Replace 3.5 mm AUX with USB

Question

This might be a touchy subject, but bear with me. I have a 2.1 speaker set which has typical 3.5 mm AUX input and output. The problem is that sometimes the left and/or right audio channels cut out and I have to jiggle the cables to get them to work again. I've tried duct taping the cables in certain positions, but the problem always reoccurs eventually. I tried buying a better quality aux cable, but the problem seems to be with the female connectors on the subwoofer. It's a massive annoyance.

It is for this reason that I am a shameless supporter of the death of the 3.5 mm connector. I know, I know. Hate me if you must. Call me whatever names come to mind. All I know is that I am currently listening to Zeppelin's 'Ramble On' with one audio channel and it's torture.

I think I may have a solution, but I'm not sure if it's viable. On the inside of the sub is a PCB with a couple of female 3.5 mm jacks soldered on that look like this:

I am wondering if I can remove them and replace them with something similar to this:

Is it just a matter of soldering certain connections together? Or would I need a DAC and/or other components? What gets soldered to what? It's a pretty cheap speaker system so if something breaks I'm not too worried.

I have very little electronics experience, but I would like to make a small project out of this anyway. I appreciate any tolerance of my unpopular views on tech. Go easy on me.

Answer 1

Assuming this is a line-level signal, sure, you could replace the 3.5mm jack with a USB connector. But why?

It would likely be a lot simpler to simply repair or replace the existing jack. It my simply be a bad solder joint to the board. If the jack itself is bad, you can probably find an exact replacement with a bit of looking. Even if you can't find one that fits the existing footprint, it's still probably going to be easier to fit a new 3.5mm jack even if you have to do a bit of bodging than to try to fit a USB connector there.

The 3.5mm TRS connector has some drawbacks, but it's been the standard for this sort of thing for a long time with little trouble. A bad experience with one device doesn't really warrant such an extreme response.

If you do have repeated problems with cables failing, you might want to look for a cable with a right-angle connector at the speaker end. This may reduce the strain on the connection and improve the lifespan of both the cable and the speaker connection.

Answer 2

Using a standard usb connector or cable or a non usb system is asking for trouble. Yes you could use the connector but just don't. Last thing you want is somehow plugging it into a live usb jack and something breaking.

You could add a usb audio card internally, connecting it's analog out to the speakers audio input, and connect it to your computer using a standard usb cable. This would bypass the need for the 3.5mm connector and cable. Or replace it with a Bluetooth audio receiver. Same exact change.

The other option is replacing the audio jack connector.

Answer 3

If you're determined to replace the connector, change it for something more durable, like a binding post (https://en.m.wikipedia.org/wiki/Binding_post)

If you're looking for something compact a USB could work, I don't think you'll cause any problems if you one day plug your memory stick into it :) - the process would essentially be to work out which connectors on the board are L R and GND, connect them with wires to the connectors on the USB (the USB module's connectors are in a different place to the jack so you'll need wires for reasons of flexibility) and ensure when making up your USB-to-jack cable that you wire up to the same pin. You arbitrarily decide this order when soldering the USB socket in. Just bear in mind that the connectors of a USB plug are upside down relative to a USB socket when connected (if you were to dismantle both, hold them as if you were about to connect them but then turn one of them over so you can see the gold connectors on both plug and socket, the rightmost connector on the socket contacts the leftmost connector on the plug - this is different to a jack connector where "furthest in connects to furthest in" etc

For my money I think I'd try use an Ethernet style RJ45 first because making the patch lead up would be easier/require less soldering and heat shrinking (but then I already have a crimp tool)