I want to know that while practicing to listen the sound of Aum what does it means to become one with the sound we hear. How can we become one with the sound.
AUM is much more than just a sound that we can hear in meditation. It is the creative force of the whole universe. AUM is the vibratory aspect of God.
When we "listen" for the sound of AUM, we are trying to attune ourselves with that vibration.
As human beings, we are vibrating at a human level. When we strive, in meditation, to attune ourselves to the higher vibration of God, then with God’s help and our own efforts, we, too, take on a higher, God-like vibration.
This is done by tuning in to the vibration of our God-nature (the Higher Self) which has always been there, but which has been covered over by delusion (maya).
We are, already, one with the sound of AUM, for it is what made us and remains forever a part of us. It the essence of our beings. The problem is that we have forgotten this and now need to realize it again, with every fiber of our being.
The great masters say that by communing with AUM, you remember who you really are. That is what is meant by "becoming one with the sound of AUM."
It is like re-tuning a radio which has been long-neglected and has "drifted" off the station of AUM.