Voice quality
As voice quality , the quality is of course understood a human voice during playback by technical equipment.
A noise- and distortion-free reproduction of the spoken word is generally rated as “good” speech quality . The voice is pure and understandable.
An assessment of the voice quality is subjective and depends on the given technical means, the environment of the recording , the transmission path and the environment of the playback .
Telephony
Thanks to the good error correction and the available bandwidth , ISDN calls are noise-free and usually crystal clear.
In telephony, the Mean Opinion Score was introduced to evaluate language .