Here is the full list of all 24 Klang achievements.
Survive the Limbo encounter
Defeat Sonus.
Survive the Death Angel encounter.
Defeat Bazz.
Master all Shufflejumper tracks.
Make it out of the forest.
Finish the prologue.
Score a 9x multiplier.
Find a pirate token.
Score your first S rank.
Score your first SSS rank.
Unlock all pirated music!
Go the wrong way...
Dodge Sonus' beam during the prologue.
Defeat Sonus during the prologue.
Listen to a song in the Pirate Bay.
Listen to the last song on the list in the Pirate Bay.
Welcome to the end!
SSS rank it all!
Finish with a track score of 250 or higher!
Finish with 0 deaths!
Finish using the fastest path possible!
Finish in less than 1 hour with a 150+ track score!
Master Shufflejumper 4 early by riding the wind.