Srila Prabhupada chanting Hare Krishna 64 rounds (1round - 7.30min)

The Hare Krishna mantra, also referred to reverentially as the Maha Mantra ("Great Mantra"), is a 16-word Vaishnava mantra and which from the 15th century rose to importance in the Bhakti movement following the teachings of Chaitanya Mahaprabhu. This mantra is composed of two sanskrit names of the Supreme Being - "Krishna" and "Rama."

Since the 1960s, the mantra has been made well known outside India by A. C. Bhaktivedanta Swami Prabhupada and his movement, International Society for Krishna Consciousness (commonly known as the "Hare Krishnas" or the Hare Krishna movement)
Hare Krishna - Mahamantra (16 rounds) (1round - 7.30min)
Prabhupada chanting japa in this version to nice music and birds songs, just remember try to chant carefully not like -
Hare Krishna Hare Krishna
Krishna Krishna Hare Hare
Hare Ram Hare Ram
Ram Ram Hare Hare

Japa must be full 16 words -
Hare Krishna Hare Krishna
Krishna Krishna Hare Hare
Hare Rama Hare Rama
Rama Rama Hare Hare
This is very, very important!