Erik Johnson loves the way his old hand-cranked gramaphone amplifies sound. He found a way to feed the sounds produced by his iPhone through it:
So I’ve been thinking about how my old Victrola works by passively amplifying the vibrations from the diaphragm through a simple box and how I can control the volume (somewhat) by opening and closing the doors. I said to myself, “Self, I bet that would work as a passive iPhone amp too.” I was thinking about how to get the iPhone speaker at the beginning of the sound's path, thinking it was gonna be complex like removing the arm of the Victrola. I didn’t want to damage the old girl. And then, Eureka! I saw that the diaphragm and needle part of the arm come right off easily, revealing a simple way to get the iPhone sound in. After about an hour, I had this baby working.