[Sonic Defender]

I had exactly the same problem with an HE-400.
It's most likely the cable from the driver to the mmcx connector inside the headphone.
For someone with a little experience and a soldering iron, it's a pretty easy fix.

Exactly. Virtually guaranteed to be poor solder at the contacts.

 

[BrokeSkoolBoi]

Mine has the same issue if the cable is not curved a certain way from the 6.3mm jack. I think it's a cable issue

 

[Mosabexo]

It's most likely the cable from the driver to the mmcx connector inside the headphone.
For someone with a little experience and a soldering iron, it's a pretty easy fix.

Are there any guides/instructions on how to do that?

I have limited and old experience in soldering and electronics. Even if that suffices, I don't want to miss them up

 

[GREQ]

Are there any guides/instructions on how to do that?

I have limited and old experience in soldering and electronics. Even if that suffices, I don't want to miss them up

The first step is troubleshooting the cable.

Disconnect the cable from the right channel, and plug it into the left side of the headphone and play music through it.
While listening, try to gently apply pressure to the cable at different angles to make sure that there is always continuity.
Do the same for the Y-split and the plug joint area.

If there are absolutely no moments of intermittent audio then it's safe to say the problem lies within the right capsule.

Next, open up the right capsule.
- Pop off the grill retainer ring (very easy to do without damaging the headphone in any way)
- There are 4 tabs holding it in place at the 'corners' as if a square was drawn onto the grill
- The grill should simply fall out
- Observe the cables connected to the mmcx connector
- it should look similar to this (hopefully less dusty )

One driver cable is soldered to the tiny 'right channel' connector prong inside the connector. (cable on the right in photo)
The other driver cable is crudely soldered to the outside 'ground return' connector. (cable on the left in photo)
Just moderately pull on them and see which one is loose.

Honestly, if the problem is a loose connector on the inside of the connector, you might need a very thin soldering iron bit and a bit of patience.
I think I even managed to repair this with an average size bit.

Before attempting a repair, apply masking tape (or duct tape, etc) over the driver.
You don't want any hot droplets of solder or flux getting onto the diaphragm.

 

[buke9]

Just to avoid confusion the connector is not MMCX but SMC just thought I would throw that out there. Solder irons are not that expensive and easy to use with a little practice. I agree with @GREQ find one with a thin tip or one that has replaceable tips and use one of the thinnest ones should not cost more than like $20 I got a Stahl that has a stand and variable temp and tips for under $50.

 

[GREQ]

Just to avoid confusion the connector is not MMCX but SMC just thought I would throw that out there. Solder irons are not that expensive and easy to use with a little practice. I agree with @GREQ find one with a thin tip or one that has replaceable tips and use one of the thinnest ones should not cost more than like $20 I got a Stahl that has a stand and variable temp and tips for under $50.

Thanks for clearing that up... even as I wrote it I wasn't 100% sure I got the connector name right

 

[buke9]

Thanks for clearing that up... even as I wrote it I wasn't 100% sure I got the connector name right

Not a problem just wanted to avoid confusion for the poster that was getting into something they hadn’t before as it can be a little nerve racking for a first timer.

 

[Mosabexo]

Thank you all for the explanation, I really appreciate it!

Ok, so I did open it up after confirming it isn't the cable, but the wires inside are not loose. I tried pulling on them and applying pressure on each end, but nothing came off. Granted I wasn't forcefully trying to taking them out but I wasn't gentle either (i.e. started pulling off gently and then with more pressure). See pics below if it helps:

Spoiler: pics

Can a faulty driver work completely die and then suddenly work as normal only to die again a few mins after?
Should I get a multimeter now and test out the wires on the pics? If so, how would I know which is +/- ?

Edit: When I tried putting the grills on again, I missed the circle edge a few times the magnet on the driver pulled the grill metal in so I had to pull the grills out each time. Was not aware that that could happen. Hopefully I didn't destroy the driver for good now lol .

 

[Sonic Defender]

Thank you all for the explanation, I really appreciate it!

Ok, so I did open it up after confirming it isn't the cable, but the wires inside are not loose. I tried pulling on them and applying pressure on each end, but nothing came off. Granted I wasn't forcefully trying to taking them out but I wasn't gentle either (i.e. started pulling off gently and then with more pressure). See pics below if it helps:


Can a faulty driver work completely die and then suddenly work as normal only to die again a few mins after?
Should I get a multimeter now and test out the wires on the pics? If so, how would I know which is +/- ?

It could still be the solder. If you can find out how to go about it you would want to remove all of the old solder, clean the surface and re-solder. Might be more than you want to get into though. I have always been lucky and never had this happen yet, but I have read about it many times and encountered poor solder in other electronics.

 

[Mosabexo]

It could still be the solder. If you can find out how to go about it you would want to remove all of the old solder, clean the surface and re-solder. Might be more than you want to get into though. I have always been lucky and never had this happen yet, but I have read about it many times and encountered poor solder in other electronics.

Interesting. Do you think a poor solder would alter/hinder functionality even after years without any problems? I'll definitely try every fix

 

[Sonic Defender]

Interesting. Do you think a poor solder would alter/hinder functionality even after years without any problems? I'll definitely try every fix

I know that it can become what a technician friend described as "dry". He used to own a stereo repair shop close to Wembley Stadium and he told me that dry solder joints were so common that he almost assumed them in many situations. Again, I could be wrong, but I have read about many people who remove old solder completely, clean up the surfaces and re-solder and their problems are fixed. Not sure if that will be your experience, but if it is something that you feel you can do easily enough without risking harming your diaphragms at least it is a possibility to consider.

 

[Sonic Defender]

Saying that, I would be remiss if I didn't say that it could easily not be the solder at the cup connector. Good luck and perhaps reach out to HiFiMan and see if they could offer up any thoughts as to what may be happening.

 

[bagwell359]

I know that it can become what a technician friend described as "dry". He used to own a stereo repair shop close to Wembley Stadium and he told me that dry solder joints were so common that he almost assumed them in many situations. Again, I could be wrong, but I have read about many people who remove old solder completely, clean up the surfaces and re-solder and their problems are fixed. Not sure if that will be your experience, but if it is something that you feel you can do easily enough without risking harming your diaphragms at least it is a possibility to consider.

I learned "cold" solder joints as opposed to dry - just nomenclature. I spent a few college year summers and winters soldering (touch-up, wave), etc. and more time looking at dry/cold joints. You really want a shiny silver appearance, but no big blobs. Sometimes its as simple as they didn't use solder paste (you get a grey finish), or they didn't heat it long enough (pin holes and/or grey). I basically don't trust anybody else's work and if its looks funky - it's going to get redone. As far as planars - cover the membrane well, because sometimes solder can spit and you don't want that landing on the membrane. Also where the connection goes to the membrane it's usually very thin gauge and having the iron hot can melt the membrane even like 2" away - I wouldn't go near that unless it was 100% necessary - and if so, lower the temp - not sure to what - depends on conditions, maybe you can look it up.

Get an iron you can adjust the temp on, that has good reviews. Use a "heat sink" whenever you can, get good solder (w/ silver is the best, but vent very well - the fumes are very toxic). Even regular solder fumes you shouldn't breath in - windows open and maybe a small fan too. Also - don't work with it when you are tired or pissed off - fine motor control usually suffers.

 

[BURNART]

So which pads are the best besides ether c?

 

[GREQ]

So which pads are the best besides ether c?

ZMF Ori.