[cswann1]

I just got my new Neutrik plug today, which was the last thing I needed to complete my recable of my K701's.

The cable was already connected to the drivers and secured. I had braided the wire and left it all ready for the 1/4" TRS plug. So when it got here I went to work.

I was very careful with the soldering and made sure there was separation between each wire. Everything looked good. I plugged them into my amp, spun a CD and........nothing.

I checked another source. Same thing. Tried another pair of headphones. No problems. There's definitely a problem with the AKG's.

So I removed the covers of the K701's and used a circuit tester to see if the current was getting to the headphones and that there was not a problem with the wiring. Everything checks out.

I did have some trouble with soldering the wires to the pins on the drivers. I guess it's possible that I got them too hot and damaged those ultra-thin wires that go to the driver coils.

Before I start trying to find replacement drivers, does anyone have any other troubleshooting tips?

Thanks in advance.

 

[pdupiano]

measure the resistance from ground to right and left channels. They should match the resistance from the spec sheet for the k701's. If the impedance is more than 1k, you have a problem.

 

[Punnisher]

If there is no response when you measure the impedance, you probably cooked the drivers completely.

 

[cswann1]

Thanks guys.

I don't have a multimeter, so I'm going to dissect these and see if I can see any damage. I don't see how I can make things worse.

I'll probably pick up a multimeter anyway, so I can perform troubleshooting in the future.

 

[pdupiano]

Um.. you won't be able to really see it. Unless you have a loupe in which case Id suggest you just go down to your local ratshack and buy a decent meter for now and future use

 

[Uncle Erik]

Get a $10 DMM at Radio Shack - they work well enough.

Did you heatsink the drivers when you soldered the connections? I suspect that you overheated the coils and melted the enamel insulation. If that happens, the voice coils short out and stop working.

In the future, pick up a couple of copper alligator clips. You can find them for a few dollars, you don't need anything expensive. Put those on the wire going to the voice coils - the clips will absorb the heat instead of the voicecoils.

 

[cswann1]

You're right. I can't see any damage to those little wires. The plastic that holds the pins looks good too.

I'll pick up a mmtr today an see what I can find out.

 

[dsavitsk]

I'd check the rest of the cable while you are at it -- it is just as likely the problem is on the other end.

 

[NiceCans]

omg that sux . . . I know how upset I'd be so I hope it turns out to be something simple and easy to repair. Good luck.

 

[Bonthouse]

There is nothing as upsetting as something like that.. I fried my Xbox 1 the first time I tried to solder so I know how you must feel..
What kind of soldering iron did you use? Because if it was a low watt soldering iron, you might be safe (I really hope so for you).
Lets hope it's just a fixable short somewhere!

 

[cswann1]

Well it's pretty clear now that the drivers are both gone.

I detached the new cable and plugged it into my receiver and then touched the wires to corresponding points on the plug of another pair of headphones. The signal comes through loud and clear.


I emailed AKG USA service about replacing the drivers. I hope they're not too expensive.

 

[-=Germania=-]

You may not need to.

See if you can find the tiny wire and pull a little bit through. It is enamel convered, so you will need to heat it up quite a bit in a solder pot or on the tip of your iron with solder there.

You can also try to do a driver repair which would require steady hands. Done three driver repairs and every one of them it feels like a heart attack. If you can gently lift the driver, you might be able to get access to the voice coil and undo one of the loops to get the little wire that you need. Just be very careful and use helping hands.

Good Luck man!

 

[leeperry]

happened to me once...I've got a crappy quality soldering iron and I had the fantastic idea of cleaning all the previous solder, and the damn uber thin wire got off

with a great deal of patience, I managed to solder it back...and that was 60/40 solder(very slow to harden)

but if they look perfect, indeed...open the damn thing, you got nothing to lose.

I've seen a video of soldering on drivers, you never wanna keep the iron for more than 1 second...keep going back and further, but never too long at once. and use cardas solder, it's great! very low fusion point and hardens in a second(couple of bucks on ebay)

sorry to hear your sad story

 

[cswann1]

Lesson learned here. Soldering a cable to a driver needs to be done QUICKLY.

And thanks Uncle for the heat-sink tip.

This would be a black day except that I received a couple of new tubes today as well as my new HD580's, which are some kick-ass headphones. I'm really enjoying them. The best thing about them is that if I decide to upgrade the cable on them.....no soldering

 

[r_aquarii]

i had the exact same problem you were facing when i recable my 1st akg headphone.
luckily i could i get a replacement driver at a low cost in singapore.

good luck to you