Vibrate in tune with the universe.
Almost everything in the universe vibrates at a frequency of 432 Hz the same you produces by uttering A-U-M.
The symbolic and practical unification with the universe aids the spiritual process tremendously.
Easy to do
The biggest obstacle to overcome in chanting mantras is the cringe you might feel by possibly being watched. At least it was for me. The advantages to feel the vibration of your own voice and the conscious states you reach by that are worth it. You will find simple instructions on mantras on p.49 of the Ebook.
Trust a culture like the yogic on sound
The yogic tradition managed to convey vast amounts of knowledge orally over millenia.
If you like to find out how to use mantras to intensify the spiritual experience go ahead and check out my ebook SPIRITUAL PUNK