DIFFERENCE BETWEEN WIDE BAND AMR AND AMR

Traditional telefone systems transmit audio signals from 0,3kHz to 3,4kHz. This is also the audio bandwidth transmitted by standard AMR/FR and AMR/HR speech codecs.

However, the human voice also contains spectral components below and above that band. In simple words: spectral components below 0,3kHz make the transmitted human voice signal to appear warmer, and the spectral components above 3,4kHz more natural. The new AMR/wideband codecs are capable to transmit a much higher audio bandwidth. They represent one of the biggest improvements of voice quality in the history of telecommunications.