The spring is that bent metal piece. As you push the plug in it initially pushes by the spring and then it catches in the narrow section of the plug to hold it in.
I can't find any evidence that this is common on 3.5mm jacks. If it is, it must be an incredibly reliable design, because I've never heard of a 3.5mm audio port breaking.
There are multiple examples online. Jacks which no longer do stereo but only one channel, or that require "fiddling" with the connection or rotating the plug, or the risks of leaving a plug inside a socket for a prolonged period of time, etc.
And it is really problematic since it is the jack which wears out, which is usually hard to replace; soldered to expensive equipment.
So again: I can't find any evidence that the 3.5mm size of the connector has a spring. The bigger sizes does, but there is nothing online mentioning a spring. Please link to someone with a broken 3.5mm connector due to a spring, if you can find it. I can't.
Also, "there are examples online" != "this is a common thing". I have used dozens of 3.5mm and Bluetooth devices, and I've never had a Bluetooth device that 100% worked and I've never had a 3.5mm device that didn't work.
There are counterexamples in both categories, but my sample size is big enough now that I am willing to bet that the 3.5mm connector is just very well-designed and difficult to damage.
> I can't find any evidence that the 3.5mm size of the connector has a spring
????? I guess I may be using the incorrect word. How do you refer to what keeps the audio circuit closed when no plug is inside the jack, opens it when the plug is inserted, and generally holds the plug inside the jack?
> Please link to someone with a broken 3.5mm connector due to a spring, if you can find it.
https://www.youtube.com/watch?v=kZIWvvl_O7M -- first DDG result. Almost anyone suffering from a loose connection, losing one channel, sound continues to go to the speakers, etc. is suffering from either dust or this.
_In this very article_ there is someone complaining about the plug detect misbehaving which is actually something sensed by the spring (which opens a circuit when the plug is inserted -- on a classic TV this actually opens the normal audio circuit so that you don't hear anything on speakers, on a modern smartphone it just signals the OS).
> There are counterexamples in both categories, but my sample size is big enough now that I am willing to bet that the 3.5mm connector is just very well-designed and difficult to damage.
My dislike comes from a period when I was doing tech support some decades ago. People complain about broken microUSB connectors and the like, but now microUSB is something well designed, since it usually breaks at the cable side (i.e. the cheap side; for example the springs are on the plug). The 3.5 jack is not well-designed since it is usually the jack which wears (at the expensive side).
Keeping something 24/24 7/7 plugged in usually starts to kill the plug in a couple years. E.g. I'm hard of hearing, so I have to keep my headset plugged in all the time in the TV, and a after a couple years of this I start having problems where I suddenly lose one channel and have to go around the TV fiddling with the plug. Eventually this kills the jack (sound always goes to speakers or viceversa), which I've already replaced a couple times...
Why would it wear out? I'm not an expert on material science, but this metal piece is not permanently bending, its just springing back which should just last forever.
The part is made with a specific dimension when plated; the plating wears off -- this produces an undersized spring component and results in a sloppy/loose fit.
it happens more with headphones with a very heavy wire or jacks that get plugs swapped very often.
it can be fixed by carefully using a pick to deform the spring further out, so people tend to think that if that's the case then it must be the spring itself getting lazy.
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