Sanskrit
ततः शङ्खाश्च भेर्यश्च पणवानकगोमुखाः । सहसैवाभ्यहन्यन्त स शब्दस्तुमुलोऽभवत् ॥
tataḥ śaṅkhāś ca bheryaś ca paṇavānakagomukhāḥ sahasaivābhyahanyanta sa śabdas tumulo'bhavat
Translation
Then conches and kettledrums, tabors and drums and cowhorns, suddenly blared forth, and the sound was tumultuous.
Annie Besant · The Bhagavad-Gita, translated by Annie Besant (4th ed., 1922) — Wikisource · Public Domain
Explanation
Bhîshma’s single conch triggers a full instrumental response across the Kaurava army — conches, kettledrums, tabors, drums, cowhorns, all at once. It’s the formal, ceremonial opening of the battle, sound before a single blow is struck.