Cello Bow

Traditionally, bows are made from pernambuco or brazilwood. Both come from the same species of tree (Caesalpina echinata), but pernambuco, used for higher-quality bows, is the heartwood of the tree and is darker in color than brazilwood (which is sometimes stained to compensate). Pernambuco is a heavy, resinous wood with great elasticity, which makes it an ideal wood for instrument bows.

Bows are also made from other materials, such as carbon-fibre—stronger than wood—and fiberglass (often used to make inexpensive, low-quality student bows). An average cello bow is 73 cm long (shorter than a violin or viola bow) 3 cm high (from the frog to the stick) and 1.5 cm wide. The frog of a cello bow typically has a rounded corner like that of a viola bow, but is wider. A cello bow is roughly 10 grams heavier than a viola bow, which in turn is roughly 10 grams heavier than a violin bow.

Bow hair is traditionally horsehair, though synthetic hair, in varying colors, is also used. Prior to playing, the musician tightens the bow by turning a screw to pull the frog (the part of the bow under the hand) back, and increase the tension of the hair. Rosin is applied by the player to make the hairs sticky. Bows need to be re-haired periodically.

Baroque style (1600–1750) cello bows were much thicker and were formed with a larger outward arch when compared to modern cello bows. The inward arch of a modern cello bow produces greater tension, which in turn gives off a louder sound.

The cello bow has also been used to play guitars. Jimmy Page pioneered its application on tracks such as "Dazed and Confused." The post-rock Icelandic band Sigur Rós' lead singer often plays a guitar using a cello bow.

In 1989, the German cellist Michael Bach began developing a curved bow, encouraged by John Cage, Dieter Schnebel, Mstislav Rostropovich and Luigi Colani: and since then many pieces have been composed especially for it. This curved bow (BACH.Bow) is a convex curved bow which, unlike the ordinary bow, renders possible polyphonic playing on the various strings of the instrument. The solo repertoire for violin and cello by J. S. Bach the BACH.Bow is particularly suited to it: and it was developed with this in mind, polyphonic playing being required, as well as monophonic.