JPH0460695A - Musical sound waveform generator - Google Patents

Abstract

PURPOSE:To synthesize musical sound having various harmonic characteristics by switching the PCM waveform signal from a PCM waveform signal generating means and a normal waveform signal from a normal waveform signal generating means with respect to time as the signal to be given to a modulated musical sound signal generating means to obtain a modulation signal after the start of sound production. CONSTITUTION:After the sound production start indication, for example, the attack part or the attack part and the release part of musical sounds give the PCM waveform signal from the PCM waveform signal generating means as the modulation signal to the modulated musical sound signal generating means to generate the modulated musical sound signal. The other parts like the sustain part and the decay part give the normal waveform signal from the normal waveform signal generating means as the modulation signal to the modulated musical sound signal generating means to generate the modulated musical sound signal. Thus, the musical sounds having very distinct and complicated characteristics are produced, for example, in the attack part, the release part, etc.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a musical sound waveform generator for an electronic musical instrument,
More specifically, the present invention relates to a musical sound waveform control device that can generate musical sound waveforms having various overtone characteristics depending on a modulation method.

[Conventional technology]

The sound played by musical instruments has a complex harmonic structure, with the frequency and amplitude of overtones constantly changing, and some instruments include harmonics of non-integer orders.Also, each musical instrument has a unique noise component, such as the attack (rise) of a piano. It has an impulsive noise, etc.

These overtones and noise components greatly characterize the timbre of those instruments.

In order to realistically reproduce such musical sounds with electronic instruments,
In addition, in order to create a new sense of sound that did not exist before,
Various tone synthesis methods are used in electronic musical instruments.

That is, there are many musical tone synthesis methods, such as the PCM method, the frequency modulation method, the phase modulation method, and the overtone addition method, each of which has its own advantages and disadvantages. By appropriately combining them, the above objectives can be achieved to some extent. For example, during the attack of a musical tone, in addition to the impulsive noise mentioned above, the fundamental tone and overtones fluctuate in a complex manner, so the P
The CM method is suitable, but the PCM method requires a memory with a large storage capacity for the portion after sustain (stationary portion), and it may be possible to switch to another method from the viewpoint of cost.

As an example, in JP-A-58-102296, musical tones are synthesized using the PCM method for the musical sound waveform at the time of attack, and the FM method for the subsequent stages.

This will be explained below.

Now, when a key is pressed, numerical data corresponding to the pitch of the pressed key is repeatedly accumulated to obtain an accumulated value that changes at a speed corresponding to the pitch. Thereafter, the waveform data of the original musical instrument of the attack section is read from the PCM waveform memory using this accumulated value, and the envelope of the attack section shown in FIG. 14(a) is given to it.

On the other hand, the numerical data corresponding to the pitch of the pressed key, the accumulated value that changes at a speed corresponding to the pitch by repeatedly accumulating the numerical data, and another constant constant are used as the tone of the FM method. A frequency modulated waveform is obtained by manually inputting the generator.

After that, the envelope shown in Figure 14 (G) is given to that waveform, and the adder adds and synthesizes it with the musical sound waveform based on the PCM method described above, resulting in the attack, sustain, and release of the musical sound as shown in Figure 14 (C). All waveform signals of one musical tone having a (damping) section are synthesized.

As is clear from the above, this musical tone synthesis method uses the PCM method for the attack part of the musical tone, and the FM method after that.
This method changes the tone synthesis method depending on the time elapsed from the attack.

Next, two conventional examples regarding the above-mentioned FM system will be explained.

As the first conventional example of the FM system, the
There are electronic musical instruments based on the FM system described in Japanese Patent Application Laid-Open No. 50-126406 and the like. This method is basically e = A −5in (ωct+I(t) sin ω
mt) ... The waveform output e obtained by the calculation formula (1) is a musical sound waveform, and the carrier wave frequency ω.

and the modulation wave frequency ω for modulating it are selected in an appropriate ratio, a modulation depth function 1(t) that can change over time is set, and an amplitude coefficient A that can also change over time is set. By setting , it is possible to synthesize musical tones that have complex overtone characteristics and whose overtone characteristics can change over time. In addition to synthesizing musical tones that are close to the musical tones of actual instruments, it is also possible to synthesize musical tones that have complex overtone characteristics and whose overtone characteristics can change over time. It is also possible to obtain unique synthesized sounds.

Furthermore, as a second conventional system that is an improvement on the FM system, there is an electronic musical instrument described in Japanese Patent Publication No. 12279/1983. This method uses triangular wave operation instead of the sine operation in equation (1), and e=A−T (α+I(t) T (θ)) ・・−
The waveform output e obtained by the arithmetic expression (2) is used as a musical sound waveform. Here, T(θ) is a triangular wave function generated by the carrier phase angle θ.

Then, by advancing the carrier wave phase angle α and the modulating wave phase angle θ at an appropriate speed ratio, and setting the modulation depth function I(t) and amplitude coefficient A in the same manner as in the first conventional example, musical tones can be produced. Waveforms can be synthesized.

[Problem to be solved by the invention]

Based on the above equation (1), <In the first conventional example of the FM method,
A sine wave sinωmt is used as a modulation signal for modulation. In addition, in the second conventional example of the <FM method based on (2) 2, a triangular wave of T(θ) is used. In this way, conventional FM systems use only a constant p-function waveform as a modulation signal, which limits the characteristics of musical tones that can be generated.
Even if this conventional example is applied to the above-mentioned method of synthesizing musical tones by switching between the PCM method and the FM method, there is a problem in that the desired musical tone cannot be obtained.

An object of the present invention is to make it possible to freely generate a synthesis of musical tones having a wide variety of overtone characteristics.

[Means to solve the problem]

The present invention first includes modulated musical tone signal generating means for generating a modulated musical tone signal by converting a mixed output obtained by mixing a modulating signal with a carrier signal based on a predetermined functional relationship. As the means, sound sources of various modulation methods such as frequency modulation and phase modulation can be used.

Next, a PC that generates a PCM waveform signal according to the PCM method.
It has M waveform signal generation means.

Here, the term PCM method in the present invention refers to all waveform readout methods (waveform encoding methods) such as normal PCM method, DPCM method, ADPCM method, zero cross method, ΔM method, etc., and does not refer to normal PCM method. It is not limited to only one method.

