The following are different analyses, done by Hana about the music of FMA...

Unerasable Sin by Nana Kitade
  This piece is played in a very fast and fun tempo. Since the song falls into the category of J-rock we can already assume we know the medium or the instruments used: drums and guitar (bass guitar in this one). Although the piece begins at a moderate tempo with synthesized music (police sirens, etc.) it continues to remain pure rock. The music remains in 4/4 cut time despite the transition in tempo. It is categorized as either modern rock or alternative and has an A-A-B-B form where there is no base note and is wholly homophonic. Kesenai Tsumi is very expressive programmatic piece.
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Melissa by Porno Graffiti
  Melissa is one of those songs you just have to jump around with, lol. The piece once again includes synthesizers, but I can hear an electric guitar along with a constant thumbed tambourine and drums. To an extent, the piece can be categorized under J-Pop, but it may also be classified as J-rock. The form is A-B-A-C and again I can not find its tonality but it is homophonic. The tempo is pretty moderate and stays this way the whole time. An echo can be heard constantly (which gets really annoying when your sisters sings the echos XD). It also seems to have a rap-ish sound to it which helps with its dynamics along with the introduction of the bass guitar in the C-part.
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Rewrite by Asian Kung-fu Generation
  For sure, this piece would be classified under J-rock. The form is A-B-C-B and it is homophonic cut-time. The tempo changes for each part of the song and finally ends as it started. Rewrite is obviously by a bass guitar, electric guitar, and drums. It is very much like what people around here call Punk Rock (I say 'people around here' because the definition of "punk" is a controversial issue). This song does not use synthesizes unless you want to count any devices that illuminate the sound quality or timbre of the instruments.
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