The CE-2 was the first compact pedal chorus from Boss. The CE-1 was released 1976 and contained the exact same circuit as the Roland Jazz Chorus JC-120 Amp. The CE-2 builds on the legacy of the CE-1 but isn’t identical. The middle region is boosted in the CE-2 compared to the CE-1. According to the design engineers this may be because the CE-1 had a lower input impedance.
Roland says that they stopped marketing the CE-2 November 1982. The pedal was however still produced and sold at least out 1990. The label changed from black to green 1984. The CE-2 was produced in Japan up until 1988 when production moved to Taiwan.