Saturday Soldering and Free Knitting

Back when I used to purchase guitar or instrument cables, patch cords and connector-y bits of all kinds, I’d do everything possible to avoid buying a molded plug. A molded plug? That’s pretty much anything you are going to find these days on any bit of consumer or “prosumer” audio gear.  It’s any kind of connector which goes from the flexible cable part to the plug-into-the-gear part with no discernible change in material. As you trace down the wire from your headphones, there’s usually a transitional bit which flexes and then a more solid bit which ends in the metal jack or connector which fits into the audio, usb or other port on your device.

It looks clean and aero, nice and smooth. But, there’s a tradeoff. The problem with this type of design is that it’s a closed system.  If something fails inside that section – for example, if a voice actor accidentally closes the plug in the door of their booth – you have no way of easily fixing it. It’s essentially made disposable by failure in one of the most frequently stressed parts.

Working with a reasonably limited budget during that aforementioned period of my life, I needed stuff that could be fixed. That meant I bought good cords with complete metal ends – the housing unthreaded from the plug, revealing the details of the wiring.  Cords were always being stressed. They tended to live short, brutal lives. Unless you could whip out the soldering iron and snippy tools and reconnect wires to the leads.

In fact, since I tended to scoop up synthesizers at the trailing edge of technology in those days, I got pretty darned good at making connector cords. I wanted to connect my Moog to my Roland stuff and some other modules. Since Moog used a 1/4” stereo cord for Control Voltage connection (out and in via the same jack), and the Roland bits used 1/8” mono connectors (with discreet CV-IN and CV-OUT connections), and other sound-making bits tended to use 1/4” mono, I cobbled together all manner of cables that spidered throughout that analog system.

All of which went through my thoughts as I stared at the bent connector of my Sennheiser HD280’s.  I’d taken a stutter step as I walked into the booth, caught the trailing headphone cord a bit, and some combination of distraction and deadline had me pulling the door closed behind me at precisely the wrong time. Heard a weird, thin “CRUNCH” and noticed the door not fully closed. Like rattlesnakes and certain mechanical mechanisms, you know precisely what some things sound like, even if you’ve never heard them before. (OK, I have actually done this before…)

The jack had a decent kink to it now, and sure enough, now supplied only mono playback through the right ear.  In all honesty, I’d been hearing the tiniest bit of buzz before that, so I’d probably stressed it before and this recent klutz move simply supplied the connector Coup de Gras.  Alas poor Senn, I knew ye well… But, why the heck did Sennheiser choose to make this with a molded plug?

“Hey!” thinks I. “My soldering iron still lives in the toolbox.  I may even have a 1/4” stereo spare connector…” Turns out I didn’t.  So, errand time.

The folks at the local “real” electronics store – the one that still stocks oscilloscopes, breadboards, radio antennas and all manner of phenomenally increasingly esoteric bits – shook their heads at the possibility of obtaining the gold-colored, 1/4”-tip-threads-off-to-reveal-an-1/8”-tip connector which I’d ganked.  I left with a metal Switchcraft 1/4” stereo plug and unbridled enthusiasm.

However, like playing the bass guitar, riding a bike or voicing characters, solder repair is a skill that needs to be practiced to remain viable. I had dusted off the gear a few years before to solder up the replacement car stereo to the wiring harness connector so I didn’t have to use those nasty press-fit connectors. Other than accidentally clipping rather than stripping one of the wires, it went pretty well, actually. Just had to be a little nimble when working with the last couple (the sharp-eyed among you will notice the yellow wire a bit shorter than the rest). Those had been decent gauge wires, of course, and it was a simple end-to-end connection. The fact that continues to work gave me a bit of confidence.

Taking advantage of a warm afternoon, I leaned into the task at hand.

The first step was getting the thing apart.  The plastic wouldn’t easily peel back, but that was to be expected. A bit of judicious blade work got me down to a clear housing.  From there I could see where the wire-y bits lived and worked my way around removing the rest of the “insulation”

By the time I’d completed that step, it was pretty clear that one of the wires had separated from the connection. The Red wire. Which is weird, because I thought that was the one you were always supposed to clip.

 

Sure enough – as they say, “There’s yer problem!”

