A plurality of pad operating means for manual operation are provided on a keyboard panel of an electronic keyboard musical instrument. When an operator operates the pad operating means using the keyboard during melody play, an operation signal is supplied to a CPU, and a rhythm sound corresponding to...http://www.google.de/patents/US4972755?utm_source=gb-gplus-sharePatent US4972755 - Electronic musical instrument having automatic sound signal generation and a rhythm-play function based on manual operation
