This silence underlies the oma. This silence is apart. The expresses deep sleep and the deep sleeper. And the silence after that expresses the one reality. When all the three have ceased, the or has merged into the o,. Has merged into the m, and the m m merges into the silence. All three are there, that's the trick. That fourth the pure consciousness, the atman, the turia, is right here. Only it has put on the dress of the waker.
Swami Sarvapriyananda teaches one of the shortest and most profound upanishads accompanied by Gaudapada's Karika. This lecture covers Mantra 1.