A Disappointing Reality, of Manufacturing Today

In This Posting, I wrote how I had my “LG Tone Pro HBS-750″ Bluetooth Headphones around my neck, with the ear-pieces attached to the end of the collar-piece via magnets, that I put my head down on a cushion for a moment, and that immediately, I had a kink in the very thin cable that connects the left ear-piece to the collar-piece.

This happens because the very thin cable has as outer tubing, a rigid kind of material, which develops kinks especially easily. Rigid tubes will form kinks instead of bending.

The headphones have not stopped working yet, but I am very worried by how long it may only take, until that happens. Right now it strikes me, that the average lifespan of a pair of Bluetooth Headphones is 3 days.

Inside the ear-pieces, there are driver coils, which produce variable thrust, in response to voltage and current changes, and which move slightly, across the magnetic field lines of permanent magnets. These driver coils have traditionally been made out of enameled wire.

The way devices were manufactured a long time ago, there would be some kind of contacts inside the ear-pieces, which transfer the current from the enameled wire of the coils, to thin braided wire in the cables that connect the ear-pieces to the collar-piece.

What I find very disturbing, is the degree with which companies have cut corners. The companies have spared every expense. By now, the enameled wire of the coils is merely extended down the tube, that connects the ear-pieces to the collar-piece. That is all.

What this means, is that instead of having changes in the series resistance, the probable mode of failure will eventually be a break in the enameled wire. And when that happens, there will be absolutely no way to repair the damage, other than just to spend another $ 90, and to buy a new set of BT headphones.

Because of a tiny little wire, that was never designed correctly in the first place.

Dirk

(Edit : ) Also, the free end of this one enameled wire is just soldered into the circuit-board, on either side of the collar-piece, so that an earnest attempt to replace the whole ear-pieces, requires that we use a soldering iron. After we undo the trick, which secures the thin cables to the shroud of the collar-piece mechanically. And it just so happens, that not any type of soldering job will be good enough. The soldering iron needs to be low-wattage enough, that it is safe to use with modern, small-component circuit-boards. It is possible for some people to be able to do basic soldering jobs, but not ones at low wattage, on the tiny circuits of modern circuit-boards.

I should just point out, that this particular problem is not specific to LG. For example, I have owned Sony, wired, over-the-ear headphones for a long time, where for one reason or another, the outer tubing on one of the cables has slid, and has exposed the enameled wires underneath, right at the edge of the headphone where there is a lot of wear and tear.

But on those age-old Sony headphones, that enameled wire next lasted for a long time, and never really broke.

(Edit : ) There exists a recent advancement, which makes the concept more feasible, and which did not exist in that past era, which I still use as a reference-point. It is possible to manufacture an apparent wire which looks at first glance like a single, enameled wire, insulated with a transparent resin, but which under closer inspection, is braided out of several, even-finer wires. Therefore such a supposed wire, is also not truly a wire.

This is one of the improvements which also help explain, why the enameled, braided wire does not fatigue close to the driver coils, which deflect back and forth 20,000 times per second.

My Sony headphones used that, and it would only be fair to assume, that my LGs also use that. But, because the wires of my LGs have not been exposed (so far), I cannot be 100% certain.