JPH0365997A - Musical sound synthesizer - Google Patents

Abstract

PURPOSE:To control the Q of the resonance of a resonance circuit corresponding to the timbre of a musical instrument by interposing signal attenuating means in a transmission line where an exciting signal outputted by an exciting means is fed back to the exciting means again through the resonance circuit. CONSTITUTION:The signal attenuating means A1, A2 and A3 are interposed in the transmission line where the exciting signal outputted by the exciting means 10 is fed back to the exciting means 10 again through the resonance circuit 30 and the signal attenuation quantity is controlled. A multiplier M4 multiplies the output signal of a low-pass filter LPFTH by a reflection coefficient the corresponding to an air pressure wave at a tone hole TH opening part. this reflection coefficient thc is supplied from a musical sound control circuit 100 when the musical sound is generated and a musical sound control circuit 100 detects the manipulated variable of an operation element, so that the height of the Q of resonance of the resonance circuit 30 can be specified corresponding to the manipulated variable. Consequently, the Q of the resonance of the resonance circuit can be controlled and flexible performance control is performed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a musical tone synthesis device particularly suitable for use in synthesizing wind tone tones.

``Prior Art'' A method is known in which a model obtained by simulating the sound generation mechanism of natural music 21 is operated, thereby synthesizing the musical tones of a natural musical instrument. The most basic model for wind instruments such as the clarinet is a model with a closed-loop structure that connects a nonlinear amplification element that simulates the elastic characteristics of a reed and a resonant circuit that simulates a resonant tube. There is. In this model, when a signal is output from the nonlinear amplification element, this signal is input to the resonant circuit as a traveling wave signal, and a feedback signal from the resonant circuit,
That is, a signal corresponding to a reflected wave from the resonance tube is fed back to the nonlinear amplification element. In this way, the propagation of air pressure waves in wind music is faithfully simulated by the closed loop circuit consisting of the nonlinear amplifying element and the resonant circuit.

In addition, actual wind instruments are provided with holes for controlling pitch, so-called tone holes, and models that simulate wind instruments including these tone holes are known. This model has a resonant circuit that has multiple bidirectional transmission circuits and a circuit called a signal scattering junction (hereinafter abbreviated as junction) that performs signal processing corresponding to tone holes between each bidirectional transmission circuit. is used. Each junction performs arithmetic processing such as coefficient multiplication on each input signal from an adjacent bidirectional transmission circuit, and the arithmetic results are supplied to the adjacent bidirectional transmission circuit. The multiplication coefficients and the like in this arithmetic processing are switched depending on the open/closed state of the tone hole.

In this case, the signal fed back to the nonlinear amplification element is the sum of the components folded back at each junk signal. Moreover, as mentioned above, since the multiplication coefficient for calculation in each junk signal is switched depending on the open/closed state of the tone hole, the transmission amount frequency characteristics of the resonant circuit are eventually switched depending on the open/closed state of the tone hole. It will be done. More specifically, the transmission frequency characteristics of the resonant circuit are determined by the frequency corresponding to the delay time until the output signal of the nonlinear amplification element is folded back at the junk signal corresponding to the open tone hole and fed back to the nonlinear amplification element. (first order) and each frequency (higher order) that is an integer multiple thereof has a multimodal characteristic.

On the other hand, in the nonlinear amplification element, by changing the bias point of nonlinear amplification depending on the input signal, it is possible to equivalently change the amplification factor for each frequency component. Therefore, by this amplification control, it is possible to switch the component to be emphasized among the frequency components circulating in the nonlinear amplification element and the resonant circuit.

In this way, it is possible to simulate, for example, pitch changes over an octave or more of the range that appear when the blowing pressure is changed in a wind instrument. Note that this type of technology is disclosed in, for example, Japanese Patent Laid-Open No. 63-40199.

"Problem to be Solved by the Invention" By the way, in the conventional musical tone synthesis device described above, when trying to switch the order of the resonant frequency of the resonant circuit by changing the bias point of the nonlinear amplification element, each of the resonant circuits It is desirable that the resonance Q (selectivity) near the resonance frequency be low. Conversely, when generating musical tones with stable frequencies, it is desirable to increase Q. As described above, there is a demand for switching the resonance Q of the resonant circuit to a desired level to suit the playing style. Furthermore, when the Q of resonance in the resonant circuit is increased, a rich sound containing many frequency components is generated, and when the Q of resonance is increased, the sound becomes sharp. Therefore, when trying to realize the tones of various musical instruments, a function to control the Q of resonance is essential.

