Not sure what to make of this app. It turned up a few days ago and I’ve been meaning to post something on it since. The description sounds very interesting. Anyone tried it out?
MUSYS is a music understanding system developed for Apple iPad/iPhone/iPod Touch platforms. Use MUSYS to tune your instrument, transcribe music, figure out a song, as an improvisation tool, learn music theory, or do harmonic mixes. See music while you listen to it – from the sound spectrum, to notes on a musical staff, to scales, chords, and key changes in the circle of fifths.
MUSYS “understands” the theory of Western music in terms of notes, scales, chords, and keys. It starts by detecting musical pitches in an audio signal. After correcting for overtones (since sometimes the harmonics of musical instruments are louder than the fundamental pitch), and removing correlated background sounds (e.g., from percussion instruments), pitches are converted into notes that are displayed on a standard musical staff. Next, MUSYS uses model-based techniques to fit musical scales to melodies and chords to harmonies. 2-D maps show the chords and scales that best match the music being played. Finally, MUSYS uses the match scores of scales as “votes” for the current musical key in the circle of fifths.