class AudioDataProcessor {

    Result ProcessManyFiles {
        for(/*many files*/) {
            //...
            //...
            readAudioFile();
            //...
        }
    }

    //only one channel wave file
    AudioData readAudioFile(File file) {
    //... reads one file
    }
}

class MainApp {
    public static void main() {
        //...
        //...
        audioDataProcessor.processManyFiles();
        //...
    }
}