sa vikraman putra-vadhepsur ojasa
nisamya nirhradam apurvam adbhutam
antah-sabhayam na dadarsa tat-padam
vitatrasur yena surari-yutha-pah
sah—he (Hiranyakasipu); vikraman—exhibiting his prowess; putra-vadha-ipsuh—desirous of killing his own son; ojasa—with great strength; nisamya—hearing; nirhradam—the fierce sound; apurvam—never heard before; adbhutam—very wonderful; antah-sabhayam—within the jurisdiction of the great assembly; na—not; dadarsa—saw; tat-padam—the source of that tumultuous sound; vitatrasuh—became afraid; yena—by which sound; sura-ari-yutha-pah—the other leaders of the demons (not only Hiranyakasipu).
While showing his extraordinary prowess, Hiranyakasipu, who desired to kill his own son, heard that wonderful, tumultuous sound, which had never before been heard. Upon hearing the sound, the other leaders of the demons were afraid. None of them could find the origin of that sound in the assembly.
“O son of Kunti [Arjuna], I am the taste of water, the light of the sun and the moon, the syllable om in the Vedic mantras; I am the sound in ether and ability in man.” Here the Lord exhibited His presence everywhere by the tumultuous sound in the sky (sabdah khe). The tumultuous thundering sound was proof of the Lord’s presence. The demons like Hiranyakasipu could now realize the supreme ruling power of the Lord, and thus Hiranyakasipu became afraid. However powerful a man may be, he always fears the sound of a thunderbolt. Similarly, Hiranyakasipu and all the demons who were his associates were extremely afraid because of the presence of the Supreme Lord in the form of sound, although they could not trace out the source of the sound.
Link to this page: https://prabhupadabooks.com/sb/7/8/16