This song is NOT related to the diff name "Uncompressed Fury of a Raging Japanese God" at all......
The lyrics of this song can be interpreted in Japanese as "if you want to achieve something, do it recklessly" or "Do not kill yourself" and the songs creator refers to these interpretations of the lyrics too.
Also the diff name doesn't make sense in relation to the title either because, "天樂" is not a word in Japanese.
However if I had to imagine its meaning/interpret it myself, it would consist of 「天(heaven)」 and 「樂(should be 音楽/music)」 so "someone who has frustration sings hard as penetrate the heaven" should be fine for interpretation.
fyr:
http://dic.nicovideo.jp/v/sm7918983