Tone signal generating apparatus of electronic musical instruments

摘要

Code data representing a plurality of note frequencies are stored in a first ROM and are selectively read out according to key operation of a keyboard. With the operation of a key, predetermined control data is also obtained, and this control data is cumulatively added to or subtracted from the code data as an initial value, whereby a note frequency signal corresponding to the operated key is obtained. Portions of the waveform of the resultant note frequency signal where there is a sharp change in amplitude are interpolated with a sine wave stored in a second ROM.