Electronic synthesis of sounds employing fundamental and formant signal generating means

Claim 2

A sound generating system comprising: fundamental frequency signal generating means for generating signals of a fundamental frequency defining the pitch of sounds to be synthesized; and at least one formant frequency signal generating means connected to said fundamental frequency signal generating means for producing signals of formant frequency associated with said sounds to be synthesized and being higher in frequency than said fundamental frequency, said formant frequency signal generating means starting its output generation in synchronism with output signals from said fundamental frequency signal generating means, and stopping its output generation at predetermined time during the period of said fundamental frequency signal to produce at the output of said formant frequency signal generating means signals including a component corresponding to said fundamental frequency for defining the pitch of said sound to be synthesized and harmonic components of said fundamental frequency component forming at least one formant included in said sounds to be synthesized.

Claim 3

A sound generating system according to claim 1 further comprising means for controlling the frequency of at least one of said fundamental frequency signal generating means and said formant frequency signal generating means.

Claim 4

A sound generating system according to claim 2 wherein said means for controlling the frequency comprises means for generating a control voltage signal of a low frequency to control said at least one signal generating means repeatedly.

Claim 5

A sound generating system according to claim 2 wherein said means for controlling the frequency comprises manually operable control means; and means for producing a transient control voltage signal in response to the operation of said manually operable control means to control said at least one signal generating means transiently.

Claim 6

A sound generating system according to claim 4 wherein said manually operated means includes the keyboard of an electronic musical instrument, and wherein the transient control voltage signal is generated in response to depression of a key of said keyboard.

Claim 7

A sound generating system according to claim 1 comprising a monostable multivibrator, which is controllable in its output pulse width, connected between said fundamental and formant frequency signal generating means; and means connected to said monostable multivibrator for generating a multivibrator output pulse control signal of a low frequency to control repeatedly the duration of said formant frequency signals from said formant frequency signal generating means responsive to said output pulses of said monostable multivibrator.

Claim 8

A sound generating system according to claim 1 comprising manually operable control means; a monostable multivibrator, which is controllable in its output pulse width, connected between said fundamental and formant frequency signal generating means; and means coupled to said manually operated control means and to said monostable multivibrator for generating a transient multivibrator output pulse width control signal in response to the operation of said manually operable control means to control transiently the duration of said formant frequency signals from said formant frequency signal generating means responsive to said output pulses of said monostable multivibrator.

Claim 9

A sound generating system according to claim 1 wherein said at least one formant frequency signal generating means includes an oscillator, the oscillations of which are started in synchronism with output signals from said fundamental frequency signal generating means.

Claim 10

A sound generating system comprising: first generating means for generating signals having a frequency equal to an integral multiple of a fundamental frequency defining the pitch of sounds to be synthesized; divider means connected to said generating means for producing signals of said fundamental frequency; first formant signal generating means connected to said first generating means for generating signals of high formant frequency associated with said sounds to be synthesized which is higher in frequency than said fundamental frequency, said first formant signal generating means starting its output generation in synchronism with output signals from said first generating means, and stopping its output generation at a predetermined time during the period of said signals having the frequency equal to the integral multiple of said fundamental frequency; second formant signal generating means connected to said divider means for producing formant frequency signals associated with said sounds to be synthesized which are lower in frequency than said high formant frequency and higher in frequency than said fundamental frequency, said second formant signal generating means starting its output generation in synchronism with output signals from said divider means, and stopping its output generation at a predetermined time during the period of said fundamental frequency signals; and means for mixing output signals from first and second formant signal generating means to produce at the output of said mixing means signals including a component corresponding to said fundamental frequency for defining the pitch of sounds to be synthesized and harmonic components of said fundamental frequency component forming formants included in said sounds to be synthesized.

Claim 11

A sound generating system comprising: first generating means for generating signals having a frequency equal to an integral multiple of a fundamental frequency defining the pitch of sounds to be synthesized; divider means connected to said generating means for producing signals of said fundamental frequency; first formant signal generating means connected to said first generating means for generating signals of high formant frequency associated with said sounds to be synthesized which is higher in frequency than said fundamental frequency, said first formant signal generating means starting its output generation in synchronism with output signals from said first generating means, and stopping its output generation at a predetermined time during the period of said signals having the frequency equal to the integral multiple of said fundamental frequency; second formant signal generating means connected to said divider means for producing formant frequency signals associated with said sounds to be synthesized which are lower in frequency than said high formant frequency and higher in frequency than said fundamental frequency, said second formant signal generating means starting its output generation in synchronism with output signals from said divider means, and stopping its output generation at a predetermined time during the period of said fundamental frequency signals; and means for mixing output signals from first and second formant signal generating means to produce at the output of said mixing means signals including a component corresponding to said fundamental frequency for defining the pitch of sounds to be synthesized and harmonic components of said fundamental frequency component forming formants included in said sounds to be synthesized.

Claim 12

A sound generating system comprising: fundamental frequency signal generating means for generating signals of a fundamental frequency defining the pitch of sounds to be synthesized; formant frequency signal generating means including a voltage controlled variable frequency oscillator means connected to said fundamental frequency signal generating means for producing signals of formant frequency associated with sounds to be synthesized which is higher in frequency than said fundamental frequency, said formant frequency signal generating means starting its oscillation in synchronism with output signals from said fundamental frequency signal generating means, and stopping its oscillation at a predetermined time during the period of said fundamental frequency signal; and means connected to said fundamental frequency signal generating means for shaping the wave form of output signals from said fundamental frequency signal generating means and supplying the shaped output signals to said voltage controlled variable frequency oscillator means to control the frequency thereof.

Claim 13

A sound generating system comprising: fundamental frequency signal generating means for generating signals of a fundamental frequency defining the pitch of sounds to be synthesized; formant frequency signal generating means including a voltage controlled variable frequency oscillator means connected to said fundamental frequency signal generating means for producing signals of formant frequency associated with sounds to be synthesized which is higher in frequency than said fundamental frequency, said formant frequency signal generating means starting its oscillation in synchronism with output signals from said fundamental frequency signal generating means, and stopping its oscillation at a predetermined time during the period of said fundamental frequency signal; and means connected to said fundamental frequency signal generating means for shaping the wave form of output signals from said fundamental frequency signal generating means and supplying the shaped output signals to said voltage controlled variable frequency oscillator means to control the frequency thereof.

Claim 14

A sound generating system according to claim 10 wherein the output of said shaping means is a saw-tooth wave whose voltage varies, said saw-tooth wave varying the frequency of output signals from said voltage controlleD variable frequency oscillator means.

Claim 15

A sound generating system according to claim 10 wherein the output of said shaping means is a stepped wave whose voltage varies in a step-wise manner, said stepped wave varying the frequency of output signals from said voltage controlled variable frequency oscillator means, thereby producing a plurality of formants of different frequencies.

Claim 16

A sound generating system according to claim 9 wherein said first and second formant frequency signal generating means include an oscillator generating oscillating output signals.