A digitial voice signal with a greater range of frequencies. Also branded as "HD Voice" by Polycom, the narrowband 300-3400 Hz frequency range of the traditional "toll quality" telephone call was broadened to 50-7000 Hz for wideband audio.
Desk phones, smartphones and tablets increasingly support wideband audio to enhance the audio in a voice over IP (VoIP) phone call or the audio in a video call. Ordinary microphones and the analog-to-digital converters (ADC) in a computer's sound card are not limited to narrowband frequencies. This is why a voice over IP (VoIP) phone call from PC to PC often provides superior voice clarity than a traditional landline call and especially a regular cellphone call. See G.722
First in Europe
Starting in 2009, cellular carriers in Europe and around the world added support for wideband voice, while U.S. carriers delayed deployment until 2013.