For intelligible speech transmission, which frequency range needs to be transmitted?

To ensure intelligible speech transmission, the frequency range that is primarily transmitted is from 300Hz to 3kHz. This range encompasses the essential frequencies used in human speech, where the most critical phonetic information resides. The components that convey the clarity of consonants and the richness of vowel sounds typically fall within this bandwidth, making it vital for effective communication.

Frequencies below 300Hz are more associated with low-frequency sounds that do not contribute significantly to speech intelligibility, while frequencies above 3kHz contain higher harmonics that can enhance clarity but are not necessary for basic understanding. Thus, the selection of 300Hz to 3kHz aligns with the requirements for clear and effective speech transmission, confirming its correctness as the range indicated for intelligibility.