Each chakra has a standard sound. By meditating on these sounds and focusing on the specific chakra, this is one way of opening up your astral hearing.

• Base Chakra, the physical Level:
  Sounds include thunder or a soft hissing. Red
  
  
• Sacral Chakra, the astral Level:
  Roar like the ocean or the sound of wind. Orange
  
  
• Third chakra the level of will:
  H-h-h-a-a-h-h-h sound (silent, like an exhale- no voice; long and continuous) or the sound of humming/vibration “aum.” Yellow
  
  
• Heart Chakra, the intuitional Level:
  Buzzing like a bee (bioelectricity) or the sound of a flute. Green
  
  
• Throat Chakra the mental Level:
  Azazel gave me a sound. The best way I can describe it is like twisting a balloon. Humming can also be used. Blue
  
  
• 6th Chakra, the soul Level
  The sound of woodwind instruments. Bluish violet (indigo)
  
  
• Crown Chakra, the blissful Level
  Whisper or no sound- this is felt rather than heard. Violet