Purvi lowers Re and Dha to komal and raises Ma to tivra: Sa komal-Re Ga tivra-Ma Pa komal-Dha Ni. It is Bhairav's scale with its Ma raised, and where Bhairav's raags belong to dawn, Purvi's belong to sunset: grave, glowing raags for the hour when day turns into night.
Its swaras
Purvi has the same narrow and wide steps as Bhairav, komal Re to Ga and komal Dha to Ni, but tivra Ma lifts its middle, so the scale seems both shadowed and lit. Many of its raags use shuddh Ma too, beside the tivra, and the two Mas side by side are part of the sunset sound.
All ten alankars in Purvi, to hear in your Sa →
How bright it is
Two komal swaras and one tivra: one step below Bilawal on the ladder, beside Khamaj.
On the circle of thaats
Purvi sits between Todi and Marwa: lower its Ga and it is Todi; raise its Dha and it is Marwa. And Bhairav stands beside it, outside the ring: bring Purvi's Ma back to shuddh and you have Bhairav.
Its raags
Purvi itself, Puriya Dhanashri and Shree are the great raags of sunset; Basant, of spring; Paraj, Gauri, Jaitashree and Rewa belong here too. Shree is one of the gravest raags there is, its leaps from komal Re to Pa slow and deliberate.
In the West and the South
There is no common Western mode with these swaras: it is a major scale with its second and sixth lowered and its fourth raised.
In Karnatic music it is the 51st melakarta, Kamavardhini, also called Pantuvarali.
Practise it
Practise the two narrow steps with care: komal Re above Sa, komal Dha above Pa, each held against the tanpura.
To make the ten thaats a daily riyaz, Meend has them ready: begin a riyaz of the thaats.
Questions
Which swaras are altered in Purvi thaat?
Re and Dha are komal; Ma is tivra. Ga and Ni are shuddh.
Which raags are in Purvi thaat?
Purvi, Puriya Dhanashri, Shree, Basant, Paraj, Gauri, Jaitashree and Rewa, among others.
How is Purvi different from Bhairav?
One swara: Purvi's Ma is tivra, Bhairav's shuddh. Purvi's raags belong to sunset, Bhairav's to dawn.