The present invention has been made in view of the above-mentioned circumstances, and provides a musical tone synthesis device that is capable of controlling the Q of resonance in a resonant circuit in response to a desired performance form or a desired tone of a musical instrument. is intended to provide.

"Means for Solving the Problems" In order to solve the above problems, the present invention provides a plurality of signal processing means that performs predetermined signal processing on each forward and reverse input signal and outputs each input signal, and each of the above-mentioned signals. At least one means for connecting the signal processing means, which performs predetermined arithmetic processing on the output signal of each connected signal processing means and supplies the result of the arithmetic operation to the signal processing means as an input signal. comprising a resonant circuit constituted by a signal scattering junction, and excitation means that generates an excitation signal based on an input signal to itself and a feedback signal from the resonant circuit, and inputs the excitation signal to the resonant circuit, Further, a signal attenuation means is inserted in a transmission path until the excitation signal outputted from the excitation means is fed back to the excitation means via the resonant circuit, and the amount of signal attenuation in the signal attenuation means is controlled. It is characterized by the following.

"Operation" According to the above configuration, since the signal attenuation means is inserted in the transmission path until the excitation signal outputted from the excitation means is fed back to the excitation means via the resonant circuit,
Negative feedback is performed according to the amount of signal attenuation by the signal attenuation means.

Therefore, the above transmission path operates with negative feedback amplification reduced, and when the signal attenuation is increased, the resonance Q of the resonant circuit is lowered,
When the amount of signal attenuation is reduced, the resonance Q becomes higher.

"Example" Hereinafter, one embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of a musical tone synthesizer according to an embodiment of the present invention. Moreover, FIG. 2 shows the constituent countries of the physical model of the clarinet simulated by this musical tone synthesizer.

First, the physical model shown in FIG. 2 will be explained.

In FIG. 2, 1 indicates the resonance tube (tube section) of the wind instrument, 2 indicates the mouthpiece section, 2a indicates the reed, TI indicates one tone hole formed in the resonance tube 1, and RTC indicates the register tube.

The clarinet's sound production mechanism will be explained below with reference to this physical model. When a blow player holds the mouthpiece portion 2 in his mouth and blows into it, the reed 2a is displaced due to the blowing pressure P and its own elasticity (arrow 2S). As a result, an air pressure wave (compression wave) is generated inside the tube of the lead 2a, which becomes a traveling pressure wave F and is sent toward the terminal end IE of the resonance tube l. Then, the traveling pressure wave F is reflected at various places in the resonance tube I and at the terminal end IE, and returns to the lead 2a as a reflected pressure wave R, and the lead 2a receives the pressure PR from the reflected pressure wave R. Therefore, while playing,
The total pressure PA that the lead 2a receives is PA = P - PR (1), where the pressure of the reflected pressure wave R is PR.In the end, the lead 2a has its own elastic characteristics and the above pressure PA. vibrates due to Then, the vibration of the reed 2a and the reciprocating motion of the pressure waves F and R within the resonance tube 1 resonate, thereby generating a musical tone.

The primary resonance frequency at this time is switched by opening and closing a tone hole TH formed in the resonance tube 1. That is, when the tone hole TH is opened and closed, the flow of pressure waves in the vicinity of the tone hole TH changes accordingly, and the effective length of the resonance tube 1 changes, so that the resonant frequency is switched. Ru.

Hereinafter, the state of the air pressure wave at a point j near the tone hole T H of the resonance tube l will be explained.

