The Double Bass
The double bass, also known as the string bass is the largest instrument of the string family, stands at 6ft (around 180cm) from top to bottom and is typically constructed from wood. The double bass is commonly found in orchestras and string ensembles but is also an ever present instrument in jazz bands, traditional rock and roll bands and country and western groups. Of course, many rock, rap and pop groups adopt the electric bass guitar which generates volume and a provides a "different sound" altogether to the double bass and more suited to the music genre.
The double bass can be plucked (like a guitar) or bowed (like a violin). Jazz and blues will almost exclusively utilise plucking whilst other music types, especially the orchestra will make extensive use of bowing. Many modern bands will need to amplify the double bass whereas the orchestra and ensembles will more often rely on the natural acoustic sound and volume generated by the double bass.
Unlike other instruments of the string family the double bass player stands or sits on a high stool, and leans the instrument against their body, turning the double-bass inward in order to reach the strings and in order to facilitate this the double bass has sloping shoulders and at the foot of the instrument is the "end pin", a metal rod with a spiked or rubberised tip which takes the weight of the double bass. One other major difference between the double bass and other members of the string family is the use of metal machine heads where the tuning machine turns a metal worm to drive a gear in order to tune the strings whereas other instruments rely on friction pegs.
The double bass is a transposing instrument and sounds one octave lower than written (to avoid writing ledger lines) with strings usually tuned to E, A, D and G, which you will note is in fourths rather than fifths unlike most other modern orchestral string instruments.