JP2897680B2 - Music signal generator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tone signal generator for reading a series of waveform samples discretely representing a tone waveform stored in a waveform memory at a speed corresponding to a pitch and outputting the tone signal as a tone signal. About.

[0002]

2. Description of the Related Art Conventionally, a series of waveform samples discretely representing a tone waveform has been stored in a waveform memory in advance, and a waveform sample stored in the waveform memory is sampled with a relatively low fixed frequency. In order to read out in synchronization with the clock signal, an address signal consisting of a plurality of bits that changes at a speed corresponding to the pitch of the generated musical tone and specifies a waveform sample is generated, and is specified by the upper bits of the address signal. A plurality of waveform samples near one waveform sample are read, and the plurality of waveform samples that have been read are interpolated using interpolation parameters that change according to the value of the lower bit of the address signal, and the interpolated waveform samples are read out. Is well known as a pitch asynchronous type tone signal generator which outputs a tone signal as a tone signal.

[0003]

However, in the above-described conventional apparatus, the interpolation function for defining the interpolation parameters is always the same even if the type of the waveform sample read from the waveform memory changes. Normally, the interpolation function inherently has a low-pass filter characteristic, and interpolation of a waveform sample is equivalent to passing a tone signal through a low-pass filter. Therefore, an interpolation function that sufficiently passes high-frequency components is used. For example, a tone signal having a harmonic component exceeding half of the sampling clock frequency contains a large amount of aliasing noise. On the other hand, if an interpolation function that allows only low frequency components to pass is used, the high frequency components of the musical sound signal will be degraded. For these conflicting reasons, conventional interpolation functions have to be determined based on a compromise between noise generation and degradation in the high frequency range and are not optimal for all types of waveform samples. Was.

SUMMARY OF THE INVENTION The present invention has been made to address the above-described problems, and has as its object the purpose of releasing a sound sample from an attack of a musical tone even if a group of waveform samples to be read is changed due to differences in timbre, key touch, pitch, and the like. (1) to provide a tone signal generator which always realizes optimal interpolation of a waveform sample by selectively using an interpolation function corresponding to the change even when a group of waveform samples to be read is changed with the passage of time. It is in.

[0005]

In order to achieve the above object, a first structural feature of the present invention is to select one of a plurality of sets of waveform samples stored in a waveform memory. In a tone signal generating device which is selectively read out by a signal, an interpolation function which defines an interpolation parameter used for interpolation of a waveform sample is selected by the waveform selection signal.

[0006] A second structural feature is that it is stored in a waveform memory and selectively read out by a waveform selection signal.
One of multiple sets of waveform samples
In a musical tone signal generating apparatus configured to read out a series of waveform samples representing musical tone waveforms, the interpolation function is controlled by a control signal that fluctuates according to the waveform selection signal.
That is to choose .

A third structural feature is one of a plurality of sets of waveform samples stored in a waveform memory and selectively read out by a waveform selection signal, and represents a tone waveform having a plurality of cycles. In a tone signal generator for reading a series of waveform samples, the interpolation function is selected by both a waveform selection signal and a time-varying control signal .

[0008]

According to the first feature configured as described above, according to the waveform sample group to be read and the interpolation function,
Since both are selected by the waveform selection signal,
Read out the interpolation parameters used for the group of waveform samples
Can be changed corresponding to the set of waveform samples. Further, according to the second structural feature configured as described above, the reading
The waveform sample group consisting of multiple cycles
Signal and the interpolation function is
Selected by a control signal that fluctuates according to the signal.
When the waveform sample group consisting of multiple cycles
Even if it changes with the passage of time, the waveform
While changing the interpolation parameters used for the sample
Can be changed according to the waveform sample group
You. Further, according to the third feature configured as described above, a group of waveform samples to be read is determined by the waveform selection signal.
The control signal and the interpolation function
And the waveform selection signal,
The output waveform sample group consisting of multiple cycles
Therefore, even if it changes, the read waveform sample group
Do not change the interpolation parameters used for interpolation
However, it can be changed in accordance with the readout waveform sample group.
Wear. Therefore, according to each of these features, it is possible to use the interpolation parameters according to the interpolation function most suitable for each waveform sample group to be read, and the waveform sample group to be read is changed due to differences in timbre, key touch, pitch, etc. However, even if the waveform sample group read out changes over time from the attack of the musical tone to the release,
By selectively using the interpolation function in response to the change, it is possible to always achieve the optimal interpolation of the waveform sample.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the entirety of an electronic musical instrument to which a tone signal generating apparatus according to the present invention is applied.