Further, a normal waveform signal generation means for generating a normal waveform signal other than the PCM method, furthermore, after the instruction to start sound generation, the PCM waveform signal from the PCM waveform signal generation means is sent to the modulated musical tone signal generation means;
It has a control means for temporally switching the normal waveform signal from the normal waveform signal generating means and applying it as a modulation signal to generate a modulated musical tone signal. For example, when musical tone synthesis is performed by time-division processing for each of a plurality of sound generation channels, the modulated musical tone signal generation means is assigned to a predetermined sound generation channel, and the normal waveform signal generation means is replaced by the modulated musical tone signal generation means itself. If the PCM waveform signal generation means is assigned to another sound generation channel and a sound generation start instruction is given to the sound generation channel to which the modulated musical tone signal generation means is assigned, one sound generation period after the sound generation start instruction is issued. Either input the modulated musical tone signal of the previous own sound generation channel as a normal waveform signal, or use the PC of another sound generation channel one sound cycle before.
This means switches whether the M waveform signal is used as a modulation input or not, and operates the modulated musical tone signal generating means in that sound generation channel.

[For production]

After the instruction to start sound generation, the control means, for example, the attack part or the attack part and the release part of the musical tone supplies the PCM waveform signal from the PCM waveform signal generation means to the modulated musical tone signal generation means as a modulation signal, and generates the modulated musical tone signal. to occur. In other parts, such as the sustain section and the decay section, the normal waveform signal from the normal waveform signal generating means is applied as a modulation signal to the modulated musical tone signal generating means to generate a modulated musical tone signal. This makes it possible to generate musical tones with very distinctive and complex characteristics, for example, in the attack section, release section, etc.

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the drawings.

This embodiment is a musical sound waveform generating device that combines a PCM method and a modulation method for generating musical sound waveforms, and in particular, uses a method different from the conventional FM method as the modulation method. Therefore, before explaining the specific configuration of this embodiment, first, a tone waveform generation method using a modulation method used in this embodiment will be explained.

FIG. 1 is a block diagram of an embodiment of a tone waveform generator using a modulation method which is the basis of the present invention.

The carrier wave phase angle ωet whose value sequentially increases linearly between 0 and 2π (rad) is used as the address of the carrier wave ROMI 01 to read out the carrier signal Wc.

Here, the carrier wave phase angle ωcl is the angular velocity ωc jrad/
5ec) multiplied by time t (sec),
From now on, unless otherwise specified, "," will be collectively expressed as a subscript.

The carrier signal Wc is transmitted to an adder (hereinafter referred to as ADD) 1
At 02, it is added to the modulation signal wM input from the outside, and the sum, waveform Wc+W (rad) is further added to the decoder 1.
03 to obtain a decoded output.

The modulated signal WM and the carrier signal wC are added by an adder (hereinafter referred to as ADD) 102, and the added waveform WC
+WM (rad) is further decoded by a decoder 103 to obtain a decoded output.

Then, the decoded output is MUL 104 with amplitude coefficient A
The final waveform output e is obtained.

In the musical sound waveform generator having the above configuration, first, the carrier wave R
The function waveform shown in FIG. 2 is stored in OMl0I. Now, let π be the constant of pi, and the carrier wave phase angle ωct [rad) and the carrier signal WC (r
ad ), respectively, Wc = (π/2)si
n ω, (... (Region I: 0≦ωcl≦π/2) Wc = tt
−(π/2) sin ωct・・(Area ■: π/2
≦ωct≦3π/2) Wc −2π+ (π/2)si
n ωcl・・ (Region ■: 3π/2≦ωCt≦2π
)・・・・(3)

The carrier signal Wc calculated by the above equation (3) and the modulated signal WM from the outside are added and inputted to the decoder 103, so that the decoder 103 outputs a decoded output, which is further added to the amplitude coefficient A by the MUL 104. The waveform output e after being multiplied is: e = A-TRI ((x/2) sin ωct
+WM)... (0≦ω,≦π/2) e=A-TRI (π-(yr/2) sin (L)
CL+WM) ・ ・ (π/2≦ω, ≦3π/2) ・ ・(4) However, TRI(x) is defined as a triangular wave function.

Here, first, when the modulation signal WM is 0, that is, there is no modulation, the input waveform to the decoder 103 becomes the carrier signal WC itself determined by the above equation (3). That is, e=A-TRI (Wc)...
- (5). Note that the carrier signal Wc and the carrier wave phase angle ω
.

is shown by the relationship A in FIG. 3 based on the above equation (3) or FIG. 2.

On the other hand, the triangular wave function D calculated in the decoder 103
=TRI(x) (where X is the input) is... (T+
lj"l1ll: 3 π/'1sxs'1tt
), and is a function shown in relation B in FIG.

As can be seen from relationship A and relationship B in FIG.
The triangular wave function RI(χ) calculated in 03 is a monotonically increasing function in each region I, ■, and ■ defined by the above equation (3) or (6) 2, and therefore, the above ( The carrier wave phase angle ω, which is the input in equation 3), and the above (6)
Since the input X in the formula always takes a value in the same interval, the above formulas (3), (5), and (6) can be combined in the same interval. That is, the above formula (3) and (6
) is substituted into the above equation (5), we get... (7). That is, when no modulation is performed, a single sine wave A-sin ωct containing no higher-order harmonics is output for any region of the carrier phase angle ω.

That is, if the amplitude coefficient A=1, for example, the relationship between the carrier wave phase angle ωct and the waveform output e when no modulation is performed becomes a single sine wave as shown in the relationship C in FIG. 3.

From the above relationship, in order to realize the process in which a musical tone attenuates into only a single sine wave component, or the generation of a musical tone consisting only of a single sine wave component, it is necessary to input external changes.
It can be seen that it is sufficient to bring the modulation signal WM closer to 0 over time.

Next, the waveform output e when the mixing ratio of the modulated signal WM mixed with the carrier signal Wc is increased in the ADD 102
Think about changes in When the above-mentioned mixing ratio is gradually increased from the value O, the modulation signal WM component is gradually superimposed from the carrier signal Wc only component to the addition waveform w, 10W output from the ADD 102 in FIG. As a result, the waveform output e gradually becomes distorted on the time axis from a single sine wave, and changes to include many high-order harmonic components on the frequency axis. In this case, the conversion function in the decoder 103 originally contains many high-order harmonic components.
Since it is a triangular wave as shown in , if this is further modulated, the frequency characteristics will contain abundant high-order harmonic components of 10 harmonics or higher, making it possible to obtain complex harmonic characteristics according to the modulation signal WM. There is. Moreover, the power of the low-order harmonic components is not simply increased or decreased, but it is possible to obtain complex harmonic changes in response to changes in the mixing ratio. Based on the above (1) 2 explained in the prior art section, in the <FM method 2,
Although it is difficult to express high-order harmonic components of the 11th harmonic or higher, in this embodiment, it is possible to express high-order harmonic components up to around the 30th harmonic.

