Voicing for a computor organ

Claim 2

In a musical instrument of the type including generation means for computing in real time the amplitudes at successive sample points of a musical waveshape, and a converter for converting said waveshape amplitudes to musical signals as the computations are carried out, said generation means including circuitry for individually calculating the constituent Fourier components of that musical waveshape and an accumulator for summing these Fourier components to obtain each waveshape amplitude, the relative amplitudes of said Fourier components with respect to each other being established by a set of harmonic coefficients, the improvement comprising; means for adding to one of said harmonic coefficients a single binary word consisting of all binary 0''s and a single binary 1bit to produce a transient voice having a relative amplitude established by the position of said single 1-bit within said word, said transient voice having a substantially sinusoidal waveshape.

Claim 3

In a musical instrument of the type including generation means for computing in real time the amplitudes at successive sample points of that waveshape, and a converter for converting said waveshape amplitudes to a musical tone as the computations are carried out, said generation means including circuitry for individually calculating the constituent Fourier components of that musical waveshape, and an accumulator for summing these Fourier components to obtain each waveshape amplitude, the relative amplitudes of said Fourier components with respect to each other, and hence the voice of the produced musical tone, being established by a set of harmonic coefficients, said instrument being provided with several such sets of harmonic coefficients and with stop tab switches to permit selection of which of such provided sets is utilized by said generation means, the improvement for providing additional voices to said instrument comprising: storage means within said instrument for storing an optionally inserted set of harmonic coefficients, a switch for connecting said generation means to utilize the harmonic coefficients from said storage means when said switch is in one position and for connecting sAid generation means to utilize a set of harmonic coefficients provided in the instrument when said switch is in another position, and an external data insertion device for entering said optional set of harmonic coefficients into said storage means.

Claim 4

In a musical instrument of the type including generation means for computing in real time the amplitudes at successive sample points of that waveshape, and a converter for converting said waveshape amplitudes to a musical tone as the computations are carried out, said generation means including circuitry for individually calculating the constituent Fourier components of that musical waveshape, and an accumulator for summing these Fourier components to obtain each waveshape amplitude, the relative amplitudes of said Fourier components with respect to each other, and hence the voice of the produced musical tone, being established by a set of harmonic coefficients, said instrument being provided with several such sets of harmonic coefficients and with stop tab switches to permit selection of which of such provided sets is utilized by said generation means, the improvement for providing additional voices to said instrument comprising: storage means within said instrument for storing an optionally inserted set of harmonic coefficients, a switch for connecting said generation means to utilize the harmonic coefficients from said storage means when said switch is in one position and for connecting sAid generation means to utilize a set of harmonic coefficients provided in the instrument when said switch is in another position, and an external data insertion device for entering said optional set of harmonic coefficients into said storage means.

Claim 5

In a musical instrument of the type including generation means for synthesizing a musical waveshape by computing in real time the amplitudes at successive sample points of that waveshape, and a converter for converting said waveshape amplitudes to musical signals as the computations are carried out, said generation means including first circuitry for individually calculating the constituent Fourier components of that musical waveshape, and an accumulator for summing these Fourier components to obtain each waveshape amplitude the relative amplitudes of said Fourier components with respect to each other being established by a set of harmonic coefficients utilized by said first circuitry, each harmonic coefficient having the same order as the corresponding Fourier component, the improvement for dynamically modifying the voice of the produced musical signals, comprising: storage means for storing voice modification data each associated with a Fourier component of corresponding order, each such voice modification data designating the extent to which the relative amplitude of the corresponding Fourier component should be altered, access control means for supplying each voice modification data from said storage means in unison with calculation of the Fourier component of corresponding order, and modification means for modifying the harmonic coefficient of corresponding order in accordance with said supplied voice modification data, the modified harmonic coefficients being utilized by said generation means to establish the relative amplitude of the corresponding Fourier component.

