Adventurers' Guide for Training:
Buffs help to ease the impact if you're hit while making your own attacks more effective. The following buffs can be used by all classes.
Horn Melody / Drum Melody / Pipe Organ Melody
Guitar Melody / Harp Melody / Lute Melody
Prevailing Sonata / Daring Sonata / Refreshing Sonata
Now, this is important. There are special buffs for each class that are not shared.