Based on the above facts, by changing the value of the modulation signal WM in basic module 1 in Figure 1, the musical tone will attenuate into only a single sine wave component, as in the case of an actual musical tone. It is possible to generate musical tones consisting only of process or single sine wave components, and it is also possible to easily generate musical tones in which even high-order overtone components clearly exist as frequency components. In particular, when synthesizing musical tones with low pitches, that is, when synthesizing musical tones whose fundamental frequency (pitch frequency) is low and can contain many high-order harmonics in the audible frequency range, for example, piano When a bass key is played strongly, the attenuated sound of dozens of pillars contains rich harmonics of the 30th order and higher, but when synthesizing such sounds, the musical waveform generation shown in Figure 1 is difficult. The device is very effective.

In the above musical waveform light and production equipment, the above equation (6) or the third
For the decoder No. 103 having the characteristics shown in the relationship B in the figure, the carrier signal Wc is such that the waveform output e becomes a sine wave, or the carrier signal Wc as shown in the equation (3) or the relationship A in FIG. 2 or 3. By storing in the carrier wave ROMl0I,
Although the generation of a single sine wave is not limited to this, the decoder 103 performs an operation on a function that originally contains harmonic components other than a single sine wave, and the decoding A similar effect can be obtained by storing a function whose output becomes a sine wave in the carrier wave ROMI O1. FIGS. 4(a) to 4(d) show examples of combinations of functions calculated by the decoder 4 and functions stored in the carrier ROM10I. In the figure, carrier phase angle ω. , and the carrier signal W, is the carrier wave R
A function stored in OM10I and relating input X and decoded output is calculated by decoder 103. As a result, when the modulation signal WMO value is O, the carrier wave ROM
By inputting the carrier signal Wc output from L0I as input X to the decoder 103, a single sine wave can be output as the waveform output e. Furthermore, by using the functions of the decoder 103 as shown in FIGS. 4(a) to 4(d), if the value of the modulation depth function I (t) is set to a value other than 0, the waveform output e containing many It becomes possible to obtain.

In a specific embodiment of the present invention to be described later in which the basic configuration is the above-described musical waveform generator, the waveform output e of one sampling period before or the musical waveform by PCM is used as the modulation signal WM.
By inputting the signal to the ADD 102 and inputting the signal to the decoder 103, it is possible to synthesize a musical sound waveform containing many higher-order harmonics.

Next, specific embodiments of an electronic musical instrument according to the present invention based on the principle of the musical sound waveform generator described above will be described.

FIG. 5 is an overall configuration diagram of an electronic keyboard instrument according to the present invention realized as a keyboard instrument. This embodiment is based on the configuration of the musical sound waveform generator shown in FIG.
Although the musical tone signal generation circuit according to the present invention is also used, the following explanation will be made with reference to FIG. 1 and the like at any time.

This embodiment is a 32-polyphonic musical tone generator, and each internal circuit operates in 32 time divisions for each sampling period.

The controller 501 includes a switch section 5 (not particularly shown).
18 and the key code KC and velocity VL input from the keyboard section 517,
Carrier frequency CF and envelope information ED, FA,
Generates and outputs a PCM start address A sp and a transport start address ASM. In addition, the controller 50
1 are selectors 505 and 510, 508 and 5, which will be described later.
Selector control signals So, S for controlling opening and closing of 12
t and S2, and further includes a phase data generation section 502,
Each clock φ11φ2, φSl, φs2 for controlling the envelope generator 513, accumulator 516, etc.
, φ, and outputs φR, CT, and pan control data PAN.

Based on the carrier frequency CF set by the controller 501, the phase data generation section 502 generates phase data PH that increases sequentially by the step width of the frequency, and sends it to the carrier address generation section 503 and the PCMC address generation section 04. supply

The transport address generating section 503 outputs data from the waveform ROM 506 via the terminal B of the selector 505 based on the phase data PH.
carrier address ωC to access the carrier signal area of
Generate T(M). In this case, the starting address is
Transport start address A5 from controller 501
Specified by M.

The PCMC address generation 04 is generated from the waveform ROM 50 via the terminal A of the selector 505 based on the phase data PH.
A PCM address ωct(P) for accessing the PCM signal area No. 6 is generated. The start address in this case is specified by the PCM start addresses A and p from the controller 501.

The selector 505 selects either the PCM address ωCT(p) input to the terminal A or the transport address ωCT(M) input to the terminal B based on the selector control signal S0.

When the carrier signal area is accessed by the carrier address ωCT(M), the waveform ROM 506 outputs the corresponding carrier signal Wc to the adder (ADD, hereinafter the same) 507. When the PCM signal area is accessed by the PCM address ωcy(P), the corresponding PCM signal O
F is output and supplied to terminal A of selector 510.

The ADD 507 outputs a delay output or D input to the carrier signal Wc as a modulation signal WH via a selector 508.
−1 is added to output a sum waveform Wc+WM, which is supplied to the triangular wave decoder 509. The selector 508 selects either the delay output input to the terminal A or the delay output 1)-1 input to the terminal B in accordance with the selector control signal S1 from the controller 501.

The triangular wave decoder 509 converts the addition waveform Wc+WM according to the triangular wave function, outputs a decoded output OM, and supplies it to the terminal B of the selector 510. This circuit configuration will be described later.

The selector 510 selects the PCM signal O1 input to the terminal A or the decode output ON input to the terminal B based on the selector control signal S0, and supplies the selected signal to a multiplier (MUL, hereinafter the same) 511.

The MUL 511 is a multiplier for adding an envelope to the PCM signal OF or the decoded output O. The MUL 511 is a multiplier for adding an envelope to the PCM signal OF or the decoded output O.
or the PCM signal corresponding to PCM signal O1 by multiplying either modulated signal D-1 from latch 515.
The waveform output statement outputs a modulated waveform output eM corresponding to the decoded output OM. The selector 512 selects the envelope signal E input to the terminal A or the delay output D-1 input to the terminal B according to the selector control signal S2 from the controller 501. Correspondingly, the envelope generator 513 controls the controller 50 when the key is pressed.
Address data FA and setting data E output from 1
Based on D, an envelope signal E is output. The envelope signal E reaches the initial level IL at the actuation time AT after the key is pressed, then reaches the sustain level SL at the decay time DT, maintains that level until the key is released, and reaches the release time after the key is released. It has a characteristic that it goes to O level at RT time and mutes the sound. Then, each data value of attack time AT, initial level IL, decay time DT, sustain level SL, and release time RT at this time is set as setting data ED by controller 501 at the start of key depression. Each data is identified by address data FA.

