Parametric signal modeling musical synthesizer

Claim 2

An electronic musical tone generator for generating an electrical output signal representing a musical tone in response to an input control signal, said musical generator comprising: an excitation signal generator responsive to said input control signal for generating an excitation signal; and a formant filter generator responsive to said input control signal for generating a time varying formant filter for filtering said excitation signal in a time varying manner to create the output tone signal; wherein said formant filter generator includes instrument parameter memory means for storing a plurality of sets of filter coefficients; intermediate parameter set generation means for deriving an intermediate filter coefficient set by interpolating between at least two of the sets of filter coefficients stored in instrument parameter memory based upon said input control signal; and time varying parameter generation means for interpolating within said intermediate filter coefficient set to generate said time varying formant filter.

Claim 3

The electronic musical generator of claim 1, further including: a tone amplitude envelope builder for building a tone amplitude envelope including: a multidimensional tone amplitude envelope memory for storing sets of data, each set for defining an envelope shape; and a tone amplitude envelope generator responsive to said input control signal for interpolating between at least two stored sets of data to generate a tone amplitude envelope; and means for combining said tone amplitude envelope with said filtered excitation signal.

Claim 4

The electronic musical generator of claim 2, wherein said formant filter generator is responsive to said tone amplitude envelope.

Claim 5

The musical generator of claim 1, further including a pitch envelope builder for building a pitch envelope, and wherein said excitation signal generator is responsive to said pitch envelope.

Claim 6

The musical generator of claim 1 wherein said control signal comprises initial pitch, initial intensity, and desired instrument.

Claim 7

The musical generator of claim 1 wherein said control signal comprises initial pitch, time-varying intensity, and desired instrument.

Claim 8

An electronic musical tone generator for generating an output tone signal representing a musical tone in response to an input control signal representing desired pitch, said musical generator comprising: an excitation signal generator responsive to said input control signal for generating an excitation signal; said excitation signal generator including a multidimensional table oscillator memory for storing sets of oscillator data; an oscillator selector and interpolator for selecting at least two of the sets of oscillator data according to said control signal and interpolating between said sets of oscillator data to form an intermediate oscillator data table; and a table lookup oscillator for reading out data from the intermediate oscillator data table over time; and a formant filter generator responsive to said input control signal for generating a formant filter for filtering said excitation signal in a time varying manner to create the pitched signal; said formant filter generator including a multidimensional filter coefficient set table memory for storing sets of filter coefficients; a filter coefficient sequencer and interpolator for selecting at least two of the sets of filter coefficients according to said control signal and interpolating between them to form a variable rate decimated filter coefficient sequence; and a time varying filter generator for interpolating among the coefficients forming the decimated filter coefficient sequence over time to generate a series of filter coefficient sets for use in creating said formant filter.

Claim 9

An electronic musical tone generator for generating an output tone signal representing a musical tone in response to an input control signal representing desired pitch, said musical generator comprising: an excitation signal generator responsive to said input control signal for generating an excitation signal; said excitation signal generator including a multidimensional table oscillator memory for storing sets of oscillator data; an oscillator selector and interpolator for selecting at least two of the sets of oscillator data according to said control signal and interpolating between said sets of oscillator data to form an intermediate oscillator data table; and a table lookup oscillator for reading out data from the intermediate oscillator data table over time; and a formant filter generator responsive to said input control signal for generating a formant filter for filtering said excitation signal in a time varying manner to create the pitched signal; said formant filter generator including a multidimensional filter coefficient set table memory for storing sets of filter coefficients; a filter coefficient sequencer and interpolator for selecting at least two of the sets of filter coefficients according to said control signal and interpolating between them to form a variable rate decimated filter coefficient sequence; and a time varying filter generator for interpolating among the coefficients forming the decimated filter coefficient sequence over time to generate a series of filter coefficient sets for use in creating said formant filter.

Claim 10

The musical generator of claim 7, wherein: said table lookup oscillator includes means for reading out one frame of oscillator data at a predetermined frame rate; said time varying filter generator includes means for generating a filter coefficient set at the predetermined frame rate; and said musical generator further including a window for retaining a second portion of each filtered excitation signal frame and adding the second portion to a first portion of a succeeding filtered excitation signal frame.

Claim 11

The musical generator of claim 7 wherein: said table lookup oscillator includes means for reading out one sample of oscillator data at a predetermined sample rate; and said time varying filter generator includes means for generating a filter coefficient set at the predetermined sample rate.

Claim 14

An electronic musical tone generator for generating an electrical output signal representing a musical tone in response to an input control signal, comprising: an oscillator table memory for storing a plurality of oscillator tables; means for generating an excitation signal, including means for selecting and interpolating between at least two oscillator tables stored in the oscillator table memory, based upon the input control signal, to form a new oscillator table, and means for generating an excitation signal based upon the new oscillator table; a filter coefficient data memory for storing sets of filter coefficients; means for interpolating between sets of filter coefficients stored in a filter coefficient memory based upon the input control signal to generate an intermediate filter coefficient set; means for interpolating within the intermediate filter coefficient set to generate a formant filter; and means for filtering the excitation signal with the formant filter to generate a tone.

