What is a hurdy-gurdy, and how does it work?
The hurdy-gurdy is a stringed instrument in which the strings are rubbed by a rosined wheel instead of a bow. The wheel is turned by the player’s right hand, while the left hand plays the tune on the keys in the keybox. Two of the strings (usually), called the chanters or melody strings, run though the keybox and their vibrating length is shortened by the key pressing against it. Several drone strings are outside the keybox, and thus sound the same note all the time. For this reason the hurdy-gurdy sounds similar to a bagpipe. A small movable bridge on one of the drones can be made to vibrate rhythmically by cranking the wheel harder, and this buzzing is used for a rhythmic accompanyment to the tune. A diagram of the parts is shown below.
