The final sound of the OM chant and invocation is "M". You can practice this sound by writing out three Ms side by side ...mmm. Slowly say "m" over two seconds...and so for five or six seconds you resonate an unbroken M sound. This sound represents purity of mind in Tibetan Buddhism and the dissolution of temporary form in Hinduism. The M sound is the spiritual bridge between the mind and the realm of Divine Spirit. Om. Amen.