Jaathi:
Jaathi refers to the number of matras (counts) in the laghu component of a tala. It directly affects the total length of a tala cycle.
Types of Jaathi:
Tisra Jaathi – 3 counts
Chaturasra Jaathi – 4 counts
Khanda Jaathi – 5 counts
Misra Jaathi – 7 counts
Sankeerna Jaathi – 9 counts
Gathi (Nadai):
Gathi, also called Nadai, refers to the subdivision of each beat in a tala. It determines the flow and speed of rhythm within each beat.
Types of Gathi:
Tisra Gathi – 3 subdivisions per beat
Chaturasra Gathi – 4 subdivisions (most common)
Khanda Gathi – 5 subdivisions
Misra Gathi – 7 subdivisions
Sankeerna Gathi – 9 subdivisions
Difference:
Jaathi modifies the laghu length.
Gathi changes the internal spacing of beats.