Now, the whole material world is produced from sound. That is scientific fact. Scientists are researching the importance of sound, physical science. Sound, light, and transmission of sound and light. There are so many things, electronics. So this sound vibration, this is material sound. They have got so much wonderful power. And just try to understand what is the power of the spiritual sound. Real sound is coming from the spiritual world. It is simply just like gramophone. The sound is coming originally from the person; the gramophone is reproducing. That is not the original source of the sound.
Similarly, whatever sound is there in this material world, the original sound is produced by God. Just like in your Bible it is said, "Let there be creation." It is, simply it was sound and there was creation. So spiritual sound is so powerful. And we are trying to catch you directly from that sound vibration, Hare Kṛṣṇa, and I am sure it is acting. Simply, śabdād anāvṛttiḥ.
Prabhupada's lecture - Śrīmad-Bhāgavatam 1.5.2 - Los Angeles, January 10, 1968