New Posts  All Forums:Forum Nav:

Recable DT770s - Page 2

post #16 of 40
Thread Starter 

I might be able to fix it.

 

I can see the wire sitting there and it doesn't appear broken (aside from broken off of the spade).

 

I'll take a crack at it when I have the time.  The wire is pretty short, so it's not going to be easy by any stretch.

post #17 of 40
Some good magnification and I had to connect mine to the middle post, don't try to tin it, it will just melt away. Give it a half wrap on the middle post and apply some solder. Check with a meter and fingers crossed. biggrin.gif

Sent from my HTC Desire HD A9191 using Tapatalk 2
post #18 of 40
Thread Starter 

Thanks for the tip.  I'll post my results when I get the chance to work on them.

post #19 of 40
Thread Starter 

Well, things seem to be going ok.

 

I've been sick, so when I got done with work I didn't feel much like leaving my desk.  I decided it would be a good time to work on the headphones.

 

I have no idea if the voice coil wire is on well enough (and I'm not sure how to measure the impedance to see if it measures out).  I decided, after a test fit, that I would test out the speaker prior to soldering any connections to it, just in case it was shot and I had to remove the wires again.

 

It sounded a little scratchy, but that could be due to my hands shaking.  There were a couple of moments of clarity in the sound coming out of the speaker.

 

Hopefully I can figure out if it's connected properly and if there's anything I can do to improve things prior to trying to assemble them again.  The fact that I heard any sound at all is encouraging.

post #20 of 40

If you heard some sort of sound I'd say you probably have the wire connected. The voice coil wire is lacquer coated so it will not make contact just by touching. I gave mine a quick half turn around the tang with a meter probe, then I heated up the tang with the tip of the iron and pooled the solder onto it. When It cooled I measured with a meter and got a very close reading to the other driver's value.

 

Just touching the audio wires to the tabs probably gave you that scrachy sound I'd figure.

Fingers crossed. biggrin.gif

post #21 of 40
Thread Starter 
Quote:
Originally Posted by TrollDragon View Post

If you heard some sort of sound I'd say you probably have the wire connected. The voice coil wire is lacquer coated so it will not make contact just by touching. I gave mine a quick half turn around the tang with a meter probe, then I heated up the tang with the tip of the iron and pooled the solder onto it. When It cooled I measured with a meter and got a very close reading to the other driver's value.

 

Just touching the audio wires to the tabs probably gave you that scrachy sound I'd figure.

Fingers crossed. biggrin.gif

Fingers crossed indeed.

 

I'm not sure how well it's wrapped, but I did something similar with the solder.  Harder to heat it up with the soldering iron due to the clearance, but I pooled some solder I have in there (though not the silver solder I've been using for everything else since it seems to take more heat to melt).

 

What setting do I need to put my multimeter at to measure the impedance?  I'd love to know if it's working right, or if I need to contact MrEleventy to see if he still has that spare driver.

 

I also had to do a bit more filing to get the mini-xlr to fit down far enough.  I hope I didn't do too much.  I filled the gap in the top (that I can see light through, but it must be leaking around the washer in front) with some hot glue and I have some blue tack that I'll put there too to hopefully dampen the opening and restrict any sound coming out.

 

Would be bad if I've gone to this much work only to ruin the cup itself...

 

Edited to say:

 

I think I may have figured it out.  Tested it using the same setting to test continuity (I think, I have very little idea of what I'm doing when it comes to DMM usage) and it settled on a reading of 83, which I assume means it's reading at 83 Ohms?  That sounds right to me.


Edited by liquidzoo - 6/14/13 at 12:25pm
post #22 of 40
Set your meter to ohms, 200 for 80's or 2K scale for 250/600's or even autorange if you have one. Measure the good driver first across the two voice coil tabs. Then measure fixed one and they should be within an ohm or two of each other.

Sent from my HTC Desire HD A9191 using Tapatalk 2
post #23 of 40
Just read the edit and yeah 83 sounds good!

Nice job!
Post some pics when your done.

Sent from my HTC Desire HD A9191 using Tapatalk 2
post #24 of 40
Thread Starter 

I will do so.  Need to take some more pics of the rest of the process now that I've got that driver working.

 

I have some of taking everything apart, and I'll keep taking some with each step from here on.

 

Question for you:

 

I know that your 880s are dual-xlr rather than single, but how much wire did you use from the xlr to the driver on each side?  I want to use enough that I can manipulate the driver into place easily enough, but not so much that I'm having to force a bunch of extra wire into the cup.

post #25 of 40
I used that fine Lutz type stuff from a headphone wire, the kind with no jacket and is just twisted with some fibre / thread type stuff. I don't have the proper name for it. I used about 3 inches for each as the stuff is very flexible and gives a lot of room to work. Another thing I just remembered I did was I trimmed the top most post off the xlr socket (closest to the flat part of the threads) a little with side cutters as I felt it was a little too close to the tabs, but keep enough to solder too. I also put shrink tube on the xlr posts just incase, but check your clearances, lower the driver and peek in. biggrin.gif

Sent from my HTC Desire HD A9191 using Tapatalk 2
Edited by TrollDragon - 6/14/13 at 1:03pm
post #26 of 40
Thread Starter 

That helps a lot, thanks.

 

I've been using some Mogami wire that's worked on for me, but I'm just afraid of it being too stiff for the job at hand.

post #27 of 40
If the wire is stiff then do be careful, I've never user mogami so I can't comment on it. The first wire I used was a little stiff and I believe that is why the tab pulled out.

Sent from my HTC Desire HD A9191 using Tapatalk 2
post #28 of 40
Thread Starter 

I think the first tab pulled out through a combination of wire too stiff, wire too short, and the fact that the xlr was about 1mm too high in the cup.  I've solved the last 2, I think; though I still may make a change in wire if I feel I can realistically solder new wires to the xlr that is already "welded" in place.

 

Just being overly cautious.  Definitely don't want to wreck these a second time.

post #29 of 40
I soldered my wires up after the xlr's epoxy hardened. Wires on the xlr's first, shrink tube on the posts, then solder to the driver. And mine are wired 2 wires + and 2 wires - on each side since all for pins are used on each side in a standard LCD 2 pinout.

Over cautious is never a bad thing.

Sent from my HTC Desire HD A9191 using Tapatalk 2
post #30 of 40
Thread Starter 

Agreed.

 

I should have some time to go through my wire tomorrow to see if I have something better than the (22 AWG I think) Mogami to use.  I have some 26 AWG somewhere that might be a better choice.

 

Mostly I had decided to use it to keep the same gauge of wire throughout, though I'm not entirely sure how important that is.  Seemed like a good idea to me at the time.

New Posts  All Forums:Forum Nav:
  Return Home