Next, FIG. 6 shows an embodiment of the triangular wave decoder 509 shown in FIG. In the same figure, 11-bit inputs AO to AIO
corresponds to the addition waveform WC+WM in FIG. 5, and the 10-bit outputs BO to B9 correspond to the decoded output OM in FIG.

Addition waveforms A9 and AIO of the 10th bit and most significant bit from the adder 508 in FIG.
input to each first input terminal of the EOR 601. Also,
Each second input terminal of EOR601 #0 to #8 has 0 to
An 8-bit addition waveform AO-A8 is input.

Each output of the EOR601 of #0 to #8 above is used as the decode output BO to B8, and the addition waveform AI of the most significant bit
O is the decode output of the most significant bit representing the sign bit B9
is output to multiplier 510 in FIG.

The operation of the above embodiment will be explained below.

Now, assuming that the value Z determined by the addition waveforms AO to AIO increases sequentially in direct proportion to the passage of time, the addition waveforms AO to AIO
One period in the full range of O~2π (rad)
Suppose that we can specify the phase angle of . In the first case, the logical combination (A10, A9) of the most significant bit AIO of the addition waveform and the 10-bit bar A9 is (0,0).
In this case, the value indicated by the addition waveforms AO to AIO is 1/4 of the full range from O, that is, π/2 (rad)
This is a case where it changes up to. In this range, the output of the EOR 601 of #9 is logic 0. Therefore, as the addition waveforms AO to A8 input to the EOR 601 of #0 to #8 increase sequentially as time passes, the waveforms exactly similar to it will become lower. It appears as 9-bit decoded outputs BO to B8.

Furthermore, the decoded output B of the most significant bit which is the sign bit
9 is a logical O, which is equal to the most significant bit addition waveform AIO, and therefore produces a positive decoded output in the above range. Expressing this in a formula, if the value determined by the decoded outputs BO to B9 is W, then W=Z However, (0≦2≦π/2)...
(8) becomes.

In the second case, when (Aid, A9) = (0, 1), the value indicated by the addition waveform AO-AIO is π/2
This is a case where the value changes up to π (rad). In this range, the output of #9 EOR 601 is logic 1, so as the addition waveforms AO to A8 input to #0 to #8 (7) EOR 601 increase sequentially over time, the relationship is completely reversed. Waveforms that decrease sequentially are output as decoded outputs BO to B8 of the lower 9 bits. Furthermore, the decode output B9 of the most significant bit, which is the sign bit, is equal to the addition waveform AIO of the most significant bit, which is logic 0, and therefore generates a positive decode output in the above range.

Expressing this in the formula, becomes.

In the third case, when (A10, A9) = (1, 0), the value indicated by the addition waveform AO-AIO is π-3
This is a case where it changes up to π/2 (rad).

In this range, the output of the EOR 601 of #9 becomes logic 1 as in the second case, so the EOR of #0 to #8
The state of OR601 is also the same as in the second case, and as the input addition waveforms AO to A8 increase sequentially over time, the waveforms that decrease sequentially in a completely opposite relationship become lower 9.
It is output as a bit decode output BO-88. On the other hand, decode output B9 of the most significant bit which is the sign bit
generates a negative decoded output in the above range because the addition waveform AIO of the most significant bit has changed to logic 1.

Expressing this in a formula, W=-Z+π However, (π≦Z≦3π/2) ・00).

In the fourth case, when (A10, A9) = (1, 1), the value indicated by the addition waveform AO-AIO is 3π/
This is a case where it changes from 2 to 2π (rad).

In this range, the output of the EOR 601 of #9 becomes logic O as in the first case, so the EOR of #0 to #8
The state of the OR 601 is also the same as in the first case, and as the input addition waveforms AO to A8 increase sequentially over time, waveforms exactly the same are output as the decoded outputs BO to B8 of the lower 9 bits. On the other hand, since the addition waveform AIO of the most significant bit is logic 1, the decoded output B9 of the most significant bit, which is the sign bit, generates a negative decoded output in the above range. Expressing this in the formula, W=Z−2π However, (3π/2≦Z≦2π) ・ ・ ・(10
becomes.

To summarize the equations (8) to OD corresponding to the first to fourth cases above, W=Z, (0≦Z≦π/2) W=−Z1π, however, (π/2≦2 ≦3π/2) W=Z−2π However, (3π/2≦Z≦2π) ・ ・ ・0.

Here, if we modify (7) 2 already shown as the characteristic of the decoder 103 in FIG. 1, D= (2/π)X... (0≦X≦π/2) D= (2/π )(-X1π) ... (π/2≦X≦3π/2) D= (2/π) (x -2π) ... (3π/2≦X≦2π) ...θ3) . Comparing the above equation 03) and the above θ equation, the input/output relationship is essentially the same, with only a difference of 2/π in the overall gain. It can be seen that the triangular wave decoder 509 in FIG. 5 operates in exactly the same way as the decoder 103 in FIG. 1, which is shown by the characteristic of equation (7) above.

In the configuration up to this point, when each terminal A of the selectors 505 and 510 is selected by the selector control signal S0 output from the controller 501, musical tone synthesis using the PCM method is performed. That is, the phase data generation section 50
2, the carrier frequency C from the controller 501
Phase data PH as shown in FIG. 8(a) is generated at a repetition period corresponding to F. And this phase data PH
, the PCM address ω as shown in FIG. 8(b) is determined by the PCM start address AsP from the controller 501.
ct(P) is generated. In this example, the PCM start address A sp is 1500H (H represents a hexadecimal number). As a result, the waveform RO illustrated in FIG.
PC number 41 in order from 7F less 1500H of M506
The M signal signal furnace 18 is read out as shown in Figure (C).

Then, the MtJL 511 adds an envelope to the PCM signal OP, thereby performing musical tone synthesis using the PCM method.

