Fives

When I was an undergrad freshman, I stumbled into the campus chapel to hear the Messiah College Concert Choir directed by Linda Tedford. This was before I was a music major, I was by myself on my way to the library or something and decided on the spur of the moment to listen. When I sat and heard the tone of the choir I was immediately impressed. There was just something that I had never experienced before in that sound. The next year I auditioned and joined the choir (and the music department officially) and had some of the best times of my life there.

Looking back, the thing I heard was beautiful intonation. The perfect fifths and fourths were rock solid, but I don't think that would have made the impression. It must have been the major and minor thirds that were performed unlike anything I had previously heard. You see, as a piano player, I would have been used to hearing a close approximation to perfect fifths (the triple ratio), but the quintuple relationship would have been foreign to my equally-tempered ears.

Well tuned thirds are the primary difference between equal temperament and what is called Just Intonation. As I've explained earlier, equal temperament is a crude and artificial slicing of the octave(2:1) into twelve equal parts. Just Intonation however takes into account the ratios of 5:3, 5:4, 6:5, and 8:5 otherwise known as the minor third, major third, minor sixth, and Major sixth respectively. In a choir, string ensemble, and wind ensemble, performers can and should adjust each tone of the chromatic scale to accommodate different keys and tonalities. In other words, Just Intonation is fluid and flexible, which is highly inconvenient for fixed pitch instruments such as the piano and marimba but for these types of ensembles, it can be dramatic and... life-changing.