Timpani (Kettle Drums)
Timpani is the Italian word for kettle-drums, which are tuneable drums used in the symphony orchestra.
The tension of the skin membrane can be adjusted by the player, to tune each
drum to a particular bass note. There are usually three kettle drums in the
orchestra, tuned to the tonic, dominant and sub-dominant notes for the key
of the music being played. There are 4 main sizes of kettle-drum, but the middle two (26 inch and 29 inch) are the most used. These are optimized for pitch rangees between F2 and F3.