Sandhikaal, the twilight period between day and night is called Sandhiprakash. Such a period occurs twice - once before sunrise (dawn) and the second before sunset. The ragas sung /played during these periods are called Sandhiprakash ragas. In these ragas, the Gandhar is shudha (natural) and Dhaivat is komal (flat). In the Sandhiprakash ragas sung at dawn, often, the Gandhar is shudha, Rishabh and Dhaivat are komal and Madhyam is shudha. This raga is sung/played between 4a.m. to 7a.m. Eg .Kalingada, Ramkali, Jogiya ,Bhairav etc of Bhairav Thaat. In the ones sung or played in the evening hours the Gandhar is shudha, Rishabh-Dhaivat komal, but their Madhyam is teevra. eg Purvi, Puriyadhanashri, Marva, Puriya etc.
Characteristic Features of Sandhiprakash ragas:
- Ragas sung/played in the twilight period are known as Sandhiprakash ragas.
- In their format, the Gandhar must necessarily be shudha and Rishabh Dhaivat komal.
- Conventionally, in Sandhiprakaash ragas sung/played at dawn, the Madhyam should be shudha and those sung/played in the evening, Madhyam should be teevra.
- In Sandhiprakaash ragas, Rishabh is never varjit.
- In a 24 hour period, Sandhiprakaash ragas are sung / played twice – a)Pratahkaleen Sandhiprakash ragas (sung at dawn) b) Sanyankaleen Sandhiprakash ragas (sung at sunset)