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SoundBlaster Jam 3,5 mm Jack Mod


In this guide you’ll learn how to modify your SoundBlaster™ Jam™ headphones (which from the factory are USB/Bluetooth™ only) to use a 3,5 mm audio jack.


We’ll be working on the right headphone only (it’s labeled R on the headphones, just above the headphone itself).

First of all, remove the foam earpad. It’s as easy as removing it from its hole.

These headphones have some weird—although I don’t think proprietary—screws. I used a spiral screwdriver bit, the one with three sides. I don’t think you’re supposed to use it, rather, you’re supposed to use a triangle bit—I have one, but it’s of a larger size.


Figure 1: One of the three screws used to hold the headphone together.

After the plastic part with the speaker (the one you just unscrewed from the headphones) is removed, lay it off to the side (while being careful about the thin cables leading to the speaker). Then, use a small flat head screwdriver and gently pry up the plastic covering the PCB. Slide it out, and now the real fun begins.

Soldering, Part I

Find (or buy) a 2-wire audio cable, or just take some spare cables you have laying around. Take out your soldering iron, some solder, and wait for the iron to heat up (if you don’t have a transformator soldering iron).

Now, take a look at the PCB.


Figure 2: The PCB, zoomed on the solder pads we need to solder to.

You see the two solder pads labeled “SL+” and “SL-” (if you don’t, they’re right above the black and red wires)? Correspondingly they are the signal and the ground pads. This is where you need to solder your audio wires, but you also have to make sure the two wires that are already there don’t get desoldered. You could also hijack both the cables that are already soldered to the pads, but it’s not a very durable solution, although being easier.


Figure 3: My shitty soldering job. Reminder that I’m using one of the old USSR-type soldering pistols.

It should essentially look like the picture above, except you should try and make it a bit neater.


Now, take the plastic you have pried out of the headphones (the one taken out with the flat-head), and drill two holes in it—either using a drill or perhaps a scalpel, like I have—one for each audio cable. Pull the cables through, put the plastic back in place and it should look like this.


Figure 4: Holes.

Soldering, part II


Figure 5: The wire on the left (-) is the ground, and the one on the right (+) is the signal.

Now you need one more 2-wire audio cable, and you need to solder it to the speaker (the speaker is located in the plastic part where the screws were). Thankfully, the speaker (just like the PCB) clearly labels which pad is for the ground and which for the signal. Also, instead of soldering your audio wires to the pads that already have wires soldered on them, solder them to the pads right next to them—they’re there for additional cables, and that’s exactly what we’re doing.


Figure 6: This is how it should essentialy look like.

Now, it’s time to take out a 3,5 mm jack, either one that you salvaged, or one that you bought. Of course, instead of an AUX jack you can instead install an AUX port, if that’s what you want. However I myself prefer AUX jacks, and that’s how I modified all my headphones to be.

If you take a look at a bare 3,5 mm jack, you’ll see that it has two solder pads—the one at the top (with the pointy bit of the jack down) is the left channel (L) and the one on the bottom is the right channel (R). The ground is simply soldered to the area above the topmost black ring.

Now, solder the wire from the SL+ to the L pad on the jack, and the wire from the + terminal of the speaker to the R pad on the jack. Connect the two ground wires (the SL- and the - from the speaker) and solder them to the area above the topmost black ring.


Figure 7: All soldered!

Remember to not make your wires very short, because then you might have to tediously solder over and over again. I had my wires too short, and I had to solder yet another wire.


Figure 8: What a mess.

Case Modification

Now, between the two black screw holes inside of the speaker assembly, remove some plastic using a scalpel. In fact, remove it all, so the side is flat with the base.


Figure 9: This is where you should make the plastic. The 3,5 mm jack will fit in here.



Figure 10: Testing process.

Now, before we glue it all together, test your headphones. Not only test if you can hear anything, test if the channels are correct (i.e. test if your headphones are correctly stereo—search for a stereo test on YouTube®™). If it all works, we can go on.


Dab some super glue on the hole you made with the scalpel (in the speaker assembly plastic) and place the audio jack inside of it. Wait till it dries, and voila.


Figure 11: Gluing.


Put the speaker assembly back, screw it all on, and all the hard work’s done.


Figure 12: Reassembled.

Now, tape up the area around the jack, because of the solder it could be abrasive and damage the foam earpads (not that we’re not going to damage them soon).


Figure 13: All taped up.

And if that’s done, reattach the foam earpads, and using the audio jack itself, make a hole in the earpad.


Figure 14: Finished product!

Enjoy! You now have headphones that work with a normal jack, a USB connection, and Bluetooth™.


Figure 15: It’s invisible.

Author: zd