Lyric discussion by NUMBER 4 

Call me "desensitised" to the TV world, but what does the term "TEST FOR ECHO" actually mean?

@NUMBER 4 It has nothing to do with TV. It refers to making noises to test if something is hollow (e.g. making noises in caves produces echo because of sound bouncing back from the walls). In this context it means testing if your head is hollow (aka stupidity)

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