Electronic music synthesizer

摘要

An electronic music synthesizer capable of simulating a wide variety of musical effects, wherein the settings which create the various effects are hard wired on a plurality of selectable circuit boards so that programming of the instrument can be accomplished by the player with minimum effort. The synthesizer encodes a plurality of keys on the keyboard and selects a tone from the tone generator corresponding to the depressed key. This tone is fed through a chain of dividers to create the needed footages, which are then fed to voicing cards that create the different tone sources for the synthesizer. These tone sources are fed into a state variable active filter which modifies the timbre of the tone sources in order to achieve the desired frequency-related effects. The output of the filter is fed to a gain module wherein the amplitude envelope has a controlled attach and decay as well as several different modes of operation such as steady state and percussive, which are selected by means of multiple bit binary words produced at the preprogrammed circuit board. The operating frequency of the filter is controlled by an envelope generator preset in a percussive mode to have a predetermined envelope. All controls for the synthesizer are preset from the voice boards, which are individually connected in the circuit either by tab switch operation or by physically inserting the voice board in a player accessible connector.