数字音频信号滤波：读取音频文件，加入噪声，设计合理的带阻滤波器，滤除噪音，并给出所有音频的频谱以及播放试听所有声音。-Digital audio signal filtering: read audio files, add noise, the rational design of band-stop filter to filter out noise, and given all the audio spectrum and play to listen to all voices.