Temple blocks are a set of idiophonic percussion instruments characterized by their hollowed-out, bulbous shape and resonant, "knocking" timbre. They are traditionally made from wood, such as camphor or maple, though modern versions are frequently constructed from high-density synthetic materials to increase durability and consistency of tone.
The instruments originated in East Asia, where they are known as muyü in China, mokugyo in Japan, and moktak in Korea. In their original cultural and religious contexts, these blocks are often carved in the shape of a stylized fish—a symbol of wakefulness in Buddhist tradition—and are used to maintain a steady rhythmic pulse during the chanting of sutras in Buddhist and Taoist rituals.
Temple blocks were integrated into Western music during the early 20th century. They were initially popularized in the United States within ragtime and early jazz "trap sets" before becoming a standard fixture in the orchestral percussion section and modern percussion ensembles. In Western arrangements, they are typically used in sets of five, mounted on a single stand and arranged in order of size.
While temple blocks are generally considered instruments of indefinite pitch, they are graduated to provide a relative melodic contour. A standard set of five is often tuned to approximate a pentatonic scale. The sound is produced by striking the block with a mallet, usually one with a rubber or yarn head. The resulting tone is deeper and more hollow than that of the standard rectangular woodblock, a quality attributed to the instrument’s large internal resonating cavity and narrow slit.