Claim 15

An electronic musical tone generator for generating an electrical output signal representing a musical tone in response to an input control signal, comprising: an oscillator table memory for storing a plurality of oscillator tables; means for generating an excitation signal, including means for selecting and interpolating between at least two oscillator tables stored in the oscillator table memory, based upon the input control signal, to form a new oscillator table, and means for generating an excitation signal based upon the new oscillator table; a filter coefficient data memory for storing sets of filter coefficients; means for interpolating between sets of filter coefficients stored in a filter coefficient memory based upon the input control signal to generate an intermediate filter coefficient set; means for interpolating within the intermediate filter coefficient set to generate a formant filter; and means for filtering the excitation signal with the formant filter to generate a tone.

Claim 16

The musical tone generator of claim 11, further comprising: a noise signal generator for generating a noise signal; and means for combining the electrical output signal with the noise signal.

Claim 17

The musical tone generator of claim 12, wherein said noise signal generator comprises: a noise memory for storing sampled noise data; means for reading out the sampled noise data to generate the noise signal.

Claim 18

The musical tone generator of claim 13, further comprising means for reading out the noise signal at a variable rate.

Claim 19

The musical tone generator of claim 13, further comprising an amplitude envelope generator for generating an amplitude envelope, and means for combining the noise signal with the amplitude envelope.

Claim 20

The musical generator of claim 12 wherein said noise signal generator includes: a white noise generator for generating white noise; and a time-varying noise filter, responsive to said input control signal, for filtering the white noise.

Claim 21

The musical generator of claim 16 wherein said time-varying noise filter comprises: a multidimensional noise filter coefficient set memory for storing sets of filter coefficients; and means for selecting and interpolating among the sets of noise filter coefficients to form the noise filter.

Claim 22

The musical generator of claim 17 wherein said means for interpolating comprises: a noise filter coefficient sequencer and interpolator for interpolating between the filter coefficient sets to form a variable rate decimated filter coefficient sequence; and a time varying noise filter generator for interpolating over time among the coefficients forming the decimated filter coefficient sequence to generate a series of filter coefficient sets for use in generating the time varying noise filter.

Claim 23

The musical tone generator of claim 17, wherein said control signal includes a signal representing tone intensity.

Claim 24

The musical tone generator of claim 17 or 18, wherein said input control signal is a variable input control signal, and said means for selecting and interpolating selects and interpolates among the sets of noise filter coefficients in real time to generate a time varying sequence based upon said variable input control signal.

Claim 25

The musical tone generator of claim 20, wherein said variable input control signal includes a variable signal representing desired tone pitch.

Claim 26

The musical tone generator of claim 20, wherein said variable input control signal includes a variable signal representing desired tone intensity.

Claim 27

The musical generator of claim 20 wherein said noise signal generator further includes: a noise amplitude envelope generator; and means for combining the filtered white noise and the noise amplitude envelope.

Claim 28

The musical generator of claim 20 wherein said noise signal generator further includes: a noise pitch envelope generator for generating a noise pitch envelope; and means for combining the filtered white noise and the noise pitch envelope.

Claim 29

The musical generator of claim 17 or 18, wherein said sets of filter coefficients comprise time varying sequences of filter coefficients, and said means for selecting and interpolating generates a new time varying sequence.

Claim 30

The musical tone generator of claim 25, wherein said means for selecting and interpolating generates the entire new time varying sequence when said input control signal is first received.

Claim 31

The musical tone generator of claim 25, wherein said means for selecting and interpolating generates the new time varying sequence on an ongoing basis as the tone progresses.

Claim 32

An electronic musical tone generator for generating an electrical output signal representing a musical tone in response to an input control signal, comprising: means for generating an excitation signal; a filter coefficient data table memory for storing sets of filter coefficients; means for interpolating between sets of filter coefficients stored in the filter coefficient table memory based upon the input control signal to generate a formant filter; said means for interpolating including: a formant filter coefficient sequencer and interpolator for interpolating between the filter coefficient sets to form a variable rate decimated filter coefficient sequence; and a time varying formant filter generator for interpolating over time among the coefficients forming the decimated filter coefficient sequence to generate a series of filter coefficient sets for use in creating the time varying formant filter; and means for filtering the excitation signal with the formant filter to generate a tone.

