[kyMal]

following

 

[swtnate]

I have had these universals for going on 10 years now. They arent really anything special at all but Im sentimentally attached to them when I fly or travel. The cable is permanently attached AND its flat (not the traditional round). Any trust worthy universal builders have any ideas or suggestions I could use to repair? Soon it will pinch completely off and all hope will be lost.
HELP ME OBI WAN KENOBI! YOURE MY ONLY HOPE!

 

[Wgibson]

Sugru is good for that. Hot glue for immediate but temporary fix.

 

[mattmatt]

I have had these universals for going on 10 years now. They arent really anything special at all but Im sentimentally attached to them when I fly or travel. The cable is permanently attached AND its flat (not the traditional round). Any trust worthy universal builders have any ideas or suggestions I could use to repair? Soon it will pinch completely off and all hope will be lost.
HELP ME OBI WAN KENOBI! YOURE MY ONLY HOPE!

Either recable them or print a coupler that attaches a 2 pin or mmcx socket.

 

[swtnate]

Sugru is good for that. Hot glue for immediate but temporary fix.

Sugru? Do you mean super glu?

 

[jcaro]

Sugru? Do you mean super glu?

Sugru is a brand name for moldable glue: https://sugru.com/how-to-use-sugru

 

[IndyAudio14]

Big Update guys!

MASM 7 Reborn (easier than ever), made possible by the help of @dhruvmeena96

Disclaimer: might or will sound different from the regular build, since we're using different tube material & slightly alter the zobel using easier to find component.



No need to to do extra work, almost everthing was 3d printed(tube, BA mount, mmcx mounting, pcb Mount), integrated into the shell

STL links:
https://drive.google.com/open?id=1yGw0EpCd44TYAePnwlNiKSalUp56inNU
https://drive.google.com/open?id=1ymxqtwum8yw-avV6yLavAoVgbl9jGTiu

BRD for zobel:
https://drive.google.com/open?id=1fF1GVznc29R9Ic7dj6x1k_NHe8hPS2Gs

Assembly Guide:
1. Print the PCB (it can fit 1,6mm, but 1mm dual layer is recomended, or anything thinner is even better)
2. Print the Shell (SLA, DLP will do the job, but need some post processing)
2.A. Sand the shell to remove leftover from printing support, you can also coat the inside with clear paint/nail polish in this step to get crystal clear finish inside the shell.
3. Solder everything in place:


A. 15 Ohm SMD 1206
B. 10 Ohm SMD 1206
C. 22 Micro Farrad Caps 0805
D. 82 Ohm 1206
E. 4,7 Micro Farrad Caps 0603 (this one is a bit different from original recipe, easier to find)

4. Solder all the wire, connector & BA (RAB-32033 & Bellsing 10013), the shell will fit Slotted MMCX. Please note the wire orientation & wire length while soldering everything, please consider the way we're gonna put it into the shell.
5. cut some tubes in a very small length, just to fit into the BA's spout to function as an adapter & seal.
USE EPOXY GLUE/NAIL POLISH TO GLUE THE TUBES, i've been constantly prying open my masm7 everyday for 3 days, tingkering around on each component, only to find the issue was the tube seal leakage


6. use 2,2mm drill to enlarge the BZ6 Hole from the nozzle, (only if needed), make sure you stop after drilling 10mm.
7. Put the damper in BZ6 nozzle hole, white damper at 10mm(it'll stop at 10mm, since i incorporated a stopper inside the tube), brown damper at the nozzle.
8. Assemble everything in place.You may use some glue to hold the BA in place, or cut some tube as spacer between the BA and inner wall(non-permanent build, might alter the sound)
9. The mmcx should have some space around it, fill it with some epoxy glue.
10. close & glue the faceplate.
11. Do the finishing touch, either clear nail polish, spray paint, or anything as you see fit

The shell is thick for sure. will do update for a thinner shell.

Hope this will help everyone.

Changelog from the original MASM7 recipe:
- slightly different caps for RAB zobel
- RAB's tube is stretched to 30mm for phase correction, calculated by @dhruvmeena96

 

[IndyAudio14]

Hello,I was wondering if anybody out there new of service that printed shells SLA,DLP for reasonable price.

 

[JASON99]

@JASON99 instead of a damper, you can try smaller tube diameter. Cut a small length to insert into existing tube. You can make a resonator this way with 2 pieces, if you get bored

hi sir,
I changed the mid , high tube diameter today.
Fr graph was not changed dramatically, but the sound was changed. Thanks for your opinion.
Anyway , i used bass unit 38d1x. It had a good subbass. But I felt the midbass was lacking…
In this situation, which one is the best sulotuon? adding midbass ba (31618) or increasing bass tube diameter

 

[StephenJames]

Has anyone here come across or used the Alsilience store on Aliexpress? https://www.aliexpress.com/store/1103295014?spm=a2g0o.detail.0.0.2fbdXgmvXgmvXx
I've used Amplisound and of course Soundlink with no worries, but I just came across this one now. Has good feedback, so I'm guessing it's all legit.

They sell in single units, which is great, as I lost a single 2389 in the process of my wife kicking me and all my tools off the kitchen table, so we could have a family xmas without earpieces, drivers and a soldering iron in the way. How, rude I know.

It's cheap enough, so I'm just gonna buy it anyway and find out for myself, but I noticed that they had 38D1XJ007Mi/8a drivers for a lot cheaper than everywhere else, and I've been tempted to try this driver for a while now.

 

[Wgibson]

hi sir,
I changed the mid , high tube diameter today.
Fr graph was not changed dramatically, but the sound was changed. Thanks for your opinion.
Anyway , i used bass unit 38d1x. It had a good subbass. But I felt the midbass was lacking…
In this situation, which one is the best sulotuon? adding midbass ba (31618) or increasing bass tube diameter

I don't think the bass tube will change the response too much, the 38d1xj filter is at the spout. You can tape the vents and measure/listen, could help midbass clarity but it will lose around 3-4db.

 

[tonybuild]

Hi guys, i have question about zobel application for woofer ! So far i learned about Lpad, but i dont know what does zober do to a driver (woofer)? Does it makes it quieter? And what cap value i need to apply ?

 

[swtnate]

Hi guys, i have question about zobel application for woofer ! So far i learned about Lpad, but i dont know what does zober do to a driver (woofer)? Does it makes it quieter? And what cap value i need to apply ?

When implemented correctly, the zobel network will level the impedance response and provide a much more stable driver response. In turn, making it tamable. Using an L-pad followed by a zobel, works really well on the hvodtec. In some cases, a zobel, tubing and a damper will get it done.

 

[Wgibson]

Fixed some issues in the nozzle on these 4BA, 3 tubes, with switches and trimpot. Sonion 20x53 (big like a CI, I added a vent, flat to 10hz), Sonion 23x62, Knowles 33803 (TWFK assy with built in x-over). Good extension, good soundstage. This was the switch position with best phase.

With FIIO BTR7 4.4mm balanced.

 

[alvinlok]

Could anyone please provide me the crossover of UM50Pro? I would like to make one for my friend. The configuration shall be 22955+30017*2, but I can't solve the dip of the 30017's mids at 3-4kHz. Thanks!