A precondition of meditational practice is a build-up of defensive armour to protect the practitioner from the onslaught of evil influence of external environment. The process of the build-up is repeated loud recitation of the syllable "arham". Synchronised with the recitation, there should be a mental projection of the step-by-step build-up of the protective shell. The shell is being woven from the crisscross of the electromagnetic radiations, emanating from the sound waves thus produced. The radiations ultimately merge together and build an impregnable armour-like cover enveloping the practitioner keeping him safe for the duration of the practice.
Recitation of Mahaprana Dhvani(Prolonged Exhalation with Sound)
As an alternate to the recitation of arham, mahaprana dhvani is practised as a precondition of meditation. In this, the mouth is closed and the tongue is kept touching the palate. The humming sound of bee is produced through nostrils during the prolonged exhalation. As before, a defensive armour is built up by the repetition of the sound.