The equalizer is the most important audio tool.

It is used to correct the frequency balance of each instrument and to create space or consistency between different instruments.

Frequently asked questions are:

· When and how do you use the different bands?
· How do you reduce annoying frequency areas?
· Where on the spectrum do the different instruments belong?
· How do you equalize a kick drum and a bass in relation to each other?
· How do you obtain a warm and brilliant vocal sound?

More technical questions include:

· What is asymmetrical, variable or constant Q?
· How do you use a dynamic equalizer?
· What are the pros and cons of phase linear/FIR EQ versus minimum phase/IIR EQ?
· What is the correlation between steep filtering, phase shift, and filter ringing?
· What is a Butterworth or Bessel filter?