 " Mothers of the Disappeared " runs for 5 : 14 ( 5 minutes , 14 seconds ) . It is played in common time in a key of A. The song begins with the sound of rain hitting a roof , which fades in over the first fourteen seconds alongside the bass and a processed drum loop beat by Mullen which <unk> in the background . Thirty @-@ two seconds into the song , Mullen 's drums enter , playing a sporadic beat every four to five seconds . At the fifty @-@ second mark the drums play a more regular beat , and the Edge 's guitar , accompanied by Eno 's synthesizer , enters . The first verse begins at 1 : 28 , and introduces the chord progression of A5 – <unk> – F ♯ m – D – A5 , which is played in the verses . At 2 : 41 Eno 's keyboards enter , and the song begins to follow a D – D5 – A5 chord progression , while Bono begins falsetto vocals . The second verse then begins at 3 : 01 . The lyrics end at 3 : 37 , and the song returns to the chord progression of D – D5 – A5 . The harmony gradually grows in volume until 4 : 33 , at which point the song enters into a <unk> ; the keyboards come to a finish and the guitar returns to playing A notes before fading over the next eight seconds alongside the bass . The synthesizer , drums , and drum loop conclude the song , fading out slowly over the last thirty @-@ one seconds . 
