Sound effect imparting device for an electronic musical instrument

A device for imparting a frequency modulation effect to an input musical tone signal in an electronic musical instrument comprising:

• a first adder means,
• a second adder means,
• a first multiplier means,
• a second multiplier means,
• delay means for delaying output of said first adder means, and
• modulation information generating means for generating time varying modulation information corresponding to a frequency modulation type of sound effect to be imparted to a musical tone, said first adder means adding an input digital musical tone signal and the output of said second multiplier means, said second adder means adding the output of said first multiplier and the output of said delay means, said first multiplier means multiplying the output of said first adder means by said modulation information, said second multiplier means multiplies the output of said delay means by said modulation information, thereby obtaining a digital musical tone signal modulated by the output of said second adder means.

A sound effect imparting device for an electronic musical instrument comprising:

• first means having a memory means for sequentially storing respective sampled amplitude values of an input digital musical tone signal, a plurality of read-out means for reading the sampled amplitude values previously stored at different sampling times from said memory means, a plurality of multiplier means for multiplying the sampled amplitude values read by said read-out means by respective different reverberation coefficients, an an adder means for adding the multiplied values from said multiplier means, for forming an initial echo from the added value of said adder means, and
• second means having a digital delay means for delaying the input digital musical tone signal substantially by an initial echo generating time,
• first reverberation tone forming means for forming a first reverberation tone from the output of said digital delay means by regularly varying the amplitude level and the delay time thereof with a coarse delay time interval, and
• second reverberation tone forming means for forming, from the output of said first reverberation forming means, a second reverberation tone having a dense time interval as compared with said first reverberation tone, for forming a reverberation tone,
• said first means, said second means, and said first and second reverberation tone forming means all being entirely digital.