This electronic musical instrument comprises a keyboard device 11 composed of a plurality of keys for designating the pitch of a musical tone to be generated, and a plurality of tone color selection switches 12 for selecting a tone color of the musical tone to be generated. ing. The keyboard device 11 and the tone selection switch 12 are connected to a microcomputer 13. The computer 13 generates a waveform together with the sound source interface 14 in response to the key press and release of the keyboard device 11 and the operation of the tone selection switch 12. The generation of each tone signal in a plurality of tone generation channels of the device 15 is controlled. Specifically, the microcomputer 13 and the sound source interface 14 have the following functions.

The microcomputer 13 assigns a newly-depressed key to one of a plurality of tone generation channels in response to a key depression on the keyboard device 11, and stores the key corresponding to the assigned channel in the tone generator interface 14. Pitch data NN indicating the pitch of the depressed key and key touch data K indicating the key touch strength of the key in the area
In addition to writing T, a key-on signal KON for instructing the assigned channel to start generating a musical tone is output via the tone generator interface 14. In response to this, the sound source interface 14 converts the stored pitch data NN into a frequency number FNO that increases in proportion to the key pitch frequency, and outputs it to the assigned channel together with the key touch data KT.

In response to the key release from the keyboard device 11, the microcomputer 13 searches for a tone signal generation channel to which the newly released key is assigned.
Key-off signal KOF for instructing the same channel to stop generating a tone through the tone generator interface 14
Is output.

The microcomputer 13 responds to the operation of the timbre selection switch 12 by a timbre number TC representing the timbre designated by the operated timbre selection switch 12.
Is stored.

The microcomputer 13 responds to key depression of the keyboard device 11 and operation of the tone color selection switch 12,
Control parameters WN, AS, LS, LE, P1 to P for controlling the tone and volume of the tone signal based on the tone color number TC, pitch data NN and key touch data KT.
5, FMS, FML, FMDT, EG are calculated and output to the assigned channel via the sound source interface 14. The control parameter WN (hereinafter referred to as a waveform number WN) selects one of a group of waveform samples to be read and output, and the other control parameters AS,
LS, LE, P1 to P5, FMS, FML, FMDT,
The EG will be described later in the description of each circuit using the control parameters.

The sound source interface 14 is connected to a waveform generator 15 and an envelope generator 16 having the same number of time-division channels as the number of tone generation channels. The waveform generator 15 will be described later in detail with reference to FIGS. 2 and 5, but basically corresponds to a key pitch at which a key of a waveform sample group designated by a waveform number WN is depressed for each time division channel. Multiplier 1 at the read speed
7 is output. The envelope generator 16 forms an amplitude envelope waveform signal that rises in response to key depression and attenuates in response to key release for each time-division channel, and outputs it to the multiplier 17. An attack level, an attenuation coefficient, and the like that determine the shape of the amplitude envelope waveform signal are determined by a control parameter EG supplied from the microcomputer 13 via the sound source interface 14.

The multiplier 17 multiplies the waveform sample from the waveform generator 15 by the amplitude envelope waveform signal from the envelope generator for each time-division channel and outputs the result to the accumulator 18. The accumulator 18 accumulates each output signal for each time-division channel and supplies the output signal to the D / A converter 21. The D / A converter 21 converts the accumulated signal into an analog signal and supplies the analog signal to the sound system 22. The sound system 22 includes an amplifier, a speaker, and the like.
A tone corresponding to the converted analog signal is generated. As a result, the tone of the tone specified by the tone selection switch 12 is output from the sound system 22 to the keyboard device 11.
Will be sounded in response to the key press operation at.