When the tone hole TH is open> When the tone hole TH is open, the air pressure Pj at point j is: Pj=a+ofr p, + + atoHp, + a
soN P3+...(2). Here, Pl+ is the pressure of the air pressure wave flowing into point j from the lead 2a side of the resonance tube 1, P, + is the pressure of the air pressure wave flowing into point j from the end IE side of the resonance tube 1, and P, +i indicates the pressure of the air pressure wave flowing from the tone hole TH. Also, alofL aton and a
sorf is a coefficient corresponding to the contribution of each air pressure wave flowing into point j to the air pressure P3 at point j, and is expressed by the following formula (3)
It is given by ~(5).

a, on = 2φl′/(φ1′+φ1+φ,”)
−・・−(3) a*orr=2φ? /(φd+φ1+
φ,”) −−−−−−(4) asoH= 2φ,′
/(φ11+φ1+φ3')...(5) Here, φ is the diameter of the lead 2a side part of the resonance tube l, φ is the diameter of the terminal end IE side of the resonance tube l, and φ is the tone Hall T
Indicates the diameter of H.

On the other hand, in FIG. 2, from point j to lead 2a of resonance tube l
The pressure P of the air pressure wave flowing out in the direction of -1 resonance tube, the pressure P of the air pressure wave flowing out in the direction of the resonance tube end IE, and the pressure of the air pressure wave flowing out to the tone hole TI (P).
s-, these are respectively pt-=p3-p, + ・
...(6) P, -=Pj-P, + ...
(7) Ps”= Pj P3+ (8
).

An air pressure wave (pressure p
l) eventually reaches the terminal end lE and part of the lead 2a
However, in the case of a wind instrument with an open end, such as a clarinet, the phase is reversed during this reflection. Also, if Tone Ho/L/T I-[ is in the open state,
The air pressure wave (pressure P, -) flowing out from point j toward the outside of the tone hole TH is reflected at the opening, but in this case as well, the traveling wave is reflected in the opposite phase.

Case in which the tone hole TH is in an open state> In this case, it is considered to be equivalent to a state in which the diameter φ of the tone hole TH is O. Therefore, the above formula (3) ~
By substituting φ and =O into (5), the air pressure Pj of each air pressure wave when the tone hole TH is in the closed state
Coefficient 11 corresponding to the degree of contribution to on, anon,
ason is derived as shown in the following formulas (9) to (l l).

a+on=2φ1′/(φ−1φm”) −・・・
・(9) amon= 2φ1/(φ,′+φm”)
−・−・−(10) a−on=0
-- (11) And the air pressure Pj at point j is P j"a+on P 14 + axon P t+
a@On P s” (12).

Signals reflected at various points in the resonance tube 1 as described above are fed back to the lead 2a, and the primary resonance frequency is determined by the most effective component of the signals. When the tone hole TH is in an open state, the primary resonance frequency is determined by the time required for the air pressure wave to travel back and forth between the lead 2a and the tone hole TH. In addition, the transmission amount frequency characteristic of the resonance tube 1 in this case is a multimodal characteristic in which the transmission gain is maximum at the first-order resonance frequency and higher-order resonance frequencies such as 3 times, 5 times, etc. becomes.

Next, the resistor tube RTC will be explained.

As mentioned above, the resonance tube l of a wind instrument has a multimodal transmission frequency characteristic, and the resistor tube RTC is provided to promote resonance at a higher resonance frequency in the resonance tube l. be. Among existing wind instruments, there are wind instruments that are equipped with holes (called octave keys) corresponding to register tubes RTC in order to facilitate pitch switching over one octave or more. As shown in Figure 2,
At points near the resistor tube RTC, scattering of air pressure waves occurs. Q I ”+ Q l ”+ Q 3
+ is the pressure of the air pressure wave flowing into the neighboring point k, Q, -, Q
,−,Q,− is the pressure of the air pressure wave flowing out from the neighboring point k. When the resistor tube RTC is closed,
The components of the air pressure wave that are returned to the lead 2a are predominantly those that are reflected and returned at the tone hole TH or the end portion IE. On the other hand, resistor tube RTC
When the resistor tube RTC becomes open, the scattering of air pressure waves at the resistor tube RTC becomes significant, so that the component reflected at the resistor tube RTC is emphasized in the air pressure wave that is fed back to the lead 2a. Note that the scattering of the air pressure wave at this point k is similar to the case at the point j near the tone hole TH mentioned above, so here ffl
? The detailed explanation will be omitted.

Next, the musical tone synthesis apparatus shown in FIG. 1 constructed based on the physical model shown in FIG. 2 will be explained. In the figure, an excitation circuit 10 corresponds to the mouthpiece section 2 in FIG. 2, and a resonance circuit 30 corresponds to the resonance tube 1. Furthermore, the jumper 920 inserted between the excitation circuit 10 and the resonance circuit 30 simulates the scattering of air pressure waves at the connection between the mouthpiece section 2 and the resonance tube 1.

