In the 10th Khaṇḍa of Paraśurāma Kalpasūtra we can find the well-known 37 Raśmi Mālā Mantras, which are broken into the 6 sets. Below is a brief commentary by Guruji on these mantras.
Seventy million mantras are said to have emanated from the five faces (plus two) of Shiva. Obviously, it would be difficult to recite or perform sadhana using all of these mantras. So the sages grouped them into several categories, each corresponding to one of the seven chakras—and yes, there are people who practice them all! But the Paraśurāma Kalpasūtra does not refer to them all. It simply picks up a few mantras from each chakra, and collectively calls them the Raśmi Mālā mantras. In the tradition of Paraśurāma, the recitation of these mantras is enough.
Every Śrī Vidyā upāsaka who has received Pañcadaśi or higher mantras is supposed to recite the entire set of Raśmi Mālā mantras first thing in the morning. The recitation should be done internally, with each mantra recited only once. That’s all that is required.
Raśmi - means a ray; Mālā - means a garland - a garland of rays to the Mother Goddess. These are mantras relating to the Goddess and Her powers to heal us in so many different ways. Each of these mantras resonates sympathetically with the vibration of the chakra being meditated upon, thus enhancing its powers.
Guruji Amritananda