-4. When each terminal B of the selectors 505 and 510 is selected by the selector control signal S0 output from the controller 501, musical tone synthesis is performed using the modulation method shown in FIG. That is, the phase data generating section 502 generates phase data PH as shown in FIG. 9(a) at a repetition period corresponding to the carrier frequency CF from the controller 501. Then, using this phase data PH and the transport start address ASH from the controller 501,
A transport address ω as shown in FIG. 9(b). , (M) are generated. In this example, the transport start address As, I is ooo.

It is H. As a result, the waveform ROM illustrated in FIG.
Starting from address 0OOOH of 506, the carrier signal Wc having the characteristics shown in FIG. 2 is repeatedly read out as shown in FIG. 9(C). In this case, the waveform ROM 506 corresponds to the carrier wave ROM10I in FIG. 1, and the ADD 507 corresponds to the carrier wave ROM10I in FIG.
D 105, the triangular wave decoder 509 corresponds to the decoder 103 in FIG. 1, and the MUL 511 corresponds to the MU in FIG.
The configuration corresponds to L104, and musical tone synthesis using the modulation method described in FIG. 1 is performed.

Here, the entire circuit of this embodiment shown in FIG.
It is possible to generate 32 tones in parallel based on key press operations, and for this reason, the present embodiment operates in 32 time divisions for each sampling period, which is one musical tone generation period. That is, the phase data generation section 502 has a built-in register that holds the carrier frequency CF for 32 sound generation channels, and a 32-stage shift register that holds accumulated values for each sound generation channel based on the register, although not particularly shown in the figure. According to the clocks φ and φ2 output from the controller 501,
The accumulation operation is performed independently for each sound generation channel, and the phase data PH as shown in FIG. 8(a) or FIG. Output. Similarly, the envelope generator 513 has a built-in register that holds address data FA and setting data ED for 32 sound generation channels, and a 32-stage shift register that holds envelope values for each sound generation timing (sampling period) based on the register. Clock φ1, φ output from controller 501
2, an independent envelope signal E is output for each sound generation channel. Also, PCMC address generation 04
There is also a register that holds the PCM start address ASP for 32 sound generation channels, and the cumulative value of the PCM address ωct (P) for each sound generation timing based on the register (see Fig. 8).
It has a built-in 32-stage shift register that holds the PCM address ω for each sound channel.
Generate CT(P). Furthermore, a transport address generation section 50
3 divides the phase data PH for each sound generation channel by a predetermined coefficient and sets the transport start address AS fixed to this.
The circuit is configured as a circuit that repeatedly reads out the transport address ωCT(M) as shown in FIG. 9(b) for each sound generation channel as data obtained by adding M.

Then, each time a single key press operation is performed on the keyboard section 517, the controller 501 assigns the key press operation to one of the 32 sound generation channels, and sets the corresponding carrier frequency CF. It outputs to the register in the phase data generation section 502, and also outputs the corresponding address data FA and setting data ED to the register in the envelope generator 513, and further,
The corresponding PCM start address AsP is output to the register of PCMC address generation 04. Note that the transport start address A output to the transport address generation unit 503
SM is a fixed value. As a result, the phase data generator 5
02 and envelope generator 513 start generating phase data PH and envelope signal E at time division timing corresponding to the assigned sound generation channel,
Furthermore, based on this, the transport address generation unit 503 and the PC
The MC address generation 04 starts generating the carrier address ωCτ(M) and the PCM address ωCT(P), and musical tone synthesis in that sound generation channel is started.

At the same time, the controller 501 controls the selector control signal S0 for each sound generation channel. As a result, the connection state of the selectors 505 and 510 is changed for each sound generation channel, and it is selected whether musical tone synthesis is to be performed by the PCM method or by the modulation method based on the principle configuration shown in FIG.

In addition to the above configuration, the embodiment shown in FIG.
It has a shift register 514 that holds data for each sampling period (one data at a time). This shift register 514 is
A data shift operation is performed according to clocks φ1 and φ2 from the controller 501. The delay output from the shift register 514 is input to the ADD 507 via the terminal B of the selector 508 as a modulation signal W9. As a result, when musical tone synthesis is performed using a modulation method in any sound generation channel, it is possible to modulate the modulation waveform output eM one sampling period before the original sound channel as the modulation signal WM, resulting in extremely deep modulation. A modulated waveform output e9 can be obtained.

An example of a specific operation timing chart of the above-mentioned operation is shown in FIG. In the same figure, even-numbered sound channels are used to
This is an example in which musical tone synthesis is performed using the M direction, and musical tone synthesis is performed using a modulation method using odd numbered sound generation channels. .

Phase data PH, PCM address ωcT (P), carrier address (c) ct (M), carrier signal Wc, PCM
Signal O1, addition waveform Wc+WM, decode output OM, P
The CM waveform output eP, the modulated waveform output eM, and the envelope signal E each output data corresponding to the sound generation channel at the time division timing at each time division timing from 0 to 32 in FIG. 10(a). Also, from the shift register 514, as shown in FIG. 10(d), the 10th
PCM waveform output ep (even numbered sound generation channel) or modulated waveform output eM (odd numbered sound generation channel) at the same time division timing as 0 to 32 in Figure (a) and one sampling period earlier
is output as a delay output. The delay output 1)-1 from latch 515 in FIG. 10(e) is not considered in this example.

Selector control signal S. 10th figure)
[ff1(a) Selectors 505 and 510 select each terminal A at the time division timing of the even numbered sound generation channels, and select each terminal B at the time division timing of the odd numbered sound generation channels. Further, the selector control signal S1 always causes the selector 508 to select the delay output input from the terminal B, as shown in FIG.
2 always selects the envelope signal E input from the terminal A. The phase data generator 502, envelope generator 513, and shift register 514 are shown in FIG.
According to the clocks φ1 and φ2 shown in b) and (C),
It operates in synchronization with each time division timing shown in FIG. 10(a).

According to the operation example shown in the above operation timing, the 10th
In the even numbered sound generation channels in figure (a), PCM
PCM address ωCT(P
) is input to the waveform ROM 506 via the selector 505. Then, the PCM signal 0. is input to the MtJL511 via the selector 510, an envelope based on the envelope signal is added here, and the PC
M waveform output ep is obtained. As a result, musical tone synthesis using the PCM method is executed. Furthermore, in the odd-numbered sound generation channels in FIG. 10(a), the transport address ωct(M) from the transport address generation unit 503 is
5 to the waveform ROM 506, a carrier signal Wc is output. Then, in the ADD 507, the delay output D (modulated waveform output eM) of the spontaneous sound channel one sampling period before is added to the carrier signal Wc as the modulated signal WM.
The resulting sum waveform Wc+W
M is input to the triangular wave decoder 509. Then, the decoded output OM from the triangular wave decoder 509 is output to the selector 5.
The signal is inputted to the MUL 511 via the signal line 10, where an envelope by an envelope signal is added to obtain a modulated waveform output eM. As a result, tone synthesis using the modulation method is executed.

