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Miss H, great you revived this informative thread!
... a subtle background sound we sense if we tune in, otherwise silent but ever present and which we can hear if we choose to even in the midst of loud external noise or music. Tinnitus on the other hand probably varies over time and has to do with Zinc / B12 deficiency ... the key thing being that it’s disturbing whereas the background astral sound is not.
In deep meditation ... at the vibrant void level in stillness the primal sound AUM in as a deep reverberation is heard. Whether we say it as Aum or Om or Home or Naam or on the same lines possibly has to do with our cognition through enabled sentience.
Kind of like the sound of the Sun
https://youtu.be/FcZqGQ8Ra5U
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