| 摘要 |
PURPOSE: A volume control device of a car audio is provided to decide size of a noise generated according to an increase of a running speed of a car, and to automatically turn up the volume of a sound. CONSTITUTION: A signal processor(70) processes an analog signal generated from a sound source(60) according to a volume set by a user. An amplifier(80) amplifies a digital signal converted from the signal processor(70). An output unit(90) outputs a sound of a volume in accordance with the amplified digital signal. A microcomputer(100) compares a size of the amplified digital signal with a size of a noise generated from a car, and maintains a difference between the compared sizes at certain interval.
|
