COMPOSITE TONE SLIDING PORTAMENTO DEVICE WITH INDEPENDENT ADSR MODULATION

摘要

A keyboard operated musical instrument is disclosed having a portamento effect controlled from a portamento keyboard consisting of a linear array of keyswitches. The keyswitches are arranged in groups corresponding to each musical note and spaced so that a number of contiguous switches are actuated by each finger in contact with the portamento keyboard. Apparatus is provided for generating a frequency number corresponding to the closest switch actuated by the center of each finger thereby providing polyphonic portamento effects as the finger positions are slid along the portamento keyboard. An ADSR generator is used to provide envelope modulations initiated when a new finger has been detected on the slide wire and when a finger has been removed. A priority logic using frequency differences is used to distinguish between new fingers or the changes in position of a finger already in contact with the slide wire.