In this junksign 20, the output signal from the resonant circuit 30 and the output signal from the excitation circuit 10 are added by the adder 18 and input to the resonant circuit 30, and the output signal from the adder 18 and the output signal from the resonant circuit 30 are added together. 119 and input to the excitation circuit 10.

The excitation circuit 10 includes subtractor IL filters 12 and 13,
Adder 14, ROM15, Multiplier 16.17 and IN
It consists of V. When a musical tone is generated, information corresponding to the blowing pressure P and the embouchure E (the pressure when the mouthpiece is held in the mouth) is given from the musical tone control circuit lOO.

For subtraction 2311, from resonance circuit 30 to junk circuit 2
0, that is, a signal corresponding to the air pressure PR of the reflected wave R from the resonance pipe 1 in FIG. 2, and a signal corresponding to the blowing pressure P are input. Then, the above equation (1) is calculated, and the air pressure P applied to the lead 2a is
A signal corresponding to A is obtained.

The output signal of the subtracter 11 is band-limited by a filter 12. This filter 12 is constituted by a first-order low-pass filter, and is inserted to prevent the amplitude of the signal applied between the excitation circuit 10 and the resonant circuit 30 from becoming significantly large at a specific frequency. Then, the output signal P of the filter 12 is input to the filter 13, inverted by the multiplication 'aINV, and input to the multiplier 16. The signal P passes through the filter 13 to remove high frequency components. This simulates the response characteristics of the lead 2a that absorbs sudden pressure changes.

Then, the adder 14 adds a signal corresponding to the embouchure E to the output signal p of the filter 13 to obtain a signal P corresponding to the pressure actually applied to the lead. This signal P3 is then given to the ROM 15 as an address. As a result, a table of nonlinear functions stored in advance in the ROM 15 is referred to, and the cross-sectional area of the gap between the reed 2a and the mouthpiece portion 2, that is,
A signal Y corresponding to the admittance to the airflow is output. Then, the signal Y and the signal -P are multiplied by the multiplier 16, and a signal FL corresponding to the flow velocity of air passing through the gap between the reed 2a and the mouthpiece portion 2 is obtained.

Then, the multiplier 17 multiplies the signal FL by a multiplication coefficient G. Here, the multiplication coefficient G is a constant determined according to the pipe diameter near the attachment of the mouthpiece part 2 in the resonance pipe 1, and the difficulty in passing the airflow, that is,
It corresponds to the impedance to air flow.

Therefore, multiplication? From 317, a signal corresponding to the air pressure change occurring in the mouthpiece side of the resonance tube 1 is obtained. And this signal is Jankushi9in20
The signal is input to the resonant circuit 30 via.

In the resonant circuit 30, delay circuits D jf, D kr
, Dsr, D @r, D kr+ D jr are
Each corresponds to the propagation path of the air pressure wave within the resonance tube 1 in FIG.

More specifically, the lead 2a and the resistor tube RT
The propagation delay of the air pressure wave between the resistor tube RTC and the tone hole TH is simulated by the delay circuits Djr and Dir, the propagation delay between the resistor tube RTC and the tone hole TH is simulated by the delay circuit Dkr and Dkr, and the propagation delay of the air pressure wave between the tone hole TI (The propagation delay between IE and termination IE is simulated by delay circuits Dmf and Dtrr.

When the output signal of the resonant circuit 30 is input to the termination circuit TRM, it is band-limited by the low-pass filter ML, further multiplied by a negative coefficient γ by the multiplier IV, and then returned to the resonant circuit 30. In this way, the frequency characteristics of the acoustic loss at the termination IE and the phase reversal due to reflection are slated.

The junction JTH in the resonant circuit 30 simulates the scattering of the air pressure wave at a point j near the tone hole T)l in FIG.
j1 multiplier M,, M,, M,, M,, subtractor A r, A □A s% delay circuit DTH,, DTH
, and a low-pass filter LPFTH. The adder Aj receives a signal obtained by multiplying the output signal of the delay circuit Dkr (corresponding to the pressure P in FIG. 2, 10) by a coefficient 31 by a multiplier M, and the output signal of the delay circuit Dmr (corresponding to the pressure P in FIG. 2). .