Claim 33

An electronic musical tone generator for generating an electrical output signal representing a musical tone in response to an input control signal, comprising: means for generating an excitation signal; a filter coefficient data table memory for storing sets of filter coefficients; means for interpolating between sets of filter coefficients stored in the filter coefficient table memory based upon the input control signal to generate a formant filter; said means for interpolating including: a formant filter coefficient sequencer and interpolator for interpolating between the filter coefficient sets to form a variable rate decimated filter coefficient sequence; and a time varying formant filter generator for interpolating over time among the coefficients forming the decimated filter coefficient sequence to generate a series of filter coefficient sets for use in creating the time varying formant filter; and means for filtering the excitation signal with the formant filter to generate a tone.

Claim 34

The electronic musical tone generator of claim 28, wherein said means for generating an excitation signal includes: an oscillator table memory; means for storing a continuously varying single period excitation in the oscillator table memory; and means for repeatedly reading out the single period excitation from the oscillator table memory, thereby forming the excitation signal.

Claim 35

The electronic musical tone generator of claim 28, wherein said control signal includes a signal representing tone intensity.

Claim 36

The electronic musical tone generator of claim 28, wherein said input control signal is a time variable input control signal, and said means for selecting and interpolating selects and interpolates among the sets of formant filter coefficients in real time to generate a time varying sequence responsive to the variable input control signal.

Claim 37

The musical tone generator of claim 31, wherein said variable input control signal includes a variable signal representing input pitch.

Claim 38

The musical tone generator of claim 31, wherein said variable input control signal includes a variable signal representing input intensity.

Claim 39

The musical generator of claim 31 further including: an amplitude envelope generator; and means for combining the filtered excitation signal and the amplitude envelope.

Claim 40

The musical generator of claim 31 further including: a pitch envelope generator; and means for combining the filtered excitation signal and the pitch envelope.

Claim 41

The musical tone generator of claim 31, wherein said excitation signal generating means generates said excitation signal only once when said input control signal is first received.

Claim 42

The musical tone generator of claim 28, wherein said sets of filter coefficients comprise time varying sequences of filter coefficients, and said means for selecting and interpolating generates a new time varying sequence.

Claim 43

The musical tone generator of claim 37, wherein said means for selecting and interpolating generates the entire new time varying sequence when said input control signal is first received.

Claim 44

The musical tone generator of claim 38, wherein said excitation signal generating means generates said excitation signal only once when said input control signal is first received.

Claim 45

The musical tone generator of claim 37, wherein said means for selecting and interpolating generates the new time varying sequence on an ongoing basis over the duration of the tone.

Claim 46

The musical tone generator of claim 40, wherein said excitation signal generating means generates said excitation signal only once when said input control signal is first received.

Claim 47

An electronic musical tone generator for generating an electrical output signal representing a musical tone in response to an input control signal, comprising: a formant filter generator for generating a formant filter; an oscillator table memory for storing a plurality of oscillator tables; means for generating an excitation signal, including means for selecting and interpolating between at least two oscillator tables stored in the oscillator table memory, based upon the input control signal, to form a new oscillator table, and means for generating an excitation signal based upon the new oscillator table; means for providing the excitation signal to the formant filter at a desired data rate; and means for filtering the excitation signal with the formant filter to generate the tone signal.

Claim 48

An electronic musical tone generator for generating an electrical output signal representing a musical tone in response to an input control signal, comprising: a formant filter generator for generating a formant filter; an oscillator table memory for storing a plurality of oscillator tables; means for generating an excitation signal, including means for selecting and interpolating between at least two oscillator tables stored in the oscillator table memory, based upon the input control signal, to form a new oscillator table, and means for generating an excitation signal based upon the new oscillator table; means for providing the excitation signal to the formant filter at a desired data rate; and means for filtering the excitation signal with the formant filter to generate the tone signal.

Claim 49

The electronic musical tone generator of claim 42, wherein: said input control signal includes a time varying signal representing tone pitch; and the excitation signal generating means includes means for varying the excitation signal data rate responsive to the time varying signal representing tone pitch.

Claim 50

The electronic musical tone generator of claim 42, wherein said input control signal includes a time varying signal representing tone intensity; and further including: means for varying the gain of the excitation signal responsive to the time varying signal representing tone intensity.

Claim 51

The musical tone generator of claim 42, wherein said excitation signal generating means selects and interpolates only once when said input control signal is first received.

Claim 52

The electronic musical tone generator of claim 42, wherein said oscillator tables comprise continuously varying single period excitations, and said excitation signal generating means further includes means for repeatedly reading out the single period excitations to form the excitation signal.

Claim 53

The electronic musical tone generator of claim 46, wherein the control signal includes a signal representing tone pitch, and the excitation signal generating means selects and interpolates between oscillator tables according to the tone pitch signal.

Claim 54

The electronic musical tone generator of claim 46, wherein the control signal includes a signal representing tone intensity, and the excitation signal generating means selects and interpolates between oscillator tables according to the tone intensity signal.