at some of these diagrams on here and feel encouraged but at the end of the day I'm still lost lol.
(Also, which capacitors and resistors do you guys use? It seems some are larger than others...not in value of resistance, but bigger in size. But then some guys use really small looking resistors,etc)
I know this is a ton to ask. So just any help at all would be appreciated!
Thanks
Regarding components sizes you are looking at SMD components "usual sizes used" are 1206 and 0805 but you can go bigger or smaller
smdsizes.png


Soldering the component is like you said mostly, drivers with their components are usually connected in parallel with each others. Here are an example of a Low and High driver with a cap to the high as an high pass filter and a resistor to the low driver.
Pay attention that some tantalum smd capacitors have a polarity sign (brown line) so it should be toward the input positive (although I am still not sure if it really matters).
upload_2017-6-28_11-5-14.png

Here you have the same thing but with a low pass filter to the low driver, so the capacitor is wired in parallel to the bass driver
upload_2017-6-28_11-17-29.png
 
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Jun 29, 2017 at 5:28 AM Post #6,625 of 15,910
That is weird how it's end of life already, I wonder if it infringed on someone's design and therefore they were forced to pull it. better order it while you can that's for sure. I wonder if anyone has been able to get the values of the cap and resistor yet. I've been making quads with the design I posted several pages back with great success. Everyone I've made them for are extremely pleased with them, on my last builds I've been using this setup and love it.




Here is a pic of a 2-driver set I made for a friend. White faceplates with custom graphic.

Shiloh,
1st, you may not know it, but thanks for all you do here! You're always helping guys out. I've learned so much from your post. Love those new ones, but all of yours are top shelf!!
I thought the same thing about those BA's. I bought the GV's for my 1st build. So far, I've got them to sound pretty well but have just now got the shell making process down. Haven't really put anything all together yet. Learned the hard and expensive way just playing around with some old DD's, now it's turned into a hobby. I'm working on trying to get the recommended R and C but am really just getting started on the details of the sound. I suppose I better order some if they are going away since you said they seem to be a good bundle. I just didn't want to fork out that kind of cash isf there was a problem I didn't know about. Couldn't find anything on the web.
Thanks again
 
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Jun 30, 2017 at 10:54 AM Post #6,628 of 15,910
From what you know, are the caps correct values for this setup?
No, the impedance used in calculations is DC resistance, instead of Z impedance. As we know standard BA drivers are inductive and thus non-linear in impedance.

[Edit] Plus the scheme is mixed up. You wouldn't connect woofer portion through 2nd order cross-over, but tweeter, so even the assumed DC resistance is incorrectly put in equations.
 
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