A countertenor is a type of classical male singing voice whose vocal range is equivalent to that of the female contralto or mezzo-soprano voice types.
Types of Compound Bows. Compound bows are classified by the type of cam system they use (called the bow eccentric.) The most popular types of compound bows on the market are Single Cam (sometimes also called One Cam or Solocam), Hybrid Cam, Dual Cam and Binary Cam. Less common designs like Quad Cam and Hinged are a little harder to find.
A bow typically consists of a length of wood with some other material stretched between its ends. The type of bow used to play the violin and related instruments has many hairs stretched between its ends, but bows used in other cultures often stretch a single piece of string between the ends of the wood.nexpensive bows often use nylon or synthetic hair. Rosin, which is sticky and made from tree sap, is regularly applied to the bow hair so that the bow moving across the instrument's strings will cause the string to vibrate and produce a tone.