The modulated waveform output eM of the PCM waveform output sentence obtained as described above is outputted to the accumulator 516 as a delay output from the shift register 514, and is output to the left channel output and right channel output R by the operation described later. After being converted into analog musical tone signals by each D/A converter 519 (L, R) and low-pass filter (LPF, the same applies hereinafter) 520 (L, R), each amplifier 521 (L
, R), and each speaker 522 (L, R)
Kara m sound is heard.

Subsequently, in the embodiment of FIG. 5, the shift register 514
It further includes a latch 515 that holds the delay output from the circuit for one time division timing. This latch 515 performs a delay operation corresponding to one time division timing in accordance with clocks φ1 and φ2 from the controller 501. Then, the delay output D-1 from the latch 515 is sent to the selector 508.
The modulation signal WM is input to the ADD 507 via the terminal A of the modulation signal WM. As a result, when tone synthesis using a modulation method is performed in an arbitrary sound generation channel, the modulation waveform output e of the other sound generation channel one sampling period before. Alternatively, the PCM waveform output ep can be modulated as the modulation signal WM, and a modulated waveform output eM that is more effectively modulated can be obtained. In particular, various function waveforms such as sine waves, sawtooth waves, rectangular waves, etc. are stored in the PCM signal area of the waveform ROM 506, and these are read out as PCM waveform output statements, and as described later, those function waveforms are stored. By controlling the waveform so that it is not directly output from the accumulator 516, it is also possible to provide modulated signals WM of various function waveforms as the delay output D-1 that is delayed from the PCM waveform output. The strength of the modulation signal WM in this case can be controlled by the envelope signal added in the MUL 511 to the PCM signal 0°.

Furthermore, in the present embodiment, the controller 501 receives an envelope control state signal ADS from the envelope generator 513 indicating the control state of the envelope after the start of key depression.
By taking in R, the state of the selector control signal S0 can be changed in any sound generation channel according to the control state of the envelope after the start of key depression.

As a result, for example, in each of the attack section, decay section, sustain section, release section, etc.
It is also possible to change the tone synthesis method.

An example of a specific operation timing chart of the above-mentioned operation is shown in FIG. Similar to FIG. 10, this figure shows an example in which tone synthesis is performed using the PCM method on even-numbered sound generation channels, and musical tone synthesis is performed using the modulation method on odd-numbered sound generation channels.

Here, FIGS. 11(a) to (c) are the same as FIG. 10(a) to (f) and (c). However, in this operation example, for the sound generation channel No. 31 in FIG. 11(a), the controller 501 in FIG.
It incorporates DSR. And controller 501
By determining the attack, decay, sustain, and release sections, as shown in Figure 11 ((2),
In the attack section A and release section R, the selector 50
B controls the selector control signal S so as to select the delay output D-1 input to the terminal A, and in the decay interval and sustain interval S, the selector 508 selects the delay output input to the terminal B. The selector control signal S1 is controlled as follows.

According to the operation example shown in the above operation timing, the 11th
In the sound generation channel No. 31 in Figure (a), in the attack period A and the release period R, the PCM waveform output eP of the No. 30 sound generation channel l sampling period before is used as the modulation signal WM, and musical tone synthesis using the modulation method is performed. During the decay period and the sustain period S, the modulation waveform output e8 of the spontaneous sound channel one sampling period before is converted into the modulation signal W1. As I, musical tone synthesis is performed using a modulation method.

In addition to the above-mentioned operation example, settings can be made such that in any sound generation channel, musical tone synthesis is performed using the PCM method in the attack section and release section, and musical tone synthesis is performed using the modulation method in the decay section and sustain section. is also easy.

FIG. 12 shows the relationship between the control states of the selector control signals S0, Sl, and S2 and the tone synthesis method realized in FIG. 5 accordingly.

First, as shown in FIG. 12(a), <, S, causes the selectors 505 and 510 to always select each terminal A, and Sl is undefined.
, S2 are set so that the selector 512 always selects the envelope signal E input to the terminal A, musical tone synthesis is performed using the PCM method.

Next, as shown in FIG. 12(b), So sends each terminal A to the selectors 505 and 510 using even numbered sound generation channels.
is selected, each terminal B is selected in the odd-numbered sounding channel, SI causes selector 508 to always select the delay output input to terminal A, and S2 selects selector 512.
When the envelope signal E input to terminal A is set to be always selected for Musical tone synthesis is performed using this method. In this case, the PCM waveform output ep
is a function waveform such as a sine wave, sawtooth wave, or rectangular wave. Further, the PCM waveform output ep is output from the accumulator 516 in FIG.
(This operation will be explained later).

Further, as shown in FIG. 12(C), So causes selectors 505 and 510 to always select each terminal B, Sl causes selector 508 to always select the delay output input to terminal B, and S2 When the selector 512 is set to always select the envelope signal E input to the terminal A, the modulation waveform output eH (delay output D) of the spontaneous sound channel one sampling period before is set as the modulation signal WA. Musical tone synthesis is performed using a modulation method.

Furthermore, as shown in FIG. 12(d), SIl+ is selected by the selector 50.
5 and 510, each terminal A is selected in the even numbered sound generation channel, each terminal B is selected in the odd numbered sound generation channel, and S2 is set to terminal B to the selector 512. When the delay output D-1 is set to be always selected, musical tone synthesis is performed using the ring modulation method using the PCM waveform output ep (delay output D-1) of the adjacent sound generation channel one sampling cycle earlier as the envelope. will be held. In this case, Fig. 12(b)
As in the case of , the PCM waveform output ep is controlled so as not to be output from the accumulator 516 in FIG.

Then, as shown in FIG. 12(d), So is the selector 505.
and 510 select each terminal A in the even-numbered sound generation channels, select each terminal B in the odd-numbered sound generation channels, and Sl always selects the delay output input to the terminal B for the selector 508. and S2 is the selector 51.
2, if the delay output p-1 input to terminal B is set to be always selected, the PCM waveform output ep (
The delay output D -1) is used as an envelope, and the modulated waveform output eM (
Musical tone synthesis is performed using a ring modulation method using the delay output D) as a modulation signal WM. In this case as well, the PCM waveform output e is controlled so as not to be output from the accumulator 516 in FIG.

