Sound waves can potentially affect a human's consciousness, but it is highly unlikely that they can directly "knock out" a person into an unconscious state like in movies or video games. While sound can impact our bodies and senses, it typically requires extremely intense or specific conditions to cause unconsciousness.
There are certain frequencies, known as infrasound, that are below the threshold of human hearing but can still be felt by the body. In some cases, exposure to very intense infrasound can cause feelings of unease, dizziness, or even nausea. However, the effects vary from person to person, and the likelihood of losing consciousness solely from infrasound is quite low.
On the other hand, extremely loud sounds in the audible range can damage the ears and potentially lead to a loss of consciousness. These high-intensity sounds can cause physical harm, such as rupturing eardrums or damaging the delicate structures of the inner ear. However, losing consciousness in this scenario would be a secondary effect resulting from the physical trauma rather than a direct result of the sound wave itself.
In summary, while sound waves can have various effects on the human body, including causing discomfort or physical harm, directly knocking someone unconscious through sound waves alone is highly improbable.