I didn’t think it sounded like Morse code, so I Googled for ways to encode a message in music, a technique known as stenography . I found a Lifehacker article talking about the Dark Knight apparently using this technique, which led me to the program Sonic Visualizer. I was stumped at first, because their only instruction was to “Add spectrogram and play with it. However, I had to add a specific type of spectrogram, the “melodic range spectrogram”. A little tinkering with the zoom on the waveform produced the image:
This is brilliant decoding work, and hope that we will have him for more sound puzzles! Hats down!