Next, the waveform generator 15 of FIG. 1 will be described in detail. FIG. 2 is a block diagram showing details of the waveform generator 15. The generator 15 includes a waveform memory 31. The waveform memory 31 stores a plurality of sets of waveform samples respectively corresponding to a plurality of types of musical tone waveforms, and each waveform sample group is composed of a series and a large number of waveform samples discretely representing a musical tone waveform having a large number of periods. . In order to save data, a large number of waveform samples of each set are divided into an attack portion read only once at the rise of a musical tone and a loop portion repeatedly read thereafter, and an attack of a tone waveform designated by a waveform number WN is performed. Section start address and the loop section start address and end address are control parameters AS (WN) and LS (W
N) and LE (WN).

The waveform memory 31 has an address generator 32
Part (high-order bit) IN of address signal ADR from
A value obtained by adding T and the count value CNT from the interpolation counter 33 by the adder 34 is given as a read address signal. The address generator 32 outputs a key-on signal KON, a frequency number FNO, and a control parameter AS (W
N), LS (WN) and LE (WN) are input, and the frequency number FNO is accumulated in each time division channel for each DAC cycle, and the waveform of the attack portion of the musical sound waveform designated by the waveform number WN The sample is read once in response to the key-on signal KON, and then an address signal ADR for repeatedly reading the waveform sample of the loop portion is formed and output (see FIG. 10). Therefore, the address signal ADR of each time-division channel is a signal that changes at a speed proportional to the frequency number FNO at every predetermined cycle. The interpolation counter 33 outputs an interpolation count value CNT that repeatedly changes from “0” to “5” during each time-division channel timing. As a result, if the integer portion INT of the address signal ADR is only to represent the sample values Y0 tone waveform of FIG. 11, during one time division channel timing, from the waveform memory 31 6 waveform sample value Y ₀ ~Y5 The clock signal φab is read out every one cycle.

The output of the waveform memory 31 is connected to a multiplier 36 via a delay circuit 35. The multiplier 36 converts the waveform sample values Y _{0 to} Y ₅ into an interpolation value supplied from an interpolation coefficient generator 40. Six interpolation coefficients a ₀ to
sequentially multiplying a _5, respectively. Delay circuit 35 is used for each output time alignment of the waveform sample values Y ₀ to Y ₅ and the interpolation coefficients a ₀ ~a _5. The multiplication results are accumulated is supplied to the interpolator accumulator 37, the waveform sample value Y ₀ to Y ₅ using the interpolation coefficients a ₀ ~a ₅ as the accumulator 37 is shown in the following Equation 1 One waveform sample value Y is calculated by interpolation and output.

[0020]

[Number 1] _{Y = a 0 Y 0 + a} 1 Y 1 + a 2 Y 2 + a 3 Y 3 + a 4 Y 4 + a 5 Y 5 interpolation coefficient generator 40 includes an interpolation coefficient memory 41. As shown in FIG. 3, the interpolation coefficient memory 41 includes k (an integer of 2 or more) interpolation coefficient tables. Each interpolation coefficient table is selected by a first interpolation coefficient selection signal FS1 from the function selection unit 42. Each interpolation coefficient table is further divided into eight areas (however, two areas are not used in the present embodiment), and each area has a count value CNT (0 to 5) from the interpolation counter 33.
, Respectively. In each of the six areas, interpolation coefficients a _{0 to} a ₅ addressed by the decimal part (lower bit) FRAC of the address signal ADR from the address generator 32 are stored, respectively.

