Classical music generation with recurrent neural networks
OK, just 'an idea'. Music is human impression. So one who want to train NN to impress humans with music, must first train NN to model human impression with all its limitations of perceived frequencies, reaction and tolerance to repeated patterns and so on. Then you may use the result as a limiting envelope for 'composing layer'. The good is that you will probably not need a human to estimate "humanness" of the result.