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.
From Wikipedia, the free encyclopedia. A compound bow is a modern bow that uses a levering system, usually of cables and pulleys, to bend the limbs. The pulley/cam system grants the wielder a mechanical advantage, and so the limbs of a compound bow are much stiffer than those of a recurve bow or longbow. This rigidity makes the compound bow more energy-efficient than other bows, as less energy is dissipated in limb movement.