A person recently asked me what I meant by the term business system.. I thought others might like to know a definition that works for me. A system is a procedure, process, method, or course of action designed to achieve a specific result.
The voiced speech of a typical adult male will have a fundamental frequency from 85 to 180 Hz, and that of a typical adult female from 165 to 255 Hz. Thus, the fundamental frequency of most speech falls below the bottom of the voice frequency band as defined above.
Humans can hear sounds approximately within the frequencies of 20 Hz and 20,000 Hz. Anything below 20 Hz, typically cannot be heard although it can be felt. This can be experienced to when you feel the bass of a song. Likewise humans normally cannot hear any sounds above the frequency of 20,000 Hz.