Voice-band is the frequency band, or range, specified for voice communications in the public switched telephone network (PSTN). whether the range of audible sound is 20-200,000 Hz the voice band has a specific value which is 300-3300 Hz

Source:

T101 Telecom 101 – 4th edition 2016
7″ x 9″ softcover book • 488 pages • 4th edition • published 2016
ISBN 9781894887038 (print)   ISBN 9781894887786 (eBook)