Electronic musical instruments

An electroic musical instrument wherein a musical tone is generated by repeatedly reading out amplitude values at sampling points in one period of a musical tone waveshape stord in a first waveshape memory device at a period corresponding to a tone pitch of a depressed key, said electronic musical instrument comprising;

• a second waveshape memory device for storing amplitude values at sampling points in one period of a new musical tone waveshape to be generated subsequent to said musical tone waveshape stored in said first waveshape memory device;
• first calculating means for calculating differences in amplitude values at sampling points stored in corresponding addresses of said first and second waveshape memory devices respectively;
• renewal rate control means for generating a waveshape renewal signal having a period corresponding to difference information produced by said first calculating means;
• and
• renewal means for effecting renewal of the memory content of said first waveshape memory device at a speed corresponding to the period of said waveshape renewal signal.