Claim 6

In a musical instrument of the type including generation means for synthesizing a musical waveshape by computing in real time the amplitudes at successive sample points of that waveshape, and a converter for converting said waveshape amplitudes to musical signals as the computations are carried out, said generation means including first circuitry for individually calculating the constituent Fourier components of that musical waveshape, and an accumulator for summing these Fourier components to obtain each waveshape amplitude the relative amplitudes of said Fourier components with respect to each other being established by a set of harmonic coefficients utilized by said first circuitry, each harmonic coefficient having the same order as the corresponding Fourier component, the improvement for dynamically modifying the voice of the produced musical signals, comprising: storage means for storing voice modification data each associated with a Fourier component of corresponding order, each such voice modification data designating the extent to which the relative amplitude of the corresponding Fourier component should be altered, access control means for supplying each voice modification data from said storage means in unison with calculation of the Fourier component of corresponding order, and modification means for modifying the harmonic coefficient of corresponding order in accordance with said supplied voice modification data, the modified harmonic coefficients being utilized by said generation means to establish the relative amplitude of the corresponding Fourier component.

Claim 7

A musical instrument according to claim 3 wherein said voice modification comprises addition of a transient voice, and wherein; said storage means comprises a register containing a single transient voice related harmonic coefficient of a specified order, wherein said access control means comprises a comparator for comparing the order of the Fourier component presently being calculated with the order of said single transient voice related coefficient, and gate means for supplying said transient voice related coefficient from said register to said modification means when said comparator detects identity between the compared orders, and wherein said modification means comprises an adder for adding said transient voice related coefficient to the harmonic coefficient of corresponding order.

Claim 8

A musical instrument according to claim 4 wherein said transient voice related coefficient consists of a binary word having a single binary ''''1'''' bit, the position of said 1-bit in said word establishing the relative amplitude of the transient voice, further comprising: transient voice amplitude control means for altering the position of said single 1-bit in said register to control the relative amplitude of said transient voice.

Claim 9

A musical instrument according to claim 5 wherein said register comprisies a shift register, and wherein amplitude control means comprises; shift means for shifting the contents of said register at controlled time intervals.

Claim 10

A musical instrument according to claim 3 wherein said voice modification comprises addition of a transient voice, wherein said storage means contains a set of transient voice related harmonic coefficients of different order, and wherein said modification means comprises an adder for adding each supplied transient voice related coefficient to the harmonic coefficient of corresponding order.

Claim 11

A musical instrument according to claim 7 wherein said transient voice produces a chiff effect, and wherein the only transient voice related harmonic coefficient of non-negligible value in said set is tHat coefficient associated with the Fourier component contributing a third or fifth harmonic to said musical waveshape.

Claim 12

A musical instrument according to claim 7 together with; means for altering the values of the transient voice related harmonic coefficients contained in said storage means at controlled time intervals.

Claim 13

A musical instrument according to claim 3 wherein said voice modification comprises modification of the harmonic content of said musical signals, wherein: said storage means comprises a shift register storing a set of binary bits each associated with a particular Fourier component order, the value of each bit designating whether or not the correspondidng Fourier component is to be included in the waveshape amplitude summation, and wherein said modification means comprises a gate for enabling the associated harmonic coefficient to be utilized by said generation means if the corresponding bit is of one binary value, and for providing a zero-valued harmonic coefficient to said generation means if the corresponding bit is of the other binary value.

Claim 14

A musical instrument according to claim 10 further comprising; means for loading different sets of binary bits into said shift register at controlled time intervals, so that during attack the value nmin is decreased progressively with time, where nmin is the lowest Fourier component order included in the waveshape amplitude summation during attack, and so that during decay the value nmax is increased progressively with time, where nmax is the highest Fourier component order included in the summation during decay.

Claim 15

A musical instrument according to claim 3 wherein said voice modification comprises modulation of the harmonic content of said musical signals, wherein said storage means comprises a plurality of memories each containing a set of attack/decay amplitude scale factors associated with a respective Fourier component order, wherein said access control means is time controlled to access different scale factors from said memories at different times during waveshape generation, and wherein said modification means comprises a scaler for multiplying each harmonic coefficient by the scale factor currently accessed from the memory that stores factors of corresponding order.

Claim 16

A musical instrument according to claim 3 together with an external data insertion device operatively connected to said first circuitry for providing said set of harmonic coefficients to said musical instrument, said provided harmonic coefficients being utilized by said generation means to establish the tonal quality of the generated musical signals.