These interpolation coefficients a _{0 to} a ₅ are, for example, as shown in FIG.
It is well known that a plurality of waveform sample values Y _{0 to} Y ₅ are interpolated by the calculation of the above equation 1 using these interpolation coefficients a _{0 to} a _5. That is. Further, according to the interpolation defined by such an interpolation function, the waveform sample value Y which is the output is
It is well known that an effect equivalent to that obtained by low-pass filter processing is added. Changing the interpolation function from the solid line to the dashed line in FIG. This corresponds to being set low. The k interpolation coefficient tables store interpolation coefficients a _{0 to} a ₅ defined by interpolation functions having different characteristics as described above.

The function selector 42 includes an aperiodic signal generator 51 and a low-frequency oscillator 52 for generating a time-varying control signal, as shown in detail in FIG. The non-periodic signal generator 51 receives the key-on signal KON and the control parameters P1 to P5, and outputs a first control signal FEG that changes temporally and non-periodically from the arrival of the key-on signal KON (for example, see FIG. 6). ). In this case, the control parameter P1 indicates the initial level, and the control parameters P2 to P5
Represents a target level after a predetermined time of the first control signal FEG and a rate of change until the target level is reached, and the aperiodic signal generator 51 uses these control parameters P
The first control signal FEG on the polygonal line is formed using 1 to P5. The low-frequency oscillator 52 receives the key-on signal KON and the control parameters FMS, FML, and FMDT, and outputs a second control signal LFO representing a low-frequency signal whose amplitude gradually increases with time from the arrival of the key-on signal KON ( For example, see FIG. In this case, the control parameter FM
S represents the cycle of the second control signal LFO, the control parameter FML represents the maximum amplitude level of the signal LFO, and the control parameter FMDT represents the delay time from the arrival of the key-on signal KON to the generation of the signal LFO. , The low frequency oscillator 52 controls these control parameters FMS and FM.
The second control signal LFO is formed using L, FMDT.

The first control signal FEG and the second control signal LFO are added by an adder 53, and are limited to a range of "0" to "1" by a limiter 54 and output to a multiplier 55. . The multiplier 55 multiplies the output signal of the limiter 54 by a value TN−1 obtained by subtracting “1” by the subtractor 57 from the number of tables TN output from the first table 56 and outputs the result. As shown in FIG. 8, the first table 56 stores a table number TN corresponding to the waveform number WN, and the table number TN is selectively read out and output based on the waveform number WN. The table number TN represents the number of interpolation coefficient tables (see FIG. 3) used for the interpolation calculation of the waveform sample group specified by the waveform number WN.
Therefore, the output of the multiplier 55 is a signal that continuously changes between “0” and a number smaller by “1” than the number TN of tables used. For example, if the number of tables TN is “4”, the output of the multiplier 55 changes between “0” and “3”.

The integer part (upper bit) INT of the output of the multiplier 55 is passed through an adder 58 to the second table 5.
9 is output. The clock signal φab is supplied to the adder 58 via an inverter 58a.
Is to output the integer part INT as it is when the clock signal φab is at a high level, and to add and output “1” to the integer part INT when the clock signal φab is at a low level. The second table 59 is shown in FIG.
To As, for each waveform number WN, a plurality of table data TD for designating a plurality of interpolation coefficients table used for interpolation of waveform sample group designated by the same number WN (see FIG. 3), respectively I remember. Waveform number W
The number of table data DT for each N is the above table number TN
, And a plurality of table data TD specified by the waveform number WN are specified by the output of the adder 58, and are output from the second table 59 to the first interpolation coefficient selection signal FS.
1 is output.

For example, if the waveform number WN is "1",
TD1 as table data TD in the second table 59
= 2, TD2 = 5, TD3 = 6, TD4 = 0. On the other hand, from the first table 56, the number of tables TN = 4
Is output, and the integer part INT of the output signal of the multiplier 55 represents any one of “0”, “1”, and “2”, so that “0”, “1”, and “1” Signals representing “2”, “2” and “3” are alternately output in synchronization with the clock signal φab. Therefore, the first interpolation coefficient selection signal FS1 from the second table 59 becomes TD1 = 2 according to the first control signal FEG from the aperiodic signal generator 51 and the second control signal LFO from the low frequency oscillator 52. TD2
= 5, TD2 = 5 and TD3 = 6, TD3 = 6 and TD4 =
0 is a signal that alternately represents 0 in synchronization with the clock signal φab. The interpolation coefficients a _{0 to} a ₅ in the interpolation coefficient table designated by the first interpolation coefficient selection signal FS 1 from the interpolation coefficient memory 41 (see FIG. 3) of FIG. Interpolation coefficients a _{0 to} a ₅ addressed by the value CNT and the decimal part FRAC of the address signal ADR are sequentially output two by two in synchronization with the clock signal φab.

