Musical tone synthesizing apparatus using wave guide synthesis

A musical tone synthesizing apparatus for synthesizing musical tones comprising:

• (a) closed-loop means functioning as a closed loop circuit and including delay means having a delay interval corresponding to a pitch of the musical tone to be generated, wherein a signal is circulated in the closed-loop circuit to create a standing wave and the circulating signal is picked up from the closed-loop circuit as a tone signal;
• (b) conversion means for converting a first signal representative of a first physical property into a second signal representative of a second physical property related to the first physical property;
• and
• (c) excitation means for creating an excitation signal responsive to an output of the closed-loop means and to an output of the conversion means, wherein the excitation signal from the excitation means is coupled tot he conversion means thereby to constitute a feedback loop around the excitation means separate from the closed-loop, the excitation means supplying the created excitation signal into the closed-loop means to affect signal circulation in the closed loop circuit.

A musical tone synthesizing apparatus comprising:

• a loop circuit including delay means having a predetermined delay interval corresponding to the pitch of a tone to be synthesized, wherein a signal is circulated in the loop circuit to create a standing wave, and wherein a signal is picked up from the loop circuit as a tone signal;
• excitation means for creating an excitation signal in response to an output of the closed-loop circuit and an externally provided control signal and providing the excitation signal to the loop circuit to affect signal circulation in the loop circuit;
• and
• a feedback loop separate from the loop circuit which receives the excitation signal and generates the control signal in response thereto, whereby a feedback loop is created around the excitation means.