A signal obtained by multiplying the output signal of the delay circuit DTH (corresponding to the pressure P3+ in Fig. 2) by a coefficient a by a multiplier M3 is input. be done. Also, each coefficient aln aln as
When the tone hole TH is in an open state, the coefficients a+oN, asoH, asolf according to the above equations (3) to 5) are given from the musical tone control circuit lOO, and when the tone hole TH is in an open state, is the above formula (9) ~ (
ll) coefficient a + On + 11 t On
+83On is given.

Then, the addition result of addition 2'A A J, that is, a signal corresponding to the air pressure Pj at point j, is sent to a subtractor A8.

and A, are input. Then, in subtraction 5A, the output signal (pressure p, equivalent to 10) of the delay circuit Dkr is subtracted from the output signal of the adder Aj, and the subtraction result (pressure P.

- equivalent) is sent to the delay circuit Dkr. Also, subtractor A
, the output signal (pressure P, 10 phases'1) of the delay circuit D+ar is subtracted from the output signal of the adder Aj, and the subtraction result (corresponding to pressure Pr) is sent to the delay circuit Dd. , Furthermore, in the subtraction PJ A, the output signal (pressure P, equivalent to 10) of the delay circuit DTH is subtracted from the output signal of j to the adder, and the subtraction result (pressure P, equivalent to -) is sent to the delay circuit DTH. H,
sent to.

Then, the signal input to the delay circuit DTH is delayed for a predetermined time and input to the low-pass filter L P F T H, and an acoustic loss at the tone hole opening is added to the signal. Then, the output signal of the low-pass filter LPFTH is multiplied by the reflection coefficient the for the air pressure wave at the opening of the tone hole TH by a multiplier M4.

This reflection coefficient the is determined by the musical tone control circuit 100 when a musical tone is generated.
The tone hole T I-
When 1 is in a closed state, it is switched to a positive value, and when it is in an open state, it is switched to a negative value. In addition, this musical tone synthesizer can control the resonant circuit 3 by using an operator such as a volume (not shown), for example.
It is now possible to specify the Q height of the 0 resonance. Then, the amount of operation of this operator is determined by the tone control circuit 1.
00 is detected, and the value of the reflection coefficient the when the tone hole TH is in an open state is variably controlled according to the amount of operation. More specifically, when lowering the resonance Q of the resonant circuit 30, the absolute value of the reflection coefficient the is adjusted to a small value, and when increasing Q, the absolute value of the reflection coefficient the is adjusted to a large value. .

Note that the relationship between the reflection coefficient the and Q will be explained in detail later.

The multiplication result of the multiplier M4 is then delayed by the delay circuit DTH and input to the subtracter A and the multiplier M3. delay circuits DTH, and D'rH;

The delay time is equal to the height of the tone hole TH, that is, the time required for the air pressure wave to travel back and forth across the cylindrical portion of the tone hole TH. In this way, the propagation of the air pressure wave at the point j near the tone hole TH described above is simulated.

The Junkshijin J RTC is provided to calculate the scattering of air pressure waves of the resistor tube RTC.

Here, each multiplication coefficient is b□b is each diameter φ+b, φ, b corresponding to the resistor tube RTC.

It is determined based on φ and b. In addition, LPFRTC is a low-pass filter that provides acoustic loss when the resistor tube RTC is open, DRTC, and DRTC! is a delay circuit having a delay time depending on the height of the resistor tube RTC. Also, the reflection coefficient rtc is the resistor tube RT
It can be switched according to the opening and closing of C. The structure of Jangfusijin J RTC is Jangfusibon JTI-1.
are exactly the same, and the only difference is in each coefficient used in the calculation, as explained above. Therefore, a detailed description of the configuration regarding the junction JRTC will be omitted.

Now, the delay circuit Djr in this musical tone synthesizer.

