Bak (hangul; hanja: ?) is a wooden clapper used in Korean court and ritual music. The person playing the bak is called jipbak, serving as the conductor or musical supervisor for the group. The bak creates the clapping sound if clapped to indicate when the music starts.
The bak is made of 6 flat wood boards that are about 13 1/2 in. x 2 3/4 in. The boards are tied together at one end with either string or cord to make a fan shape when spread out.
The jipak uses the bak to conduct the group, the same way a conductor uses a baton. The bak is sounded when the music starts and ends with three claps and when significant changes occur. For example, listening to the sound samples of Bak: Bak sounds