History: What is the Doppler Effect?

What is the Doppler Effect?

• The technique of setting a sound in three-dimensional space.
  That is spatialization.
• The technique of shifting the amplitudes of a sound source between sound channels.
  That is panning.
• A sound moving towards us has a higher pitch, a sound moving away has a lower pitch.
  Excellent!
• The delay between ears which informs our sense of space of the sound.
  That is interaural time delay.