The interpolation coefficient memory 41 has a latch circuit 4
3, 44 are connected. The latch circuits 43 and 44 are controlled by a clock signal φab and a signal obtained by inverting the clock signal φab by an inverter 45, and alternately latch the two interpolation coefficients a _{0 to} a ₅ , respectively, to the interpolation coefficient interpolation circuit 46. Output. The interpolation coefficient interpolation circuit 46 is supplied with the decimal part (lower bit) FRAC of the output signal from the multiplier 55 of the function selection unit 42 as the second interpolation coefficient selection signal FS2. The interpolation coefficient interpolation circuit 46
Using the interpolation coefficient selection signal FS2, the latch circuits 43, 4
Each of the pair of interpolation coefficients a _{0 to} a ₅ latched in step 4 is interpolated (for example, the two interpolation coefficients are mixed using the second interpolation coefficient selection signal FS2 as a mixing ratio), and the interpolated interpolation coefficient a _{0 is used.} Ａa ₅ is output to the multiplier 36.

In the embodiment configured as described above,
When any key is depressed on the keyboard device 11, the microcomputer 13 supplies pitch data NN representing the pitch of the depressed key to the sound source interface 14, and the sound source interface 14 outputs the pitch data NN. Is supplied to the address generator 32. At the same time, the microcomputer 13 determines the waveform number WN according to the tone color number TC, the pitch data NN, and the key touch data KT specified by operating the tone color selection switch 12, and determines the waveform number WN according to the waveform number WN. Thus, the control parameters AS, LS, LE are determined and supplied to the address generator 32. The address generator 32 designates a waveform sample belonging to a waveform sample group selected by the control parameters AS (WN), LS (WN), LE (WN), and changes at a speed proportional to the frequency number FNO. An address signal ADR consisting of bits is generated. Therefore, the waveform selection signal of the present invention corresponds to the tone color number TC, the pitch data NN, the key touch data KT, the waveform number WN, and the like.

The interpolation counter 33 outputs a count value CNT that repeatedly changes from "0" to "5" to an adder 34. The adder 34 converts the integer part INT of the address signal ADR and the count value CNT. Addition and waveform memory 3
1 from the memory 31, the integer part IN
Waveform sample value Y ₀ and the next five waveform sample values Y ₁ to Y ₅ are designated is read out as an interpolated waveform sample by T. Therefore, the reading means of the present invention corresponds to the interpolation counter 33 and the adder 34.

In the function selecting section 42, the aperiodic signal generator 51 (the control signal generating means of the present invention) determines the tone color number TC, the pitch data NN and the key touch data KT in response to the key depression. Control parameters P1 to P
5, the low-frequency oscillator 52 (the control signal generating means of the present invention) is determined by the timbre number TC, the pitch data NN, and the key touch data KT. Control parameters FMS, F
A second control signal LFO corresponding to ML and FMDT is generated. On the other hand, the function selection section 42 stores the tone number T
C, the pitch number data NN, and the waveform number WN determined by the key touch data KT are also supplied, and the interpolation coefficient is obtained by the operation of the multiplier 55, the first table 56, the second table 59, and the like in the selector 42. The interpolation coefficients a _{0 to} a ₅ as the interpolation parameters of the present invention are supplied from the memory 41 to the multiplier 36 via the latch circuits 43 and 44 and the interpolation coefficient interpolation circuit 46. Then, by the action of the multiplier 36 and the interpolator accumulator 37, the waveform sample value Y ₀ to Y ₅ by using the interpolation coefficients a ₀ ~a ₅ is outputted as a waveform sample value Y is interpolated. Therefore, the multiplier 55, the first table 56, the second table 59, the interpolation coefficient memory 41,
The interpolation coefficient interpolation circuit 46 and the like constitute the interpolation parameter generation means of the present invention, and the multiplier 36 and the interpolation accumulator 37 constitute the interpolation means of the present invention.

