It is hard to hear sounds from digital TV or mobile phone in noisy environment because of masking effect. It could be solved by a simple amplification; however, special process for masking bands will be a further solution in some restricted situation. We proposed an algorithm named 'perceptual irrelevant component elimination' using a modified multi-band dynamic range compressor, which does not increase the signal level and enhances its perceptual signal-to-noise ratio by about 1 dB for speech signals and about 3 dB for music signals.