In Sanskrit there are thirteen vowels and thirty-five consonants. The vowels are a, ā, i, ī, u, ū, ṛ, ṝ, ḷ, e, ai, o, au, and the consonants are ka, kha, ga, gha, etc. Amongst the consonants, the first twenty-five letters are called the sparśas. There are also four antaḥ-sthas. Of the ūṣmas there are three s’s, called tālavya, mūrdhanya and dantya. The musical notes are ṣa, ṛ, gā, ma, dha, and ni. All these sound vibrations are originally called śabda-brahma, or spiritual sound. It is said, therefore, that Brahmā was created in the Mahā-kalpa as the incarnation of spiritual sound. The Vedas are spiritual sound, and therefore there is no need of material interpretation for the sound vibration of the Vedic literature. The Vedas should be vibrated as they are, although they are symbolically represented with letters which are known to us materially. In the ultimate issue there is nothing material because everything has its origin in the spiritual world. The material manifestation is therefore called illusion in the proper sense of the term. For those who are realized souls there is nothing but spirit.