As can be understood from the above description of operation, according to the above embodiment, the waveform sample group selected by the waveform selection signal including the tone color number TC, the pitch data NN, the key touch data KT, the waveform number WN, etc. Accordingly, interpolation coefficients a _{0 to} a ₅ as interpolation parameters used for interpolation of the waveform samples belonging to the same waveform sample group are changed. In addition, since the first control signal FEG changes with the lapse of time in response to the reading of the waveform sample group representing the musical tone waveform for a plurality of cycles with the lapse of time, the first control signal FEG changes with the lapse of time. Correspondingly, an interpolation coefficient a ₀ as an interpolation parameter used for interpolation of waveform samples belonging to the same waveform sample group.
a ₅ is also changed. Therefore, the interpolation coefficients a ₀ to a ₀ according to the optimum interpolation function for each waveform sample group to be read out.
and available a _5, tone, key touch, even after changing the waveform sample group to be read out by the difference in such pitches, also waveform sample group to be read out according to reach over time the release from the attack of the tone is changed However, it is possible to realize the optimal interpolation of the waveform sample corresponding to the change. The second control signal LFO is also acts to vary the interpolation coefficient a ₀ ~a ₅ periodically, the periodic change in tone is also realized.

In the above-described embodiment, a plurality of types of waveform samples representing a time-varying musical tone waveform composed of a large number of periods are stored in the waveform memory 31. The present invention can also be applied to a musical tone signal generator in which a plurality of types of waveform samples representing musical tone waveforms are stored in the waveform memory 31. In this case, the address generator 32 is configured to generate the address signal ADR for repeatedly reading the waveform sample group, and the aperiodic signal generator 51 and the low-frequency oscillator 52 are omitted, and the address generator 32 simply responds to the waveform number WN. And interpolation coefficients a _{0 to} a ₅
May be determined.

Further, in the above embodiment has been configured to interpolate six interpolated waveform sample values Y ₀ to Y _5, the number of the interpolated waveform sample values is not limited to six , Or another number. Further, the number of the interpolation waveform sample values may be selectively set in connection with connection to another circuit (for example, a digital filter), switching of the number of tone signal generation channels, and the like. In this case, the maximum value of the counter value CNT of the interpolation counter 33 is changed, and the channel timing and the like are changed accordingly.

Further, in the above embodiment, the waveform number WN is determined according to the tone color number TC, the pitch data NN and the key touch data KT, and the interpolation coefficients a _{0 to} a ₅ are defined according to the same number WN. Although the interpolation function to be performed is determined, the interpolation function and the interpolation coefficients a _{0 to} a ₅ whose cut-off frequency decreases as the frequency number FNO further increases are determined. It is possible to more effectively remove aliasing noise included in the musical tone waveform signal to be reproduced.

[Brief description of the drawings]

FIG. 1 is a schematic block diagram showing an entire electronic musical instrument to which a tone signal generating device according to the present invention is applied.

FIG. 2 is a detailed block diagram of the waveform generator of FIG.

FIG. 3 is a memory map of an interpolation coefficient memory of FIG. 2;

FIG. 4 is a graph showing an interpolation function that defines an interpolation coefficient stored in the interpolation coefficient memory.

FIG. 5 is a detailed block diagram of a function selection unit in FIG. 2;

FIG. 6 is a diagram showing a first example of a signal output from the aperiodic signal generator of FIG.
5 is a time chart illustrating an example of a control signal.

FIG. 7 is a time chart showing an example of a second control signal output from the low frequency oscillator of FIG.

