| 摘要 |
PROBLEM TO BE SOLVED: To provide an audio unit that provides a flat output sound signal for a low frequency band even when a light load is connected to the audio unit. SOLUTION: A low frequency signal extract circuit extracts a low frequency signal at a low frequency band of a power amplifier for right and left channels, when a usual load is connected to output terminals of the power amplifier, the low frequency correction circuit amplifies the low frequency signal extracted by the low frequency signal extract circuit and feeds back its output to the power amplifier, and when a light load such as an external speaker with a low resistance is connected to the output terminal of the power amplifier, the low frequency correction circuit is deactivated to act on a buffer circuit. |