D jr, D kf, D kr, D mf, D
Each of the sr's has a number of stages of delay elements, and is configured to be able to switch and control the number of stages of delay elements that contribute to signal delay. Then, the delay stage number data e1 is given to the delay circuits Djf and Djr, the delay stage number datum is given to the delay circuits Dkf and Dkr, and the delay stage number data m is given to the delay circuits DllIr and Dmr from the tone control circuit 100, and the circuits are opened. The distribution of these delay times can be switched depending on the position of the tone hole TH. In addition, as a specific circuit of this type of delay circuit that can control the delay time, for example, an input signal is input to a shift register driven by a shift clock of a predetermined cycle, and a desired one of the outputs of each stage of the shift register is input. It is possible to use a method in which a selector or the like selects and outputs one corresponding to the delay time.

Here, the control of the distribution of delay time corresponding to the above-mentioned opening/closing operation of the tunnel hole will be described in detail. Now, it is assumed that the tone hole TH in FIG. 2 is in an open state among the many tone holes provided in the resonance tube 1, and is the tone hole closest to the lead 2a. In this case, the delay stage number data Q1 and Q are such that the sum of both data is equal to the delay stage number n corresponding to the distance from the lead 28 to the tone hole TH, and the ratio of the delay stage number Q to the delay stage number n is set to a constant value. Note that the relationship between the number of delay stages Ql and the number of delay stages n will be described later.

Furthermore, when the number of delay stages corresponding to the total length of the resonance tube l is e8, the stage number data 5 = 12s-n is the delay circuit I) sr.
and Dsr. In this way, the delay time of each delay circuit is set. And Junk Shin J
The coefficients a, oH+atorr, and aso[ are supplied to TH, and -1 is supplied as the reflection coefficient the. On the other hand, if you cover all the tone holes with your fingers,
Stage number data n and m are determined corresponding to the tone hole position closest to the terminal end IE.

The junction JTH has coefficients alOn, a
*011 r a @ Ofl is supplied, and l is supplied as the reflection coefficient the. In addition, it supports opening and closing operations of resistor tube RTC, and junction J
The reflection coefficient rtc in the RTC and the multiplication coefficients b+, b□b for product-sum calculations are switched.

A musical tone synthesizer having the configuration shown in FIG. 1 as described above was fabricated as a prototype, and the musical sound waveform was evaluated. Below, we will list and explain each parameter that was set for the prototype in this evaluation.

List of design parameters> [Filters] ◇Low pass filter for tone hole TH LPFT H (
D h t) t 7 frequency fcTI+=2500
[Hz] ◇Low pass filter for resistor tube RTC L P F RTC cutoff frequency fcRTc=
7000 [)1 z]◇Cutoff frequency fcML of low-pass filter ML for final GW section IE = 200
0 [Hz] ◇Cutoff frequency rcdcf of filter 13 (low-pass filter) = 1500 [Hz] [Number of stages of delay circuit (number of shift register stages)] ◇Delay circuit D
jr, D kr and Dmf (delay circuit Djr.

Total number of delay stages of delay circuits Djr and D kr (corresponding to the total length of resonance tube l) h = 82 n = 40 ◇Number of delay stages of delay circuit Djf (delay circuit Dir) (corresponds to the distance from lead 2a to resistor tube RTC)
e, = 10 ◇Number of delay stages in each of the delay circuits DTH and DTH (
Corresponding to the height of tone hole TH) ffT11 = 1 ◇ Number of delay stages of each of delay circuits DRTCI and DRTCI (
Corresponding to the height of the resistor tube RTC) 12RTC=
2 [Tone hole TH related parameters] φ, = 24
[Question] φ== 24 [s+m] φ,=16 [帥] Based on these various values, calculate the above multiplication coefficient a+ofr,
Calculate aloft and a3off, and connect junction J
It was set to TH.

[Resistor tube RTC related parameters] φ,
b= 1 9 [mml φ, b= 19 [Question] φ-b-3 [s+*] Calculate the above multiplication coefficient based on these various values.

off, bsofr, bsofr, bton,
Calculate byon, bson, junk silan J R
I set it to TC.

Further, the reflection coefficient rLc was switched to two types: 1 (resistor tube RTC closed state) and -1 (resistor tube RTC open state).

