A quick recap on the five states of sound or vibrations.
The first is absolute stillness, there is no vibration at all.
The second, there is vibration but we are not able to hear it due to the absence of certain factors such as a medium for its transmission.
This is called para-shabda.
An example is the sound produced by a rock falling on the surface of a planet a million light-years away from us.
The event happened, but the sound did not reach the earth.
Then there are three levels of apara-shabda.
The first is sound that can be heard by an absolute-ear.
An ear that can sense even the tiniest and the largest vibration.
In the second level of apara-shabda are vibrations that can be sensed by ears or instruments that are much more sensitive than the ordinary human ear.
The ordinary human ear can hear only between 20 Hz and 20 kHz.
Yogis can hear much beyond this range.
Machines can catch much beyond this range.
Then the ordinary sound which we hear which is the third level of aprara-shabda.
Creator Brahma, Prajapati Brahma has got an absolute ear, what he heard at the time of creation is para-shabda.
This para-shabda is the intrinsic pattern of vibration which is set to chhandas such as gayatri, ushnik, anushtup.
These vibrations are what he heard.
And when he reproduced them, the objects and beings corresponding to them were created.
This is the process of creation.
Only Prajapati Brahma has the absolute-ear.
Even his own manasa-putras don't have an absolute-ear.
Their hearing is a bit inferior to that of Brahma.
They can hear apara-shabda of the highest level and when they reproduce them, objects and beings are created.
But these are not the exact vibrations of the objects and beings and forces and thoughts.
They are equivalents; near-equivalents.
The collection of such sounds and vibrations is the Veda; that is why Veda has the power to manifest.
Veda when pronounced can manifest objects, effects, and forces.
But if you pay attention to this whole sequence, you will see that Prajapati, rishis, us they are all various levels of awareness.
I as a human being, my awareness is limited to a few people, a few colors, a few objects, a few sounds.
If I elevate my awareness to the level of a yogi and sharpen my hearing I can hear the sound of the buzzing of a bee 100 km away, provided I focus on that, I want to hear it.
I can overhear the conversation between A and B sitting 1000 km away from me.
Or even what they are going to talk about after 10 years.
At the level of the creator-rishis, the Prajapatis such Kashyapa, Daksha, each one is delegated a certain task in creation.
Like Kashyapa is the creator of devas, daityas, danavas.
At his level of awareness, he can hear the vibrations of all of them and by reproducing them he can manifest them.
Here also it can be pure creation or procreation.
At the topmost level is Prajapati Brahma, the creator Brahma, the father of all these creators.
That's why is called pitamaha, the grandfather.
At his level of awareness are the vibrations of everything in the whole universe.
So, basically, these are just different levels of awareness of the intrinsic vibrations of objects and beings.
Starting with the lowest at my end as a human being and the highest and complete at the level of Prajapati.
I can through practice elevate my awareness.
What I see is a tiny part of the universe as of now.
As I raise my level of awareness I can see much more.
This is explained in a beautiful way in the Puranas.
Sri Hari's abode, Vaikuntha or Goloka...
Goloka is easier to understand because the term also means the world of the sounds, the world of vibrations.
From there, when Sri Hari wanted to create the universe, Ganga originates from his feet.
This Ganga is para-vak, the para-vibrations.
Then Brahma caught Ganga in his kamanadalu.
He captured the entire para-shabda-brahma.
And then released it to lord shiva's jata.
Shiva being yogeesha, the highest yogi, got it as the highest level of apara.
The difference between this and Brahma's para-shabda is just a hairline, almost the same.
From Shiva's jata, Ganga descended into the world through Gangotri which is the real-world experience of objects and beings and forces and actions.
Basically, it is all about vibrations of certain patterns and your capacity to sense them.