In the past months a number of mobile network operators in Europe have switched-on Wideband-AMR in their 3G networks which offers superior sound quality between two WB-AMR mobiles. On paper the difference is tremendous with the frequency range of around 3 kHz extended to 7 kHz, thus transmitting voice and music much clearer than we know today. But how does one perceive the difference in practice?
A hard environment to test this is for example in a train with background noise and recently I had a WB-AMR call while being just in such a place. In short, the experience was incredible for both parties. While on the train I had no difficulties at all to understand the other end and the voice was crystal clear. The positive impression was reinforced when the call dropped due to a coverage hole and when subsequently re-established in the GSM non WB-AMR network I had to make an effort to understand the other side and crank up the volume. I always thought narrow band AMR was quite o.k. but once you've heard wideband it suddenly doesn't sound so good anymore until after a while you ear adapts to it again.