[Other parameters] ◇Multiplication coefficient of inversion circuit rv (reflection coefficient of terminal part IE) γ
= -0,9 ◇Multiplication coefficient of multiplication 117 (impedance to air flow of resonance tube l) G = 0.3 Then, with each of the above parameters set, the reflection coefficient the in the junk signal J'TH is set to various values. The musical tone synthesizer shown in Fig. 1 was evaluated. In this evaluation, we separated the excitation circuit 10 from the musical tone synthesizer shown in Fig. 1, inputted an impulse from a point, observed the response at a point t, and applied the FF to the impulse response.
Applying T (fast Fourier transformation PI&), Fig. 3(a),
The transmission amount frequency characteristics shown in (b) were obtained. Note that FIG. 3(a) shows the case where the reflection coefficient rtc for the resistor tube RTC is set to 1, and FIG. 3(b) shows the case when rLc='-1. As shown in these figures, the reflection coefficient the in the tone hole T H is -1, -0,
It can be seen that as the absolute value becomes smaller, such as 9, -0, 8, the resonance Q at each resonance frequency becomes smaller (that is, the bandwidth becomes wider).

In this musical tone synthesizer, as described above, the value of the reflection coefficient the when the tone hole TH is open can be changed by operating the operator, and as can be understood from the above evaluation results, the resonance of the resonant circuit 30 can be changed. Q can be adjusted. Therefore, it is possible to perform flexible performance control such as changing the order of the main resonance frequency of a musical tone during performance, and also to perform a variety of timbre control.

In addition, in the above example, by reducing the absolute value of the reflection coefficient the in junk silane JTH,
Although the Q of the resonant circuit 30 is controlled, for example, the delay circuit excitation circuit D nr, D air, D sr,
D nr, D ir, D kL D kr, D
The same effect as in the above embodiment can be obtained by inserting a signal attenuation multiplier before or after jr and controlling the attenuation rate.

In addition, in the above-mentioned embodiment, the case where the delay time of the traveling wave and the delay time of the reflected wave were made equal was explained, but the signal output from the excitation circuit 10 is
If the total amount of time until the signal is fed back to the excitation circuit IO via C, JTH, or termination circuit TRM is constant, even if the delay time for the traveling wave and the delay time for the reflected wave are distributed unbalanced. I do not care.

"Effects of the Invention" As explained above, according to the present invention, there are provided a plurality of signal processing means for performing predetermined signal processing on each forward and reverse input signal and outputting the resultant signal, and each of the signal processing means. means for connecting the signal processing means, the means for performing predetermined arithmetic processing on the output signal of each connected signal processing means, and supplying the result of the arithmetic operation to the signal processing means as an input signal. a resonant circuit constituted by a signal scattering junction, and excitation means that generates an excitation signal based on an input signal to itself and a feedback signal from the resonant circuit, and inputs the excitation signal to the resonant circuit. , a signal attenuation means is inserted in a transmission path until the excitation signal outputted from the excitation means is fed back to the excitation means via the resonant circuit, and the amount of signal attenuation in the signal attenuation means is controlled. Therefore, it is possible to control the resonance Q of the resonant circuit, and it is possible to achieve the effect that flexible performance control can be performed.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of a musical tone synthesizer according to an embodiment of the present invention, FIG. 2 is a diagram showing a physical model of a clarinet simulated by the embodiment, and FIG. 3 is a t+, FIG. 3 is a diagram showing transmission amount frequency characteristics when looking at the resonant circuit 30 side from point Lm. JTH・・・Junk thin for tone hole, J
RTC・・・Junk thin for resistor tube, Dnr, D+ar, Dmr, Dnr, Djf, Dkf
, Dkr, Dj+”-=delay circuit, 100...
Musical tone control circuit.

Claims (1)

[Scope of Claims] A plurality of signal processing means for performing predetermined signal processing on each input signal in both forward and reverse directions and outputting the resultant signal, and means for connecting each of the signal processing means; a resonant circuit constituted by at least one signal scattering junction that performs predetermined arithmetic processing on the output signal of each signal processing means and supplies the result of the arithmetic operation to the signal processing means as an input signal; excitation means for generating an excitation signal based on an input signal and a feedback signal from the resonant circuit and inputting the excitation signal to the resonant circuit, the excitation signal output from the excitation means being transmitted through the resonant circuit; A musical tone synthesis device characterized in that a signal attenuation means is inserted in a transmission path from the signal to the excitation means, and the amount of signal attenuation in the signal attenuation means is controlled.