Udgitha forms the second part of Sama Veda and relates to the chanting of the songs. Meditations are helpful for the non-dualistic realization of the Supreme Brahman. They purify the mind of the seeker, present a glimpse of Brahman and can be practiced easily. Hence these are included at the beginning of Upanishads. For a normal individual, practice of Vedic rites is deep rooted and it will be very difficult to practice meditation entirely giving up the rites. Hence meditations associated with the rites are presented. Meditation on omkara through Udgitha is one such meditation given. As one starts singing Udgitha by uttering om, om is itself called Udgitha.
Himkara, Udgitha, Prastava, Pratihara and Nidhana are the divisions of the Sama Veda. Udgitha is a way of singing samans. Sama is sung over the base Rik mantra. Different portions of Rik mantras are sung in different bhaktis and Udgitha is considered to be an important bhakti. It is the essence of all essences and regarded as eighth in the series of essences.
Udgitha is eulogized as Angirasa, Brihaspati, etc., as vital force is the deity of Udgitha. Thus Udgitha is considered as one of the important meditations attached to a rite which will lead to the fulfillment of various desires. It also purifies the mind, leading to liberation through knowledge of the Absolute.
The organ of speech is the essence of the human body. Of Speech, Rk is the essence; of the Rks, the sama mantra are the essence; and of the sama mantras, Udgitha is the essence. Thus we find Udgitha is the eighth essence in the series. Now vak is Rk, sama is prana and Udgitha is to be meditated as Udgitha. Having known this, one meditating on Udgitha as the letter om becomes verily the fulfiller of all desires.
As a eulogy on the Udgitha meditation, a story is stated in Chandogya Upanishad. Gods – the good thoughts as given in knowledge texts; and demons – as the worldly thoughts engrossed in the sensual pleasures, fought against each other. Gods wanted to defeat the demons with the help of Udgitha. They requested the vital force in the nose to sing Udgitha for their sake. But it had the weakness of having been puffed up with pride, that is smelt sweet odor only. The demons had afflicted it with vice and henceforth it started smelling both the fragrant and fetid. Similarly, the demons afflicted with vice the organs of speech, of vision, of hearing, of thinking etc., when they started singing Udgitha at the instance of the gods. Finally, only the vital force could sing Udgitha successfully, as it had no weakness, and the vice thrown by the demons was destroyed as clay destroyed when hit on an impenetrable stone.