Types of effects

• Spectral effects
• Dynamic range effects
• Time delay effects and Reverb
• Others
  

Spectral Effects

• Filters
• Effects in the frequency domain
• Non-linear effects (e.g. distortion)
• Phase vocoder

Filters

• Filters change the spectrum of a sound
• They don't (in theory) add anything, they just adjust what is already there.
• Uses:
• Adjust "color"
• Fix small problems
• Extreme effects
• Improve interaction with other elements in a mix
  

Audio Filters

Low cut/High pass

High cut/Low pass

• Cutoff
• Slope
  

Parametric EQ

• Center freq, Bandwidth/Q, Gain

Cross-over filters

Graphic Equalizer

Shelf filters

Resonant filters

Additional resonance parameter

Non-linear effects

Distortion

Spectral processing

(in the frequency domain)

Phase Vocoder

Dynamic range processing

Compression/Expansion

Noise gate

Only level is changed, but it is changed dynamically according to the signal's (or sometimes another's) own level

Compression

Compression

Compressor knee

Uses of compression

• Reduce dynamic range
• Avoid spurious peaks
• Reduce transients
• Emphasize transients
• Homogenize level
  

Expansion/Gating