Alaap and Dhrupad in Chautaal in Raga Bhimpalasi.

Ustad Nasir Aminuddin Dagar & Ustad Zia Fariduddin Dagar
Raja Chatrapati Singh - Pakhawaj
Alaka Nandi - Tanpura

Words of the Dhrupad are here - https://dhrupad1234.files.wordpress.com/2013/03/bhimpalasi.jpg