The first thing I tried which didn’t work was the Great Repurposing of the Stress Relief Bit.  Clipping the connector clear, the tapered section of the cord caught my eye.  Unfortunately, I did not have an appropriate small file to open up the center of it to allow the whole cable to fit through, and the length of it was a little too much to fit inside the housing of the replacement connector.  Oh well.  Luckily, I’d been trained fairly well at removing cords by pulling on the connector rather than the cord itself. Still, I would have liked putting a spring or something in line where the cord exited the housing.

Pulling that back off, I examined the four wires as they connected to the old plug.  The wires were quite thin, I noticed.  How thin? It turns out they were small enough to slip easily through my wire stripper’s 22 gauge section. Which was the smallest section. At least the existing connections made logical sense – black and blue paired for the ground, and then red and white for right and left.  Except on this specific plug, it looked like the ground wire connection was almost direct to the sleeve section, rather than on the longest “tail”.  Also, the red wire had been connected as the next closest, with the white furthest away.  That was kind of the reverse from what I expected, where the red would have gone to the “middle” – the “Ring” section of the jack itself.

Perhaps if I paused at that minor confusion and sat with it a bit. Maybe thought that through.  Fact is, I got quite distracted by continuing to muck up the actual soldering.  To start with, simply stripping the wires was beyond the capability of my equipment, which forced me to try the blade again as a straight-edge wire stripper.  When that nipped straight through one of the wires, I tried using an ever-so-careful series of cuts with the wire clippers.  Which worked well until I realized that I needed them to be different lengths so they would line up nicely with the solder lugs for the new connector.  Again moving a bit too quickly, I managed to sever two wires completely wrong rather than peel back the thin insulation. So far, my soldering Fu was not good.

A bit of yogic breathing and attempts to reestablish a nice zen sense of detachment later, I carefully worked the blade to re-strip those wires and lined everything up for the solder step.  Which is kind of when I began wondering why it was so hot and how I’d managed to get a front seat in that hand basket.

Everything went wrong. Solder flowed poorly. Wires didn’t stay stuck. When they did, I noticed that I’d melted through the (very, very thin) insulation on the damnably small wire next to the one I’d connected. I caught the cord on the soldering iron which flipped it out of the holder and into my palm tip-first. This was shaping up into a very slow and not particularly funny Three Stooges episode.

It made me realize why, years ago, my dad used to have me help him solder stuff.  On this type of work, you are always about a hand and a half short of what you need. The more I worked, the clearer this became. The plug loved to roll.  The wires enjoyed falling off the table. Nothing wanted to line up. Even my desoldering-fu failed me. When things did line up, I’d have trouble actually seeing the thin wire on the connector. This was very different than the last task I’d completed. (After the project, I would realize I should have picked up something like this.)

Nevertheless, I persisted and ended up tacking things down with tape and spring clips and holding my fingers too darned close to the tip of the soldering iron. All of a sudden it was done!

One problem.

Sometime during a drop, or perhaps when catching the iron tip in my palm, I’d knocked the cover off the wire without noticing it. The metal housing had quietly rolled off the table and out of view.  Until now. (No. There’s no way to put it on after the fact.)

When my mother-in-law was alive, she had been an avid knitter. Occasionally, she’d drop a stitch or reverse something (which is the extent of my knowledge of knitting) and have to undo a row (or several) to get back to the problem. As with all things, her outlook on this was glorious – she called it “Free Knitting” and was happy that she got to do it all over again.

“Free Knitting” it was.  I heated up the connections and pulled the wires off.  Slid the housing back onto the wires and started over again.  But, this time it went quickly – everything lined up with a minimum of fuss and suddenly I was done.

Certainly something to be said for blowing all the cobwebs out with the first attempt.

Threaded things together and connected it to the extension and to the Scarlett, and – to my more-than-slight surprise given the gaffes so far – heard sound in both ears! No buzzes, hums or other distractions!  Huzzah!

Was just about to head back out to clean up when I decided to pull up a stereo file and check each side individually.  They worked alright – Right channel coming through the left side and Left coming through the right.

It seems that I’d chosen poorly in matching the positioning of white & red on the old and new connectors. In fact, I’d ignored my sense that something didn’t seem right. (New mantra – “red-right-ring”).  Since the light was fading outside and the next soldering project I do will take place with that fancy soldering jig, I opted to live with it for a few weeks.  After all, I have other headphones and speakers if I need to hear the right channel on the actual “right” side.

And, that gives me another session of “Free Knitting” to look forward to.