It is often believed that incanting this mantra out loud or silently will invoke the blessings of Chenrezig, the embodiment of compassion.
There are six syllables to the mantra -
Om - Ma - Ni - Pad - Me - Hum. The mantra originated from India and emigrated north. In Tibet the pronounciation can be slightly different to the Indian way. Instead of Om Mane Padme hum, it is pronounced Om Mane Peme Hum.
The way that it is pronounced may seem important to purists, however it is, as always, the intention behind the recitation that delivers the goods!
A little story to illustrate this -
A brief quote from Dilgo Khyentse Rinpoche
from his ' Heart Treasure of the Enlightened Ones'
" There is not a single aspect of the eighty-four thousand sections of the Buddha's teachings which is not contained in Avalokiteshvara's six syllable mantra "Om Mani Padme Hum", and as such the qualities of the "mani" are praised again and again in the Sutras and Tantras.... Whether happy or sad, if we take the "mani" as our refuge, Chenrezig will never forsake us, spontaneous devotion will arise in our minds and the Great Vehicle will effortlessly be realized."
Now listen to the rendition that Hein Braat presents and the pronounciation can be easily picked up.
The mantra Om Mane Padme Hum continues for approx 27 minutes.
The Om mantra for approximately the same time