Pertaining to those frequencies within that part of the audio range that is used for the transmission of speech.

The range frequencies normally considered necessary for the effective transmission of human speech. Typically 300 to 3,400 hertz.

An audio frequency in the range necessary for transmission of speech.

A telephone frequency adopted for the transmission of speech for commercial quality,i.e. 300 to 3000 hertz.

Any of the frequencies in the band 300-3, 400Hz which must be transmitted to reproduce the voice with a reasonable degree of clarity.

A voice frequency (VF) or voice band is one of the frequencies, within part of the audio range, that is used for the transmission of speech.