The scales of Gambheera Nattai are as follows :
Arohanam (Ascending) : S G3 M1 P N3 S’
Avarohanam (Descending) : S’ N3 P M1 G3 S
It is a Janya raga, derived from Chalanatta (below), 36th in the Melakarta scale.
Gambheera Nattai is closely aligned to Nattai. One of the important functions of this raga is in the playing of Mallari, the processional music of temples played on the Nadaswaram. There is a good description and sample here. Well known kritis in this raga are Sri Vighna Rajam Bhaje by Oothukadu Venkata Subbaiyer and Sri Jalandharam by Jayachamara Wodayar,
Note : The 12 notes in the octave are named as below. Please note that C is used as Sa for the sake of simplicity as the scale is relative in Carnatic Music. Also note that the scales paint only a superficial picture of the raga as the gamakas(ornamentations) are a very important part of a raga.