Ondekoza (鬼太鼓座) ("demon drum group"), sometimes referred to as "Za Ondekoza", is a Japanese troupe specializing in taiko drumming.
Founded in 1969 by Den Tagayasu, in Sado Island, Japan. Ondekoza was influential in the rise of the kumi-daiko (group taiko) style of taiko. Not a taiko player himself, Tagayasu helped transform taiko from a festival-based music form to a virtuosic performance art performed on stage. Ondekoza's performances in North America in 1975 was the first exposure for many and helped spread interest in taiko through North America. The now widely recognized style of wearing only a 'shimekomi' ('fundoshi loincloth) was originally started by Ondekoza when Pierre Cardin suggested that the physique of the drummer be exposed. The traditional Japanese drummers do not play only in underwear.
Part of a larger movement to rediscover Japanese folk art, Tagayasu brought together a group of young men and women to Sado Island to study and live. Largely without formal musical training, the original members lived communally in an old school house while studying taiko, shamisen, koto, minyo (folk music), and traditional dance. The lifestyle was austere and rigorous with most days beginning with a run before breakfast and filled with study and practice.
One of the keys to the groups success was the arrangement of traditional melodies and styles into stylized, artistic musical pieces. Examples of these are their songs yatai-bayashi, based on the Chichibu festival and hachijo and miyake based on the drum patterns from Hachijo Island and Miyake Island. Also groundbreaking was the Odaiko (Large Drum) solo, a musical piece focused largely on one performer with only minimal background drumming and percussion. Den Tagayasu and Ondekoza's arrangements of these pieces, and their associated playing styles, have been popularized by their widespread use by other taiko groups throughout Japan and the United States.