Music models for music-speech separation

We consider the task of speech recognition with loud music background interference. We use model-based music-speech separation and train GMM models for music on the audio prior to speech. We show over 8% relative improvement in WER at 10 dB SNR for a real world Voice Search ASR system. We investigate the relationship between ASR accuracy and the amount of music background used as prologue and the the size of music models. Our study shows that performance peaks when using a music prologue of around 6 seconds to train the music model. We hypothesize that this is due to the dynamic nature of music and the structure of popular music. Adding more history beyond a certain point does not improve results. Additionally, we show moderately sized 8-component music GMM models suffice to model this amount of music prologue.