Here is the full list of all 19 BIT.TRIP FLUX achievements.
Chained 200 Beats
Block all Beats during a Subtract Challenge
Beat the game on Normal difficulty
Watch the hidden cutscene
Beat Catharsis in Normal difficulty
Beat Perception in Normal difficulty
Escaped Nether Mode
Register a high score on the leaderboards
Beat Epiphany in Normal difficulty
Achieved a multiplier of 100 in Normal difficulty
Achieved a multiplier of 50 in Normal difficulty
Chained 100 Beats
Get a PERFECT score in Epiphany
Get a PERFECT score in Perception
Get a PERFECT score in Catharsis
Chained 500 Beats
Beat the game, from start to finish, in one sitting
Block 10,000 Beats
Enter Meta Mode in each level