As described above, in this embodiment, it is possible to freely mix various tone synthesis methods for each sound generation channel.

Next, the configuration of accumulator 516 in FIG. 5 is shown in FIG. 13.

Of these, FIG. 13(a) shows the circuit portion that distributes the musical sound waveform obtained as the delay output in FIG. 5 to the left channel output and the right channel output R, and FIG. 13(b)
), the selector control signal SWO for controlling the opening/closing of the selector 131 in FIG.
This is a decoder circuit that generates data based on panning control data PAN and clock CT input from the PAN controller.

In the operation of the accumulator 516 in FIG. 13(a), each of the 32 time-division intervals corresponding to the 32 sound generation channels within each sampling period is the left channel of the first half that becomes the clock CT Caroleher, as will be described later. It is divided into a processing period and a right channel processing period in the second half in which the clock CT is at a high level, and is connected to the ADDI 302 and two stages of latches 130 in series.
3 and 1304, an accumulation operation is performed for each left and right channel.

That is, if the selector 1301 is turned on in the left channel processing section within that time division section, the delay output of each sound generation channel input in each time division section is A.
In the DD 1302, the left channel accumulated value output from the launch 1303 is accumulated. On the other hand, selector 1301
is turned on in the right channel processing section within the time division section, the ADD 1302 accumulates the right channel cumulative value output from the latch 1303. Furthermore, when the selector 1301 is turned on during all sections within the time-division section, the left channel accumulated value and the right channel accumulated value are accumulated in the ADD 1302, respectively, which are successively output from the latch 1303. Furthermore, if the selector 1301 is not turned on in that time division interval, the delay output of that sound channel is not input to the accumulator 516 in FIG. Used only as WM.

Then, the left channel accumulated value is obtained by accumulating the delay output of the 32nd sounding channel as necessary in the left channel processing section of the 32nd sounding channel's time division interval at the end of each sampling period. After that, it is turned on to the left channel output latch 1305 and output as the left channel output. In addition, the right channel cumulative value is
In the right channel processing section of the time-division section of the same <32nd sounding channel, the ADD 1302 accumulates the delay output of the 32nd sounding channel as necessary, and then it is latched by the right channel output latch 1306, and the delay output of the 32nd sounding channel is It is output as output R.

Here, latches 1303 and 1304 in FIG. 13(a)
is operated by the clocks φsI and φ,2 from the controller 501 in FIG.
05 and the right channel output latch 1306 receive the clock φ from the controller 501.

and φR.

Further, the selector 1301 in FIG. 13(a) is controlled to open and close by a selector control signal SWO from the decoder section in FIG. 13(b).

13, etc.), the pan control data PAN from the controller 501 in FIG. 5 is 2-bit data PAN.
A predetermined set of data is set for each of 32 time-division intervals corresponding to 32 sound generation channels. The AND circuit 1310 receives input signals obtained by inverting the pan control data PANO1PANI and the clock CT by inverters 1307, 1308 and 1309, respectively. The AND circuit 1311 receives the pan control data PANO and the clock CT.
A signal obtained by inverting NI by an inverter 1308 is input.

Furthermore, the AND circuit 1312 receives pan control data PAN.
A signal obtained by inverting O by an inverter 1307 and pan control data PANI are input. And AND circuit 1310.
Each output of 1311 and 1312 is input to an OR circuit 1313, and a selector control signal SWO is obtained as its output.

Now, if you want to output the delay output of the sound generation channel as the left channel output, in the time division interval corresponding to that sound generation channel, PAllO=0, PAN1=
O is set. As a result, in the first half left channel processing section in which the clock CT in that time division section is at a low level, the output of the ant circuit 1310 becomes a high level, and the selector control signal SWO, which is the output of the OR circuit 1313, becomes a high level. Become. As a result, the selector 1301 in FIG. 13(a) is turned on in the left channel processing section within that time division section.

On the other hand, if you want to output the delay output of the sound generation channel as the right channel output R, in the time division interval corresponding to that sound generation channel, PANO = 1, PAN1 = O
is set. As a result, in the right channel processing section in the latter half of the time division period in which the clock CT is at a high level, the output of the AND circuit 1311 becomes a high level and the selector control signal S, which is the output of the OR circuit 1313.
WO becomes high level. As a result, the selector 1301 in FIG. 13(a) is turned on in the right channel processing section within that time division section.

Also, if you want to output the delay output of the sound generation channel as both the left channel output and the right channel output R, in the time division interval corresponding to the sound generation channel,
PANO=01PANl=1 is set. As a result, regardless of the state of the clock CT, the output of the AND circuit 1312 becomes high level and the selector control signal SWO, which is the output of the OR circuit 1313, becomes high level in the entire time division period. As a result, the selector 13 in FIG. 13(a)
01 is turned on.

Furthermore, if you wish to use the delay output of a sound generation channel only as a modulation signal WM via terminal B of the selector 508 without inputting it to the accumulator 516 in FIG. In the interval, PANO = 1
, PAN1=1 is set.

As a result, in that time division interval, the AND circuit 1310
．． Neither 1311 nor 1312 is turned on, and the selector control signal SWO remains at low level. As a result, the selector 1301 in FIG. 13(a) is not turned on in that time-division period.

As described above, the accumulator 516 has the configuration shown in FIGS. 13(a) and 13(b).
A specific example of the operation will be explained with reference to the operation timing chart of FIG.

In the example in the same figure, in the time division interval corresponding to the 30th and 31st sound generation channels ((f) in the same figure, the same applies hereinafter), the PAN
Because O= 01PAN1=O (the same figure (barrel, (h)
In the left channel processing section where the clock CT ((a) in the same figure, the same hereinafter) is at a low level, the selector control signal SWQ ((i) in the same figure, the same hereinafter) becomes high level, and the selector 1301 turns on.

Then, at the rising timing of the clock φSl ((b) in the same figure, the same applies hereinafter) within the same period, ADD 130
2, the delay output signal is accumulated in the left channel accumulated value output from the latch 1303, and the clock φ,2(
The signal is latched by the latch 1304 at the rising timing of (C) in the figure (the same applies hereafter).

