Musical instruments to be used during invocatory prayers are specified in the Pancharatra Agamas, said P.T. Seshadri in a discourse. Iswara Samhita says that jallari should be played for Vishnu; Kahala for Saraswathi, mardala for Chandra, tantri for Gandharvas, harsva mardala for Bhu Devi, pataha for Lakshmi, Kaamsya for Brahma. This is the rule to be followed during dwajarohana (hoisting of the flag) during Brahmotsava.
Paadma Samhita says that during pradosha and during abhisheka, musical instruments must be played. When the deity is being decorated (alankarasana), worship through dance, veena and flute is required. In his Nitya grantha, Ramanujacharya says that during alankarasana, chinha, kaahala and beri must be played, and dance must be performed. When Brahmotsavam begins, the beri is struck. Once the beri is sounded, no one should leave the town until the Brahmotsavam concludes.
Nine talas are mandated for beri — Ahvaana, pakshi, yushmat, mama, panchama, Indra, kumuda, Viswaksena and maatraadeena. During dwajarohana, khaga taala should be played on beri for Garuda, bali tala for Viswaksena, sama tala for Kumudan, malla tala for the five weapons of Vishnu, paddhava for Kumudakshan, malla tala for Vamana, mangala for Sankhukarna, jaya tala for Sarvanetra, Bhadra for Sumukha, and Adi for Agni. All devatas come to witness the Brahmotsavam. Paadma Samhita says sama tala is played in the East, paddhava in the South, malla in the South West etc. Manavala Mamunigal says that talas gajagarna, choragathi, Lakshmikirti, makharadwaja must be used for Thiruvaimozhi pasurams. Beri and dundubhi are mentioned in Vedanta Desika’s Yadavabhyudaya.
