The group was founded by drummer Glen Sweeney, who had roots in Britain's free jazz scene, and had played with an avant-garde ensemble, the Sun Trolley. Sweeney described Third Ear's music as "electric acid raga," although the electricity was shut off shortly after they formed, when their electronic equipment was stolen. Sweeney simply molded Third Ear into an acoustic ensemble, with the addition of oboe, violin/viola, and cello. The personnel (with the exception of Sweeney) would rotate over the next few years; their early albums were produced by Andrew King, who had helped manage Pink Floyd in their early days. […] The original incarnation of Third Ear Band disbanded in the early '70s. Surprisingly, they re-formed in the late '80s, and released a few albums that boasted sounds and ambitions that were similar to those found in their early work. (AMG)
More info here.
Link in comments