Hi,You were talking about the speakers / measuring different on each side ,if they aren't matched at the factory (which some are) they can read different .I have had one speaker read 3 ohms & another read 2.6 or 3.2 Etc .

 

I'm talking about the headphones, yeah, which basically are speakers plus a bunch of other things. And yeah, the left speaker at the beginning, before stop working completely, was 20.8 ohm, while the right speaker was 18.6 ohm.

 

i use a homemade helping hands to hold all the wires apart. where they can't move around on me. then i have a magnifying glass i set up to view the wires. then i take each wire and use a razor blade to nick to red,blue green,yellow etc. insulated wires. then after the cut with tweezers pull the casing off the wire exposing the copper ones inside. now comes the hard part. i wipe the tweezers off with and alcohol wipe or on a paper towel. if those wires are touched with a human hand the oil off your skin will stop this from taking a bond. use tweezers to twist the wire end . then i use a resistor to apply the flux on the bare wire . this is tiny work so tiny tools make this i call "brain surgery" so much easier.
then i take a break as i turn on my soldering iron. i walk out the door to get some fresh air the turn right around and go back in. i wipe my hot iron off on a clean damp white rag and add a mm of solder to it. then i wipe that off and attempt to remember exactly the place i put the solder on the iron and wiped off and touch it to the flux coated wire. just a touch! all the time observing through the magnifying glass. as small as those wire is it should be tinned. i turn my iron off and leave again because this wreaks havoc on my nerves. then i return and check if it is tinned all the way around the exposed part i am working on. if somethings wrong i start all over again. when correct i go to the next wire

 

Wow, nice tips!

Never thought about oil of my fingers, that's right. You take a break, hahaha, that killed me. Nevertheless, I found one problem. I tried to avoid using the lighter (cause when I was doing it for the first time like a few months ago, I burnt the bare copper wire and didn't ended with a good result). So, I used a razor to scrape the isolating coating, but I ended up ripping off (breaking) the copper wire. The little wires are so tiny they easily get cut if you scrape them. That's why I got back to use a lighter again.

 

i can do the lighter trick for wire up to a size 18 but those on your headphones and some other fine wires the flame (1200 deg) takes the tensile strength out of them. brittle leftovers. i'm serious these little f ing wires drive me nuts. that's my claim about "brain surgery" ! i've soldered for over 50 years and i used to pull the wire out of my headphones or guitar cable all the time and i would solder them back on. learned how to build speakers also as i blew them out in my old tube amps. tube amp repair ,now that's another ball of wax1

 

A lot of 'hacks' work, but the idea is to have an easy fix that is dependable. 'Hacks' are not dependable. The braid is what you are describing as it's 'woven' together with the wire itself (which is usually woven around another non (but flexible) conductor). If you have it soldered the way you are doing it and are happy, then go for it.

I've done this for many years and I leave out the flame. Just heat the wires with solder and they will tin. Then it's easy to attach with minimal heat so as not to damage the plug or other components (such as the wire...)

Bottom line is get all parts ready to go together, including pre-tin of the 'difficult' wires. So minimum heat and mechanical stress is applied when final assembly is occurring.

If you do it enough times with a blow torch you'll probably get one that works. But it's not the suggested way, which is what you are asking?

 

I'm getting better and better! It's amazing to be able to fix this kind of things!

 

OK, once again I face a problem I don't understand, at all... I'm interested in discovering what's the problem with these headphones, so don't ask me to buy another pair of headphones. It's all about knowledge and understanding what could be happening.

So... I wanted to repair a pair of headphones that look like this:

Left headphone didn't work. So I bought a good quality jack 3.5mm plug, soldered correctly the cables and that's it. When I test with a multimeter the resistance between each pole, I get this:
Ground to left/right channel: 18 ohm aprox
Left to right channel: 35 ohm aprox

Those values are stable, the jack plug is correctly soldered, the measurements prove they should work just fine. Nevertheless, the right headphone is like 80% louder than the left one.

Since the jack plug is a good quality one (I've recently had problems with chinese jack plugs not being standard size, but it's not the case), the measurements indicate that all is connected and working fine... why on hell the headphones are still not working correctly at all?

If the resistance is the same in each headphone, how is it possible that they work differently?

I've tested them in 2 smartphones and 2 PC's. Same results every time. If the left headphone was broken inside the headphone itself, the resistance should be much higher, but it's not.

 

When you are measuring the resistances which of the three connections on the plug are you taking as ground?
It should be the sleeve as shown below:

 

First of all, that picture of yours is wrong, the right channel (ring), where the red cable is soldered, it's actually the left channel pin. The tip, ring and sleeve colors and indications are correct, but in the pin area, the red and green indications are wrong, it's reversed.

Yeah, everything is correctly measured and connected, I've been fixing a lot of headphones recently and I guarantee all the pins are fine, correctly soldered and tested correctly too. I've even re-soldered the cables to each headphone, although it wasn't necessary at all since I was measuring resistance from the plug and 18 ohms there indicate that everything is OK from the tip or ring to the sleeve. Also, 35 ohms between ring and tip indicates there's no short-circuit between the headphones. This is really weird and frustrating .

I hope an expert about this reads my message and tells me what could it be or something I could try to discover the problem. It really shocks me cause all parameters are fine. It's getting on my nerves.

 

OK, hot news, I've finally disassembled each headphone and I've replaced the left speaker by the right speaker and vice versa:

After I swapped them, now the one that is louder is the opposite headphone.

So, I guess the problem is with the speaker itself. One of them is defective (sounds really low). The question is now...

If both speakers have 18 ohm, that means both coils are alright. Then, how is it possible that one of them is not working correctly?

 

For instance, the coil is in a very narrow gap in the magnetic circuit. If the coil is distorted then it can jam in the gap. This might be because the coil has been overloaded and got hot or because of mechanical damage.

 

Sometimes it's just plugged up, not electrical at all... Like wax build up.. ^_^

 

Definitely, it was the headphone (speaker) itself. I've replaced the speaker by another from other headphones and now it's working fine, the sound of both headphones is alright. You always learn something new