I oringally got the idea when i saw a very nice but very expensive iphone amplifier and it struck me that a low tech alternative was readily available not too far from our front door
I apologise in advance as some of the photos are a bit grainy
Step 1: Tools and Materials
Dremel with cutting attachment (but a hacksaw will do)
Step 2: Marking It Out
You want to mark it roughly 2/3 thirds to 3/4 quarters across the top of the cone down to just above the quarter way mark close to the narrowest end of the cone. the gap should be roughly 1.5 cm wide and at an angle so that the speakers at the bottom of the phone are aimed down the cone.
Note: make sure your marked cutting area is running parallel to the flat edge at the base of the cone.
Step 3: Cut It Out
Step 4: Additional- Wire It Up
Step 5: Finished
Feel free to give it a lick of paint if you wish to
This instucable was in no way endorsed by apple but is by the "Give a cone a home" charity.