WARNING!!! THIS MOD WILL VOID YOUR WARRANTY AND YOUR CONTROLLER CAN BE DAMAGED IN THE PROCESS. I TAKE NO RESPONSIBILITY FOR EITHER OF THESE, NOR AM I RESPONSIBLE FOR YOUR PARENT'S COUCH CUSHIONS. PROCEED AT YOUR OWN RISK.
Side Note: You will have to enable voice to be played out of your tv's speakers. This can be done through preferences in the xbox 360 dashboard.
Dremel or drill with small drill bit
Small flat head screw driver
Hot glue gun
razor blade (optional)
Xbox 360 controller (any type)
Cotton or soft foam (optional, I used toilet paper)
Small Microphone (I used one from an old laptop, but any small mic should work.)
If you can't recycle a microphone from old tech this mic should work fine.
Step 1: Disasembly
Once the screws are out pull the top half of the controller off while the buttons are facing the ground. This will prevent the buttons from falling all over the floor. You can tape the buttons down from the top of the controller, but we will be removing them temporarily anyway so I skipped this.
Pull the motherboard out and disconnect the tumble motors.
Step 2: Controller Motherboard Preparation
Make sure that you only desolder the eight small pins in the middle and leave the two large pins on the sides alone. The two large pins are for the batteries.
Side Note: Removing the headset jack eliminates your ability to use the keyboard add on with your controller. I will cover how to fix this at the end of the tutorial.
Step 3: Mic Placement
Now it is time to drill the mic hole. I prefer to use a dremel with a small drill bit, but a regular drill will work. Just make sure that you are very careful not to damage the case. The hole does not need to be that big at all, in fact I like to keep it pretty small the reduce the chances of stuff getting in to the controller, such as liquid.
OPTIONAL: After I drill the hole I take a razor blade and shave around the inside edge of the hole for cometic reasons.
Step 4: Adding the Mic
BEFORE we glue the mic down it is a good idea to test the controller first. The safest way to do this is to put the motherboard back in the plastic casing, without putting the smaller plastic piece, between the two halves of the case at the bottom, back on. Just let the mic hang out. Log into xbox live with the game of your choice and start speaking. Depending on the game you are using there should be some type of indicator to tell you that you are making noise. For better testing asking someone to describe the quality of your voice to you. Test this with the tv volume at its normal volume and remember how sensitive the mic is when picking up noise while holding the controller the way you normally would while playing. If they can't here you and your noise indicator isn't showing that you are making noise then you either soldered the pins wrong or the mic that you chose is broken. This is why this is a very important step! ;)
Now it is time to glue. Depending on your controller and/or mic placement preference glue the mic to the motherboard directly underneath the top half of the case where you drilled the mic hole. Be sure to not use to much glue, but just enough the hold the mic in place. Also be sure to put glue on the bottom side of the mic were it's terminals are in order to insulate it from the circuitry of the controller motherboard.
Side Note: In my first internal mic project I glued the mic the the plastic of the controller case but this proved to be a pain reassembly and disassembling the controller later.
Step 5: Re-enabling Keyboard Attachment Use
OPTIONAL: Depending on how you ran the wiring for the mic, you may or may not want to use a cutting tool, like a dremel, to remove the middle section of the headset jack rather than use removing the four middle pins. Instead of removing all of the plastic and dividing the headset jack into two pieces you may want to just cut the small tunnel in the middle into a trench, so to speak.
Step 6: Finishing Touches
Once you are happy with your advanced noise reduction system, you can reassemble the controller by putting everything back in place and reinserting the screws.
You should now have a xbox 360 controller with a fully functional internal microphone. Don't forget to go into your xbox 360 preferences and change voice to play audio through tv speakers, otherwise you won't be able to hear anybody else.