Why the low end gets muddy? Frequency Masking
The kick and bass form the foundation of a track. When they fight for the same frequencies (e.g., 50-80 Hz), the result becomes "muddy" and booming. This is called frequency masking.
The simplest solution is deciding who rules the sub. If the kick has deep sub (like an 808), the bass should sit higher. If the bass holds the low end, the kick should have more click and less sub.
Phase and punch: getting them aligned
Poor phase alignment between the kick and sub bass can cause them to cancel each other out. Even in a loud mix, the "punch" at the very bottom will vanish.
Ensure that at the beginning of the sound wave (the kick attack), the bass wave moves in the same direction. Sometimes simply flipping the phase on the bass track completely revives the low end.
Sidechaining: Not just an effect
Keyed compression (sidechain) is often associated with the "pumping" sound of EDM. But gentle sidechaining is a powerful mixing utility.
Even a fast, unnoticeable gain reduction of 2-3 dB on the bass track right when the kick hits gives the kick room to breathe and adds clarity to the whole track.
A simple low-end workflow
- Decide which element (kick or bass) handles the lowest "sub" frequencies (20-50 Hz).
- Use a High-Pass Filter (HPF) to remove unnecessary low end from all other instruments.
- Apply sidechain compression to the bass using the kick as the trigger.
- Always check your mix in mono. Bass below 100 Hz should be completely mono to avoid phase cancellation.
Aumixys Analyzer features a phase correlation meter and a spectrum analyzer where you can clearly see if your low end is oversaturated or out of phase.