Chin rest

A chinrest is a shaped piece of wood (or plastic) attached to the body of a violin or a viola to aid in the positioning of the player's jaw or chin on the instrument. The chinrest may be made of ebony, rosewood, boxwood, or plastic. It was invented by Louis Spohr in the early 19th century; historically, this has been explained as a response to increasingly difficult repertoire which demanded freer left hand techniques than had previously been used; however, Spohr intended his small block attached to the bout to protect the tailpiece, which he reportedly broke with his vigorous playing. However, after being promoted by prominent violinists of the day, such as Pierre Baillot and Giovanni Battista Viotti, it gained quick acceptance among most violists & violinists and is today considered a standard part of the viola and violin.

The chinrest is attached to the instrument by one or two metal clamps that hook over the edge of the back. Two bottlescrews comprise the main parts of the clamp or clamps and provide slight tension to hold the chinrest in place. When attachment is by a single clamp, the two screws are joined by a metal bar that conforms to the back edge of the instrument, whereas "Hill-style" clamps are used in a pair, each clamp having its own foot and its own screw, with no bar joining them. The clamps and the chinrest itself are usually padded with cork or felt where they contact the instrument to minimize damage to the wood.

The two screws may both be placed on the shoulder side of the instrument, or one may be placed on each side of the endpin so that the chinrest straddles the tailgut. The latter may be considered a safer installation, as the clamps get support from the bottom block, and there is less chance that overtightening will cause damage.

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