The Triforium is the name of a six story 60 ton public sculpture in the Los Angeles Mall Civic Center complex, located at the intersection of Temple and Main Streets in Downtown Los Angeles. The Mall's architect Robert Stockwell commissioned artist Joseph Young to create the sculpture and it was installed in 1975. Young's original plans called for the piece to be a Kinetic sculpture, which would use motion sensors and a computer controlled system to detect and translate the motions of passerby into patterns of light and sound displayed by the prisms and carillon. Young predicted that his artwork would eventually become know as "the Rosetta Stone of art and technology" and bragged that it was the world's first "polyphonoptic" tower. He also said that the Triforium was a tribute to the unfinished, kaleidoscopic nature of Los Angeles. In the original concept, Young intended for the sculpture to project laser beams into space, which would have made it the world's first astronomical beacon. Budgetary restrictions, however, curtailed this design element. The initial cost of the sculpture was $925,000 and it was dedicated on December 12, 1975 although an electrical snafu delayed the musical portion's debut.

The Triforium incorporates three two-legged concrete pillars, each supporting a bank of multicolored glass prisms (1,494 in all), as well as a Gerhard Finkenbeiner electronic 79 note glass bell carillon with two octaves of English bells, and two octaves of Flemish bells, which were synchronized to lighting effects contained within the glass prisms. Meant to play "everything from Beethoven to the Bee Gees", the carillon was operated manually, or by computer. (less info)