I have been reading a couple of really interesting books, as of late, about music and how it works; perfect reading for a nerd engineering type. One of the more interesting aspects of the read is the mechanism our ear/brains use to recognize what instrument is playing the notes in music.
We all recognize that two different instruments playing the same note sound very different indeed: perhaps an oboe and a violin as an example. Not one of you would have any trouble telling the difference between the two instruments on even the cheesiest of stereo systems; certainly those differences are quite apparent on my ear buds playing MP3 in the gym.
And if I had to guess what differences in sound distinguished the two instruments from each other it would be obvious to me - the harmonic content of the instrument - and I would be wrong.
We know that both the oboe and the violin are playing the identical note, called the fundamental, and their sonic signature differences can easily be seen on an oscilloscope; so different their harmonic content. But surprisingly enough while the scope can easily see those harmonic differences it's not the same for our ear brains.
What, pray tell, are the big factors our ear/brains use to determine the type of instrument playing a note? Transients. No, not the kind that hang out in dark alleys, but the kind we see at the beginning of each note played.