Raigen 賴驗 (also written 頼驗), Tendai shōmyō scholar of the Kamakura period. Precise lifedates are not securely attested in modern reference works; he is conventionally placed in the period c. 1200–1300 on the basis of doctrinal vocabulary in his Onritsu shōkeshū KR6t0427. The work is distinctive in integrating Buddhist musical pitch-theory with esoteric Shingon-Tendai doctrine, reading the pitch-pipe relations as expressions of the dharma-realm and the singer’s intonation as devotional-cosmological practice. The DILA authority id is A001261.