[dougms3]

New here, I took a flyer on a set at an auction and they were dead. Nothing. I’m going to play around with some different cables but I’m afraid they may be beyond my help. Gonna try. I was so excited.

If it's dead, the voice coil wires will need to be resoldered.

 

[bryancl]

That’s what I was thinking from reading the thread. I wish I had the skills for it, might have to ask one of the pros here do it!

 

[ScubaMan2017]

Here are detailed descriptions (I totally understand if you don’t read this, it’s super long):

1. Pull off the ear pads
   1. Pry them off however you can, they snap in and seem pretty durable.

1. Detach the driver assembly (Torx T6 screws)
   1. The assembly should somewhat fall out. You can push it out by pivoting the ear cup if it doesn’t pop out on its own, although it will still be attached by the wires to the jack.

1. Detach the input jack (Phillips 00 screws)
   1. These are tiny as eff and I recommend putting them in a baggie or something.
   2. The jack sits on tiny indexing tabs, pull outward to pop it off, then upward to fully remove it.
2. Detach the magnet (Torx T10 screws)
   1. When you pull off the magnet, take care to move it straight away from the assembly. If you pull it off at a weird angle, or rotate it, it could potentially bump the voice coil, which is very delicate.
   2. So far as I can see, there’s no good way to precisely center the magnet when you re-attach it later when reassembling (nor are they precisely centered to start). The only reference points are the screw holes, so when that time comes, just center it as best you can visually and tighten the screws gradually.

At this point, you can either try to find the break and only repair the one spot, or say screw it and replace both ends, which is usually what I end up doing (or all 4 connections if doing both drivers). I figure if one connection fails, the others might also, and sometimes it’s just hard to tell which end has the break to begin with. Before the soldering madness, a photo of the goop, and one of a typical snap.

1. Clip the wire ends just beyond where the black goop ends. We want as much red voice coil wire as possible, but the goop doesn’t come off easily when tinning, and the wire’s far too delicate to scrape it off, so just trim it all up to that point.
2. Tear off the wire end from the solder pad. Also scrape/tear off the black goop on the solder pad. There’s also a translucent layer of god-knows-what on top of the solder, scrape that off as well (I grab it with tiny pliers).

1. Remove the solder from the pad, I suggest solder wick with some flux. I don’t recommend a solder sucker, as the jostling motion from that runs the risk of bumping the nearby voice coil.

1. Cut off some some replacement wire. I use about 11mm of 26.5 gauge Cardas wire. I strip it of it’s insulation, and then take one individual strand. Before, I had tried the full bundle, or even a single larger gauge wire, and realistically they worked fine. It seemed logical to me, though, to match the replacement wire as closely as possible to the coil wire. That keeps its stiffness more similar, and since it does move around with the driver, its mass and stiffness could matter? It does mean it’s harder to work with though.

1. Tin both ends of the replacement wire.
   1. If you have enamel-coated wire like I did, just pick it up with tweezers, and put a tiny amount of flux on one end. Melt some solder on the tip of the iron, and hold the fluxed end of the wire in the solder until they bond. At first, the wire will just push the solder out of the way, but after a bit (and maybe some more flux or a higher temperature setting) it should coat with solder.
   2. Do the same for the other end of the short replacement wire.

1. Tin the end of the voice coil wire.
   1. This parts is way more delicate, and has the added bonus of really sucking if you accidentally melt anything nearby, like the coil itself, or the driver surround.
   2. Same process as above, put a tiny amount of flux on the trimmed end of the voice coil. A toothpick works well as an applicator.
   3. Tin the tip of the wire, taking care not to bump anything, and also not to overheat and burn the wire itself. I haven’t done that yet, but it’s so dang thin that it’s probably possible to toast it. Reapply flux if necessary.

1. Solder the replacement wire to the solder pad.
   1. Apply flux to the pad. Use a small amount, as it sputters, and can coat nearby things that aren’t really cleanable (like the driver and coil).
   2. Use tweezers to hold the replacement wire, and put some solder on the iron, them solder the wire to the pad.
      1. At this point, the other end of your short replacement wire should overlap the new end of the voice coil by a couple or few millimeters. There’s usually not much length to work with, so you might have to nudge things around with a toothpick or the tweezer tip.

1. By far the hardest part for me until I did several of them: solder the wire tips together.
   1. Using a toothpick or tweezers, gently push the wires around until they are bumped up against each other, and they stay pressed against each other on their own. This can be hard, as they often spring apart. If one bends slightly to the left, for example, and the other to the right, if you nudge one to the opposite side, they’ll sort of press against each other just by virtue of their springiness, if that makes sense at all (attempt to show in photos).

1. Apply a teensy amount of flux where the wires overlap. You don’t need much at all (you could probably get away without any on this spot but I recommend it), and it can sputter, so you don’t want more than necessary.

1. Put a tiny amount of solder on the iron tip, and solder the wires together.
   1. Often, when removing the iron, one of the wires will pull away with it, and detach from the other wire. It can take many attempts, and each attempt puts more heat in the tiny coil wire, which we want to minimize.
   2. For this, I recommend using about as low of a soldering temperature as possible, if you have a variable temp iron. I put mine on the lowest it would go, which is 205ºC/400ºF. That’s enough to melt the Cardas solder I use (good stuff, that, and nice low melting point). The tiny (already tinned) wires will take to it immediately. If any of the ends are not tinned, you have to hover there for a while and it increases the chance of something going wrong.
   3. I’ve found the technique in removing the iron to be really tricky. Pulling the iron straight away from the wires often doesn’t work well, as it might pull one of the wires with it as it sticks to the solder blob, leaving the other wire hanging in the air. Best is to briefly touch the wires with your iron, then move longitudinally down the wire with your iron. Once you move the iron past the solder junction you can pull away gently. Basically, the more perpendicularly you move away from the wire, the more the wires tend to pull apart; the more parallelly (the internet assures me that’s a word) you pull away, the better your chances. First, a photo of the small amount of solder I use, you don’t need much. You’ll notice in the second photo that it doesn’t look like there’s much solder there at all on the wire. That is true, that’s mostly since it’s just a small wire to bond to. In a way, this is good. It means that there isn’t some big clumpy mass to flop around as the driver oscillates. Also, each one of these I have stress-tested afterward by blasting some really good music through them with big bassy moments (for reference, I use Bilo 2.0 by David Maxim Micic, it’s an flipping amazing album), and each one has held just fine.

1. Clean up any flux on the solder pads with a Q tip with a small amount of isopropyl alcohol. It’s not critical, but just nice to do.
   1. Don’t attempt to clean off any residues on the solder joint where the wires attach, they’re just too fragile. For example, if you look closely in my photos, you can see what looks like a tiny strand of cotton or something hanging off of the solder joint. If that happens, I just leave it there. I tried once to gently wipe stuff like that away with a Q tip, and the wires immediately snagged, and it was damn difficult getting it off the Q tip without breaking things. 0/10, would not try again.

1. Reassemble.
2. Rock the **** out!!!

Thanks for reading my absurdly long post, and please let me know if you have any questions or suggestions! This stuff is really fun/frustrating, and rewarding/defeating! Choose your own adventure!

2 year old reply = this is a fantastic post! If you’re still monitoring this thread, @LuthierJeff , I appreciated the content. Gives me the inspiration to repair my bloody Sony MDR7510 cans!