To provide a digital audio decoder which compensates a signal of a bass area to be cut by a speaker with a simple and inexpensive constitution.

A sub-band decoder 31 performs inverse quantization by sub- band samples. An equivalent higher harmonic calculation circuit 32 takes inverse quantization signals of a sub-band 0 of the lowest frequency and a sub-band 1 of the next lowest frequency as the input and detects signal levels of sub-bands 0 and 1 on the basis of these inputted signals. A signal level of higher harmonies is calculated on the basis of signal level of sub-bands 0 and 1. The calculated level is multiplied by a certain coefficient to obtain data for correction. A level correction circuit 3 adjusts levels of sub-bands 2 to 6 on the basis of data for correction outputted from the equivalent higher harmonic calculation circuit 32. A sub-band synthesizing filter bank 34 synthesizes outputs of the sub-band decoder 31 and the level correction circuit 33 to restore digital audio data (PCM data).