Dear Anil,
There are some devotees, who expressed that they had felt a void or a vacuum while meditating. Sri Bhagavan has elaborately discussed this void in one of His conversations. It is in Day by Day entry dated 21st July 1946:
Q: When I meditate I reach a stage where there is a vacuum or void. How should I proceed from there?
Sri Bhagavan: Never mind whether there are visions or sounds or anything else or whether there is a void. Are you present during all this or are you not? You must have been there even during void to be able to say that you experienced a void. To be fixed in that 'you' is the quest for the "I" from start to finish. In all books of Vedanta you will find this question of a void or of nothing [soonyam] being left behind raised by the disciple and answered by the guru. It is the mind that sets objects and has experiences and that finds a void when it ceases to see and experience, but that it not 'you'.
You are the constant illumination that lights up both the experiences and the void. It is like the theatre light that enables you to see the theatre, the actors and the play while the play is going on but also remains alight and enables you to say that there is no play on when it is all finished. Or there is another illustration. We see objects all around us, but in complete darkness we do not see them and we say, 'I see nothing'; even then
the eyes are there to say that they see nothing. In the same way, you are there even in the void you mention.
You are the witness of the three bodies, the gross, the subtle and the causal, and of the three states, waking, dream and deep sleep, and the three times, past, present and future, and also of the void. In the story of the tenth man, when each of the ten counted and thought there were only nine, each one forgetting to count himself, there is a stage, when they think one is missing and don't know who he is. And that corresponds to the void. We are so accustomed to the notion that all that we see around us is permanent and that we are this body that when all this ceases to exist, we imagine and fear that we have also ceased to exist.
Sri Bhagavan also quoted verses 212 and 213 from Vivekachoodamani, in which the disciple says: "After I eliminate the five sheaths as not-Self, I find that nothing at all remains." And the Guru replied that the Self or That by which all modifications [including the ego and its creatures] and their absence that is void, are perceived is always there.
Then, Sri Bhagavan continued speaking on the subject and said: "The nature of the Self or "I" must be illumination. You perceive all modifications and their absence. How? To say that you get illumination from another, would raise the question how he got it and there would be no end to the chain of reasoning [reductio at infinitum].
So you yourself are the illumination. The usual illustration of this is the following: You make all kinds of sweets of various ingredients and in various shapes and they all taste sweet because there is sugar in all of them and sweetness is the nature of sugar. And in the same way, all experiences or the absence of them contain illumination which is the nature of the Self. Without the Self they cannot be experienced, just as without sugar not one of the articles yo make can taste sweet.
A little later, Sri Bhagavan said also said: First one sees the Self as objects. Then one sees the Self as void. Then one sees the Self as Self, only in the last there is no seeing, because seeing is Being.
Arunachala Siva.