Matanga, the author of Brihaddesi, is the father of raga concept.
All music related works mention that Bramha derived music from Samaveda.
In the samagana scale, all 7 notes were used, but notes used to recite Rig Veda and Yajur Veda used fewer notes.
Archika gayanti means music revolved around one note,
Gathika gayanti means music revolved around two notes,
Samika gayanti means music revolved around three notes.
When reciting Rig veda, 3 notes were used i.e., Udatta, Anudatta, and Swarita representing r, n, s. Udatta and Anudatta were a note higher and a note lower respectively, while Swarita is related to both.
‘Udaattanudaatascha swaritascha swaraasrayaha|’
The scale of 3 notes gradually changed to the scale of 4 notes (Chatuswara).
Swarantara gayanti means music revolving around four notes.
Later panchamaswara, shatswara, and finally saptaswara singing has come into force.
Finally m-g-r-s-n-d-p are the sapta swaras, popularly known as ‘Shadja-Grama’