Bands
AudioLink splits up music into four different bands. You can select which of the four bands an effect will react to.
Bass
The low end: kicks, bass etc. Very visceral feeling and great for AL usage.
Low-Mids
Stuff like vocals, snares, and most instrument fundamentals are here.
High-Mids
Contains harmonics of low-mid fundamentals. Some percussion lives here too. Harmonic content starts to get lost here
Highs (aka treble)
High fundamentals and percussion noise such as hi-hats. Minimal harmonic content here.