I am constantly stunned when I listen to a new guitarist make sweet music, and yet I am also always amazed by the music that bands such as Led Zeppelin made previously. So how do all of these bands make sound that is pleasing to our ears? Well, physics takes its part in melody making! Although we didn't cover it this year, sound waves were one of my favorite unit of physics (probably because I got to bring my guitar in last year to demonstrate harmonics). Guitars can be tuned so that there is a frequency differential between the strings. Some intervals of frequency, such as perfect fourths and fifths, are pleasing to the human ear, while others are very dissident. Also, the 12th fret on a guitar has special qualities; being a complete perfect octave above the open string, it is the first harmonic, and therefore can be played with a very interesting noise. Go Physics!!!!