On the other hand, during the time division interval corresponding to the sound generation channel number 0, PANO = 1 and PAN1 = O, so the selector control signal SWO is high in the right channel processing interval where the chronograph CT is high level. level, and the selector 1301 is turned on. Then, the clock φ5 within the same interval. At the rising timing of clock φ,2, the delay output signal is accumulated in the right channel accumulated value outputted from latch 1303 in ADD 1302, and latched by latch 1304 at the rising timing of clock φ,2.

Also, in the time division interval corresponding to the first sound channel,
Since PANO=01PAN1=1, the clock C
Regardless of the state of T, the selector control signal SWO is at a high level in both the left channel processing section and the right channel processing section, and the selector 1301 is turned on. Then, at the rising timing of the clock φ, I in the left channel processing section, the delay output is accumulated in the left channel accumulated value output from the latch 1303 in the ADD 1302, and the delay output is accumulated at the timing of the rising edge of the clock φ, 2. is latched by the launch 1304, and at the timing of the rise of the clock φ, 1 in the subsequent right channel processing section, the delay output is accumulated in the right channel accumulated value successively output from the launch 1303 at ADD1'302. , are latched following launch 1304 at the rising timing of clock φS2.

Furthermore, in the time division interval corresponding to the second sound generation channel,
Since PANO=1 and PAN1=1, the selector control signal SWO is at a low level during the entire period, and the selector 1301 remains off. As a result, the delay output becomes the modulated signal W. (Figure 5) Used only as an article.

Then, number 31 (32
In the left channel processing section where the clock CT of the time division section corresponding to the th sound generation channel is at a low level,
At the rising timing of clocks φ and I within the same interval, the left channel accumulated value output from the latch 1303 is accumulated with the delay output input from the selector 1301, and the accumulated value is The value is latched in the left channel output latch 1305 at the rising timing of the clock φL (FIG. 14(d), the same applies hereinafter), and is output as the left channel output L (Tn-,). This output value is held by the left channel output latch 1305 for one sampling period, and after being converted into an analog tone signal by the D/A converter 519 (L) and LPF 520 (L) in FIG. 521 (L), and the sound is emitted from the speaker 522 (L).

Similarly, the clock CT of the time division interval corresponding to the 31st (32nd) sound generation channel of the sampling period T0-1.
In the right channel processing interval where is at a high level, the right channel accumulated value is output from the latch 1303 at the timing of the rise of the clock φs1 in the same interval, and the right channel accumulated value is output from the latch 1303 at the timing of the rise of the clock φR (FIG. 14(e), the same applies hereinafter). At the timing, the accumulated value passes through the ADD l 302 (in this example, accumulation is not performed at the same timing), is latched by the right channel output latch 1306, and is output as the right channel output R('rn −+ ) is output. This output value is held in the right channel output latch 1306 for one sampling period, and the D/A converter 5 in FIG.
After being converted into an analog musical tone signal by 19(R) and LPF520(R), it is amplified by amplifier 521(R),
Sound is emitted from the speaker 522(R).

The above-mentioned output operation is performed at other sampling periods T7, T n
The same applies to +1.

In the above embodiment of the present invention, the waveform ROM 5 in FIG.
06, as shown in FIG. 7, stores only one type of carrier signal Wc having the characteristics shown in FIG. 2, and the three-horse wave decoder 509 shown in FIG. However, instead of being limited to this, waveforms such as those shown in the right column of FIGS. A ROM or the like that stores waveforms such as those shown in the left column of FIGS. (a) to (d) may be provided and operated selectively.

〔Effect of the invention〕

According to the present invention, after the instruction to start sounding, for example, the attack part or the attack part and release part of the musical tone is transmitted to the modulated musical tone signal generating means from the PCM waveform signal generating means.
A waveform signal is given as a modulation signal to generate a modulated musical tone signal, and in other parts, such as a sustain section and a decay section, the normal waveform signal from the normal waveform signal generating means is modulated to the modulated musical tone signal generating means. It can be applied as a signal to generate a modulated musical tone signal. As a result, for example, it is possible to generate musical tones with very characteristic, complex, and diverse characteristics in the attack section, release section, etc., and it is possible to greatly change the characteristics in other sections.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a musical sound waveform generator using a modulation method, which is the basis of the present invention. FIG. 2 is a diagram showing the storage contents of a carrier wave ROM. FIG. 3 is a diagram of a musical sound waveform generator using a modulation method. 4(a) to 4(d) are diagrams showing other aspects of the stored waveforms of the carrier wave ROM and the triangular wave decoder in FIG. 1, and FIG. 5 is an illustration of the operation when no modulation is performed. A configuration diagram of a specific example, FIG. 6 is a configuration diagram of a triangular wave decoder, FIG. 7 is a data configuration diagram of a waveform ROM, and FIGS.
(C) is a relationship diagram between phase data, PCM address, and PCM signal, Figures 9 (a) to (C) are relationship diagrams between phase data, carrier address, and carrier signal, and Figures 10 (a) to (5). ) is an operation timing chart of the first operation example of the specific embodiment of the present invention, FIG. 11(a)
~(i) is an operation timing chart of the second operation example of the specific embodiment of the present invention, and FIG. 12 is an operation timing chart of So, Mi, and S
13(a) and 13(b) are block diagrams of the accumulator 516, and FIGS. Operation timing charts of operation examples, FIGS. 15(a) to 15(C) are envelope waveform diagrams of musical tones. 501... Controller, 502... Phase data generation section, 503... Transport address generation section, 504... 505, 506... 507... 509... 511... 513... 514... 515... 516... 517... 518... CF... PH... ASP... AsMo. ωCT (p) ωCT (M) OP... PCM address generator, 08.510.512...Select waveform ROM, adder (ADD), triangular wave decoder, multiplier (MUL), enherobe generator, shift Register, latch, accumulator, keyboard section, switch section, carrier frequency, phase data, PCM start address, transport start address, ... PCM address, ... transport address, PCM signal, Wc ... WM ... Wc +W. OM・・・eP゛°. eM ° ° ・ D, D-1 ・ E ・ ・ ・ Engineering

Claims (1)

[Claims] Modulated musical tone signal generating means for generating a modulated musical tone signal by converting a mixed output obtained by mixing a modulated signal with a carrier signal based on a predetermined functional relationship, and a PC using a PCM system.
PCM waveform signal generation means for generating an M waveform signal; normal waveform signal generation means for generating a normal waveform signal other than the PCM method; and control means for generating the modulated musical tone signal by temporally switching between the PCM waveform signal from the means and the normal waveform signal from the normal waveform signal generating means and providing the modulated signal as the modulated signal. Musical sound waveform generator.