Claim 17

In a musical instrument of the type having: first means for computing the Fourier components of a periodic complex waveshape at successive sample points, said Fourier components being computed separately for each sample point, said computations occurring at a clock rate independent of the period of said waveshape, the computed Fourier components having different respective orders n between a minimum order nmin and a maximum order nmax, accumulator means for adding the component values calculated by said first means to obtain the waveshape amplitude at said each sample point, and means for providing musical notes from the waveshape amplitudes obtained in said accumulator means, and wherein said first means comprises: note selection means including keyboard switches for selecting a frequency number establishing the separation between successive sample points, said number thereby establishing the period of the resultant musical note, a note interval adder, operative during each successive amplitude computation, to add said selected number of the sum previously contained in said note interval adder, the resultant contents of said note interval adder representing the sample point for which said waveshape amplitude Is computed, means for obtaining a trigonometric value, the argument of said trigonometric value being the product of the said sample point designated by the contents of said note interval adder times the order of the Fourier component presently being calculated, a harmonic coefficient memory storing a set of harmonic coefficient values designating the relatiive amplitude of each constituent Fourier component of a principal tone with respect to the amplitudes of the other constituent Fourier components of that tone, and a multiplier for multiplying each obtained trigonometric value by the modified harmonic coefficient of order corresponding to that of the Fourier component presently being calculated the products of such multiplication being the calculated Fourier component values which are added by said accumulator means to obtain the sample point amplitudes, the improvement for modifying the tonal quality of the provided musical notes during portions of note production, comprising; attack and decay signal means, responsive to depression and release of any keyboard switch, for providing respective start of attack and start of decay signals, and modification means for modifying the harmonic coefficients accessed from said harmonic coefficient memory as a function of time during the attack or decay periods initiated respectively by said start of attack and start of decay signals, the resultant modified harmonic coefficients being supplied to said multiplier.

Claim 18

In a musical instrument of the type having: first means for computing the Fourier components of a periodic complex waveshape at successive sample points, said Fourier components being computed separately for each sample point, said computations occurring at a clock rate independent of the period of said waveshape, the computed Fourier components having different respective orders n between a minimum order nmin and a maximum order nmax, accumulator means for adding the component values calculated by said first means to obtain the waveshape amplitude at said each sample point, and means for providing musical notes from the waveshape amplitudes obtained in said accumulator means, and wherein said first means comprises: note selection means including keyboard switches for selecting a frequency number establishing the separation between successive sample points, said number thereby establishing the period of the resultant musical note, a note interval adder, operative during each successive amplitude computation, to add said selected number of the sum previously contained in said note interval adder, the resultant contents of said note interval adder representing the sample point for which said waveshape amplitude Is computed, means for obtaining a trigonometric value, the argument of said trigonometric value being the product of the said sample point designated by the contents of said note interval adder times the order of the Fourier component presently being calculated, a harmonic coefficient memory storing a set of harmonic coefficient values designating the relatiive amplitude of each constituent Fourier component of a principal tone with respect to the amplitudes of the other constituent Fourier components of that tone, and a multiplier for multiplying each obtained trigonometric value by the modified harmonic coefficient of order corresponding to that of the Fourier component presently being calculated the products of such multiplication being the calculated Fourier component values which are added by said accumulator means to obtain the sample point amplitudes, the improvement for modifying the tonal quality of the provided musical notes during portions of note production, comprising; attack and decay signal means, responsive to depression and release of any keyboard switch, for providing respective start of attack and start of decay signals, and modification means for modifying the harmonic coefficients accessed from said harmonic coefficient memory as a function of time during the attack or decay periods initiated respectively by said start of attack and start of decay signals, the resultant modified harmonic coefficients being supplied to said multiplier.

Claim 19

A musical instrument according to claim 14 wherein said tonal quality is modified by the addition to said principal tone of a transient voice, said modification means comprising: a storage device containing at least one transient-voice-related harmonic coefficient, and an adder for adding each transient-voice-related harmonic coefficient to the principal-tone-related harmonic coefficient of corresponding order to obtain a modified harmonic coefficient that is utilized by said multiplier during calculation of the Fourier component value of corresponding order.

