The headphones are not working, I think the culprit is this button, I’m not sure what it does, I guess turn them on and off? I wanted to connect the cables directly bypassing this , but I saw there are two resistors, can I do it ? Any ideas on how to fix this? If someone has a pdf of the service manual would be great! Thanks! @Valentin
It's curious the service manual does not show any switch: https://www.petervis.com/manuals/sony-mdr-4l1/mdr-4l1.html Is that switch latched ? If so, can imagine its purpose is to bring the volume down when resistors are connected and normal when they're bypassed. Would go ahead and bypass the resistors.
Mmmm I think it’s a slight different model, the one in the manual is the 4l1 this is the 4l1s. After more testing and I disassembled everything, I discovered that the button actually works and the problem is one of the speakers that its done and the was cable broken near the speaker. I cut the cable a put 2 new temporary speakers and it works. Now I need to find 2 replacement speakers that fit, I found this ones https://a.aliexpress.com/_EGzxJqY the ones 23 mm, the specs are not the same, mostly the watts, would it work anyway, or can you suggest me another one? thanks!! ps: the switch turns off the audio only when pressed.
From the link, there's only one driver that looks like a headphone driver (see picture attached) and it's not the right dimension. Rest of them are the type with hard membrane, higher power lower impedance. These are usually used in things like walkie-talkies where audio quality is not important just to be small and have rather loud volume. Don't have any source to recommend, but you need the drivers with transparent soft membrane for headphones.
