This invention describes a mobile phone with a means of measuring a
background sound level of an environment. When a user either initiates or
receives a phone call, sound levels before and during the call are
compared. Once it is decided that the voice is too loud based on a
predetermined criteria, the phone gives the user a feedback indicating
that the voice is too loud and potentially a disruption to other people.
Furthermore, the present invention provides a feedback for a voice
adjustment by utilizing a sidetone adaptive signal that filters the user
own speech directly to an earpiece.