Ever get confused about how to chant OM? I know I have. So, I decided to do some research. I mean, I didn’t want to go about chanting the sacred syllable in vain. I wanted to get it right. So, I decided to find out just how to chant OM the right way, while also understanding a little about the science behind it in the process.
(Related question: What is a japa mantra?)
Turns out, chanting OM is both an art and a science — just like the yoga tradition itself. In fact, the Upanishads, one of the most beloved and sacred of ancient yogic texts, explain the science behind OM. The Upanishads teach us that the sound of OM is made up of three different sounds. We can see these three sounds when we spell it AUM instead. The first sound is the A, which sounds like "ahhhh." Then there’s the U sound, which sounds like "ooohh." And last, the M sound, or "mmmmm."
When you chant OM, or AUM, you chant each sound in order to make the full sound complete. It’s believed that each sound — the ahhhh, the ooohh and the mmmmm — activate different degrees of consciousness. Therefore, it’s necessary to give each sound ample attention. The ahhhh sound is connected to material consciousness. In other words, it corresponds to your material body and its place in your physical environment. The ooohh sound corresponds to the more subtle energy of your mind, while the mmmmm sound speaks to consciousness beyond the mind, to the more causal realm.
(Related question: What is "beginner's mind?")
As you chant A-U-M, emphasize the ooohh and the mmmmm sound more than the ahhhh. In other words, hold those sounds longer than the ahhhh. We do this because, in yoga, we’re trying to move our awareness away from the material, base levels of consciousness, to the more subtle forms of conscious awareness. Feel those sounds come together at the crown of your head, linking you to the highest form of truth and reality.