PURPOSE: To improve compressibility and to perform bit distribution among channels by detecting energy for each channel and performing encoding in which information quantity of each channel is allocated with a ratio in accordance with this detected output.

CONSTITUTION: This device has compression-encoding circuits 2021-202n and entropy encoding circuit 2031-203n being a first encoding means in which digital audio signals of each channel CH1-CHn are inputted and the digital audio signals are compression-encoded. This device has also a second encoding means in which an output encoded signal of the first encoding means is supplied, energy for each channel is detected, and encoding is performed in which information quantity of each channel is allocated. This second encoding means has a Log spectrum envelop detecting circuit 208, a distribution deciding circuit 209, an adaptive quantization circuits 2031-203n, and a sub-information compression circuit 2041-204n. Thereby, bit distribution among channels and high compressibility can be realized.