FIG. 8 is a table map of the first table in FIG. 5;

FIG. 9 is a table map of a second table in FIG. 5;

FIG. 10 is a time chart for explaining the circuit operation of FIGS. 2 and 5;

FIG. 11 is a time chart for explaining the interpolation operation of FIG. 2;

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 11 ... Keyboard apparatus, 12 ... Tone selection switch, 13 ... Microcomputer, 15 ... Waveform generator, 16 ... Envelope generator, 22 ... Sound system, 31 ... Waveform memory, 32 ... Address generator, 33 ... Interpolation counter, 36
... multiplier, 37 ... interpolation accumulator, 40 ... interpolation coefficient generator,
41: interpolation coefficient memory, 42: function selection unit, 43, 44
... Latch circuit, 46 ... Interpolation coefficient interpolation circuit, 51 ... Aperiodic signal generator, 52 ... Low frequency oscillator, 56 ... First table, 59 ... Second table.

Claims (3)

(57) [Claims] 1. A waveform memory which stores a plurality of sets of a series of waveform samples discretely representing musical tone waveforms corresponding to a plurality of types of tone waveforms, and selects one of the plurality of sets of waveform sample groups. Inputting a waveform selection signal and a pitch designation signal for designating a pitch, designating waveform samples belonging to a waveform sample group selected by the inputted waveform selection signal, and inputting the pitch designation signal Address signal generating means for generating an address signal consisting of a plurality of bits that changes at a speed corresponding to the pitch specified by the following: and interpolating a plurality of waveform samples near one waveform sample specified by the upper bits of the address signal Reading means for reading as a waveform sample for use in accordance with an interpolation function selected by the waveform selection signal and using lower bits of the address signal. Interpolation parameter generating means for outputting an interpolation parameter that changes according to the value represented; interpolation for deriving one waveform sample by interpolating the read interpolation waveform sample using the output interpolation parameter Music signal generating device comprising: 2. A series of waveform samples that discretely represent a musical tone waveform having a plurality of periods corresponding to a plurality of types of musical tone waveforms.
Waves for selecting the waveform memory storing a plurality of sets each one of said plurality of sets of waveform sample group
A waveform selected by the input waveform selection signal by inputting a shape selection signal and a pitch designation signal for designating the pitch
Address signal generating means for generating an address signal consisting of multiple bits that will change at a speed corresponding to the tone pitch designated by the sample pitch designation signal the specified vital input waveform samples belonging to the group, the address signal Reading means for reading, as interpolation waveform samples, a plurality of waveform samples near the waveform sample specified by the upper bits of the control signal; control signal generating means for generating a control signal that fluctuates according to the waveform selection signal; Interpolation parameter generating means for outputting an interpolation parameter that changes according to a value represented by a lower bit of the address signal in accordance with an interpolation function selected by the following; and the read-out using the output interpolation parameter Interpolating means for interpolating an interpolation waveform sample to derive one waveform sample No. generator. 3. A waveform memory storing a plurality of sets of a series of waveform samples discretely representing a musical tone waveform having a plurality of periods corresponding to a plurality of types of musical tone waveforms, and one of the plurality of waveform sample groups. Inputting a waveform selection signal for selecting a pitch and a pitch specification signal for specifying a pitch, specifying waveform samples belonging to a waveform sample group selected by the input waveform selection signal, and specifying the input sound. Address signal generating means for generating an address signal composed of a plurality of bits that change at a speed corresponding to a pitch specified by a high specifying signal; and a plurality of waveforms near one waveform sample specified by upper bits of the address signal Reading means for reading out a sample as an interpolation waveform sample; control signal generating means for generating a time-varying control signal; the waveform selection signal and the control signal An interpolation parameter generating means for outputting an interpolation parameter that changes according to a value represented by a lower bit of the address signal in accordance with an interpolation function selected by a signal, and the read-out using the output interpolation parameter. Interpolating means for interpolating the interpolated waveform sample to derive one waveform sample.