A late-1980s synth from Kawai; the first of their two attempts to commercialize additive synthesis. The K5 is a digital synth, built around two harmonic generators. Each generator was capable of producing a fundamental and the 2nd through 63rd harmonics for that fundamental. The two generators could have their fundamentals tuned to a desired interval, or they could be configured in a single-tone mode in which the second generator provided 63 additional harmonics for the first generator, extending the single tone to 126 harmonics.