Summary

pipe from here http://www.thingiverse.com/thing:39443/#files

small holes on top for sound to come out and small holes on both side of iphone hole should work for iphone 4, 4s. and 5 versions a bit.
made with 3 pipes like a rusian doll to remove all thin walls.
http://youtu.be/s1y-m7Y5hGY