Claim 20

A musical instrument according to claim 15 together with; a transient duration counter, responsive to the contents of said note interval adder, for counting the number of fractional cycles of the provided musical note that have been generated since occurrence of said start of attack signal, and means for changing the values of the transient-voice-related harmonic coefficients in said storage device in response to the count of said transient duration counter.

Claim 21

A musical instrument according to claim 16 wherein said storage device is a register storing a single transient-voice-related harmonic coefficient that is added to the principal-voice-related harmonic coefficient of corresponding order for a period of time established by said transient duration counter, resulting in the production of a transient voice of substantially sinusoidal waveshape.

Claim 22

A musical instrument according to claim 17 wherein said single transient-voice-related harmonic coefficient consists of a binary number having a single binary 1 bit, together with clock means for shifting the position of said single 1 bit in said number, and hence changing the relative amplitude of the transient voice, as a function of time.

Claim 23

A musical instrument according to claim 15 together with; an attack scale factor memory containing a set of attack scale factors that establish the amplitude envelope of the generated principal tone during attack, attack memory access control circuitry, initiated by said start of attack signal and responsive to the number of cycles of the generated tone, for accessing successive attack scale factors from said scale factor memory, and a scaler for scaling the modified harmonic coefficients by the scale factor value currently accessed by said control circuitry prior to utilization of said modified harmonic coefficient by said multiplier.

Claim 24

A musical insTrument according to claim 19 wherein the summed transient-and principal-voice-related harmonic coefficients from said adder are scaled by said scaler, so that the combined principal tone and transient voice both have an envelope established by said stored attack scale factors.

Claim 25

A musical instrument according to claim 19 wherein only said principal-voice-related harmonic coefficient is scaled by said scaler prior to addition to said transient-voice-related harmonic coefficient in said adder, so that only the principal tone but not the transient voice has an envelope established by said stored attack scale factors.

Claim 26

A musical instrument according to claim 14 wherein said tonal quality is modified by selectively, programmatically deleting certain Fourier components from each waveshape amplitude computation during attack and decay, and wherein said modification means comprises: a storage device containing a single binary word having one binary digit associated with each Fourier component that can be included in each waveshape amplitude computation, a gate, operative as each harmonic coefficient is accessed from said harmonic coefficient memory, for permitting said accessed harmonic coefficient to be utilized by said multiplier if the associated binary digit is of one binary value and for providing a zero-valued harmonic coefficient to said multiplier if the associated binary digit is of the other binary value, and time controlled means, initiated by said start of attack or start of decay signals, for selectively altering said single binary word at certain time intervals during attack and/or decay.

Claim 27

A musical instrument according to claim 22 wherein: said storage device comprises a shift register that is shifted in unison with the accessing of said harmonic coefficient memory, the contents of one position of said shift register being used to control the enabling of said gate, and wherein said time controlled means comprises a counter, reset by said start of attack and start of decay signals and responsive to the contents of said note interval adder, that counts the number of cycles of fractional cycles of the principal tone that have been generated since the start of attack or decay, and load circuitry for entering different binary words into said shift register when the counter reaches certain preset count values.

Claim 28

A musical instrument according to claim 23 wherein said load circuitry enters data into said shift register that cause the value of the minimum order nmin to be decreased progressively during attack, and that cause the value of the maximum order nmax to be decreased progressively during decay.

Claim 29

A musical instrument according to claim 24 further comprising circuitry for preventing such alteration of constituent Fourier component minimum and maximum order when a principal tone having a substantially sinusoidal waveshape is being generated.

Claim 30

A musical instrument according to claim 14 wherein said modification means comprises; separate attack/decay scale factor memories each containing a set of attack/decay amplitude scale factors associated with a respective Fourier component order, time dependent access control means, initiated by said start of attack and start of decay signals, for accessing different scale factors from each attack/decay scale factor memory at different times during attack and decay, and a harmonic coefficient scaler for multiplying each harmonic coefficient accessed from said harmonic coefficient memory by the currently accessed attack/decay scale factor of corresponding order.