Introduction: Adding an Audio Jack to a MUJI Wall CD Player
The MUJI wall-mounted cd player is a nice piece of minimalist Japanese design (it got added to the permanent collection of the museum of Modern Art in New York in 2005).
It has one problem though: the internal loudspeakers are of very bad quality and it's not possible to use it with externals speakers because of a missing audio jack. However it's very easy to add one. This instructable will show you how.
Step 1: What You Will Need
- a female 3.5mm stereo audio jack with switch contacts (normally closed)
- soldering iron and some wire
- a mini drill or dremel
Step 2: Open the Cd Player Case
Remove the 4 screws on the back of the cd player. Open the case and remove the on/off switch as well as the power connector. You'll find that the two speakers are connected with a 4 pin plug towards the bottom of the player. The two black cables are ground, red is right channel, white is left channel.
You'll need to desolder/cut the red and white cables from the speaker and additionally one ground cable (on the photo I picked the one connected to the right speaker).
Step 3: Make Space for the Audio Jack
I used a dremel to widen the slot so that the 3.5mm jack fits through the slot. You probably have to experiment, or you could just use a drill with an appropriate bit. A 2.5mm jack might fit without drilling, but I haven't tried that.
If you don't want to drill the case or prefer a single cable for aesthetic reasons you can also try to use a 4-pin cable which combines power and the audio signal, see the comments further down for more details.
Step 4: Solder the Cables and Fit the Jack
Solder the wires you removed from the loudspeakers to the audio jack. There're usually 5 pins on it: 1x ground, 2x left channel and 2x right channel. Make sure you solder the cables to the pin which is connected to an inserted plug (test it with a 3.5mm solderable plug and make sure you get the polarities (L/R) right). The 2 other pins need to be soldered back to the speakers and will only be active when no plug in inserted (= normally closed). Solder the black cable from step 2 to the ground pin on the jack, and another back to the speaker's ground.
Step 5: That's It!
Before closing the case make sure that the audio jack is sitting nicely in the slot and that everything works. Dont forget to reconnect the on/off switch as well as the power plug. It should work like a normal laptop audio jack: an inserted plug turns the loudspeakers off.