From Wikipedia:

The album is split in two, with tracks 1 through 7 featuring electronic instruments such as synthesizers and drum machines and tracks 9 through 13 using traditional instruments such as the accordion and organ. Track 8 (Intermission) serves as a link between the two halves, beginning with techno-style dance beats before switching to the piano interlude. On the vinyl record version of the album, side A holds songs 1-8 while side B holds songs 9-13, further highlighting the stylistic split in the album.
http://en.wikipedia.org/wiki/A_Fever_You_Can%27t_Sweat_Out