Valmiki Ramayana Yuddha Kanda Sarga 58 Shloka 25

तदा then, आवर्ते revolving, क्षुभितस्य agitated, अप्रमेयस्य boundless, सागरस्यइव like an ocean, उभयोः both, सेनयोः armies, निःस्वनः sound, सञ्जज्ञे was frightening.

Then the sound of both armies was like an agitated, boundless ocean, whirling round and frightening.