Sounds of Music

Though this event is gone for now, it is likely to come back in future years so I might as well write down some basic information while it is still fresh in my mind.

Sounds of Music is an event in which two participants build two instruments, play two songs in a performance that's less than 4 minutes, and explain the physics of sound through an interview or written test.

The Instruments
There are four basic classifications of instruments. For the best score as possible in this event, you will need to build two instruments from different families.

Chordophones
In Chordophones, sound is produced by a vibrating string. The vibration of strings produces standing waves producing fundamental frequency as well as harmonics (the relative abundance of these make up the timbre of your instrument). Resonators added to the string will enhance the sound by vibrating sympathetically with them.

In chordophones, the wavelength made is twice the length of the string. Since we know that velocity equals frequency time wavelength, after assuming that the velocity of sound in the string will remain constant, we find that when one doubles length, frequency will be cut in half. Because the relationship between length and frequency is exponential we know that for every increment one goes up in a scale (1/12), the note increases by a factor of the 12th root of two. You can use this fact for starting your tuning. Unfortunately, you'll need some fine tuning and many hours to get your instrument to play accurate notes due to imperfections in string and to the fact that there will be different amount of tension on different strings (when playing different notes on single guitar string, there will be different amounts of tension). This will result in different velocities of sound in the string...making this form of tuning less reliable.

Examples of chordophones include
 * Guitars
 * Violins
 * Harps
 * Zithers
 * Lyres

Technical Interview
The following website provides much of the knowledge needed for the technical interview portion of sounds of music: http://www.phys.unsw.edu.au/jw/basics.html

Instrument Instructions
Here are websites with tutorials to make instruments:


 * Woodwinds
 * http://guido.gonzato.googlepages.com/whistle.html


 * Strings


 * Brass


 * Percussion
 * http://www.ehhs.cmich.edu/~dhavlena/xylo.htm