I didn’t see this described, but OM is considered the 1st sound of generation in yoga tradition, suitable? Would make me would like to chant OM even though looking at my Yantra! Mantras, which are Sanskrit syllables inscribed on yantras, are necessary "assumed types" that characterize divinities or cosmic powers https://directory-daddy.com/listings13493996/the-basic-principles-of-beej-mantra