Ducking
Best Practices for Audio Mixing
Mixing Techniques for Memorable Soundtracks
Mixing Techniques for Film Soundtracks
Mixing Techniques for Contemporary Music
Mixing Techniques Improvement
Best Practices for Audio Mixing 
Sidechain Compression: Create space in the mix by
ducking certain elements, like the bass under the kick drum
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Mixing Techniques for Memorable Soundtracks 
Use sidechain compression to create breathing space between elements, such as
ducking the bass when the kick drum hits
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Mixing Techniques for Film Soundtracks 
ducking music under dialogue)
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Mixing Techniques for Contemporary Music 
Sidechain Compression: Creating a pumping effect by
ducking one signal when another is present
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Mixing Techniques Improvement 
Frequency
Ducking: A method of reducing the volume of one track when another track plays to maintain clarity
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Nebenberuflich selbstständig 
Nebenberuflich selbständig ist, wer sich neben seinem Hauptjob im Anstellungsverhältnis eine selbständige Nebentigkeit begründet.