Kemençe is the common name for two very different instruments, one used in north Anatolian folk music, and the other in Turkish classical music. Names such as "pear-shaped kemençe" and "fasil kemençe" used until the mid-19th century eventually gave way to "classical kemençe."
History:
Until the 19th century, the Persian-derived word kemençe, meaning "small bow" or "small bowed instrument," was used for the spike fiddle known today as rebab. Also called kemân, the kemânçe was the only bowed instrument used in Turkish classical music until the late 18th century. The kemânçe gave way first to the viola d'amore and later to the European violin. The pear-shaped kemençe first entered the fasil ensemble in the mid-19th century.
STRUCTURE:
The classical kemençe is 40-41 centimeters in length and 14-15 centimeters wide. All its strings are of gut; only the yegâh string is silver-wound. Today some musicians use synthetic racquet strings, aluminum-wound gut or artificial silk strings, or chrome-wound steel violin strings. The sound post, which transmits the strings' vibration to the back of the instrument, is fixed between the bridge and back of the instrument under the neva string. A small hole, 3-4 mm in diameter, is drilled in the back of the instrument directly under the bridge.
One can safely say that the kemençe is the most-adorned of the Turkish instruments.