Pradyumna: People who have young children, perhaps they could take them away when the lecture is going on, so they don't make noise and disturb people from hearing.
Prabhupāda: So simply by vibration the atmosphere will be cleansed and purified. Just like when there is thundering sound in the sky, it does not require to understand by any particular language. That very vibration . . . and the origin of creation is sound. The grosser elements are visible, but the creation takes place from finer elements.
The sound is the symptom of the sky. By sound we can understand that there is sky, ether. Then, by sound vibration, there is circulation of air. And you have got practical experience, when there is very loud sound vibration, sometimes there is very strong wind also. So by sound vibration, the wind is started, and by strong wind, electricity is produced. From electricity, water is produced, perspiration. And from water, earth is produced.
So sound is the original element of creation. In Sanskrit language it is called śabda-brahma. Brahman, or the Absolute Truth, is . . . first appears . . . absolute Truth becomes knowable by sound. In the Bhagavad-gītā it is said—the Lord says—raso 'ham apsu kaunteya prabhāsmi śaśi-sūryayoḥ, śabdaḥ khe (BG 7.8). Śabda means sound.