Wind capsule
A wind capsule is an attachment that is used for double reed instruments and, more rarely, also for single reed instruments, which completely encloses the reed so that it can vibrate freely in the wind capsule. The air is supplied through an opening in the wind capsule. The wind capsule serves both as a mouthpiece for more comfortable playing of the instrument and as protection for the sensitive reed . The use of a wind cap also changes the sound of the instrument, which is by design. It usually becomes louder and richer in overtones because the reed vibrates freely and cannot be controlled by the player with his lips. A similar effect occurs when the jaws are inflated, in which the reed swings freely in the oral cavity. Experienced players are able to influence the tone of a wind capsule instrument within the scope of the technical possibilities.
Typical wind capsule instruments with a characteristic sound are the Krummhorn , the Rauschpfeife and the various bagpipes .
In some traditional single-reed instruments such as the Indian tarpu with a play tube, the pungi with two cylindrical tubes and the razem from northeast India with seven, a larger wind capsule, which mostly consists of a bottle gourd , distributes the air over all the tubes.