JPH0365994A - Musical sound synthesizer - Google Patents

Abstract

PURPOSE:To synthesize a musical sound faithful to the harmonic structure of an actual wind instrument sound by suppressing the resonating operation of the two-way signal transmission line from an exciting means which generates an exciting signal according to an input signal and the feedback signal from a resonance circuit to a terminal processing means which controls an attenuation coefficient. CONSTITUTION:A signal scatter junction 20 which is interposed and connected between stages corresponding to sound holes of a resonance pipe and performs specific arithmetic processing for each input signal supplied to itself to output the resulting signal to a two-way signal processing means, and the resonance circuit 30 attenuates the output signal of the two-way signal processing means and supplies it to the two-way signal processing means. further, the exciting means 10 inputs the exciting signal to the resonance circuit according to the input signal and the feedback signal from the resonance circuit and the terminal processing control means 100 controls the attenuation coefficient of the terminal processing means TRM corresponding to the opening/ closing operating of the sound holes. Consequently, the musical sound which is faithful to the spectrum of the actual wind instrument sound can be generated.

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 synthesis before a wind instrument.

"Prior Art" A method is known in which a model obtained by simulating the sound generation mechanism of a natural musical instrument is operated, thereby synthesizing the musical tones of a natural musical instrument. The most basic model of a wind instrument such as a clarinet is a model with a closed-loop structure in which a nonlinear amplification element that simulates the elastic characteristics of a reed and a resonant circuit that simulates a resonant tube are connected. 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 the feedback signal from the resonant circuit, that is, the signal corresponding to the reflected wave from the resonant tube, is nonlinearly amplified. It is fed back to the element. In this way, the propagation of air pressure waves in a wind instrument is faithfully simulated by a closed loop circuit consisting of a nonlinear amplification element and a 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 configuration that has multiple bidirectional transmission circuits and a circuit called a signal scattering junkijin (hereinafter abbreviated as junkijin) that performs signal processing corresponding to tone holes between each bidirectional transmission circuit. A resonant circuit is used.

In each junksign, calculation processing such as coefficient multiplication is performed on each input signal from an adjacent bidirectional transmission circuit, and the calculation result is 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 addition, the traveling wave signal output from the bidirectional transmission circuit corresponding to the end of the resonant tube is subjected to a filter operation that simulates acoustic loss at the end of the resonant tube, and is multiplied by a reflection coefficient. The signal is again input to the bidirectional transmission circuit and fed back to the nonlinear amplification element side.

According to such a configuration, the multiplication coefficient for calculation at each junction is switched in accordance with the open/closed state of the tone hole concerned, the scattering state of the signal within the resonant circuit changes, and the transmission amount frequency characteristics of the resonant circuit are changed. can be switched. Accordingly, a musical tone having a pitch corresponding to the opening/closing operation of the tone hole is generated. Note that this type of technology is known, for example, from Japanese Patent Application Laid-open No. 1983
〇 “Problems to be Solved by the Invention” Disclosed in Publication No. 40199 By the way, when actually playing a wind instrument, the resonance mode IJ occurs in the propagation path of the air pressure wave between the reed and the open tone hole. A fundamental wave (first order) with a frequency that is dominant and corresponds to the propagation delay in this path, and overtones of each frequency (higher order) that is an integral multiple of the fundamental wave are mainly generated as musical tones. However, in the case of the conventional musical tone synthesizer described above, even when each multiplication coefficient of the junk signal is set to a value corresponding to the state where the tone hole is open, both sides from the nonlinear amplification element to the final stage bidirectional transmission circuit are There is a problem in that a considerable proportion of the frequency components generated by the resonance of the direction signal transmission path are included in the musical tone, resulting in a synthesized musical tone with a spectrum different from that of the actual wind instrument sound.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to provide a musical tone synthesis device capable of suppressing the generation of unnecessary resonance frequency components and synthesizing musical tones that are faithful to the overtone structure of actual wind instrument sounds. With the goal.

"Means for Solving the Problems" In order to solve the above problems, the present invention provides means for simulating a resonant pipe of a wind instrument, which (a) performs predetermined signal processing on input signals in forward and reverse directions; (b) a plurality of bidirectional signal processing means corresponding to the sound holes of the resonant tube and connected between each stage of the bidirectional signal processing means to output each input signal to itself; (c) a signal scattering junk signal that performs predetermined arithmetic processing on the signal and outputs the arithmetic result as an input signal to the bidirectional signal processing means; The termination processing means is connected to the bidirectional signal means corresponding to the termination section, and is configured by a termination processing means that performs at least attenuation processing on the output signal from the bidirectional signal processing means and supplies the output signal to the bidirectional signal processing means as an input signal. a resonant circuit that corresponds to the opening/closing operation of the sound hole, and a pitch control means that controls a coefficient for calculation in the signal scattering circuit; and means that simulates the operation of the reed of the wind instrument, excitation means for generating an excitation signal based on an input signal to itself and a feedback signal from the resonant circuit and inputting the excitation signal to the resonant circuit; and a termination processing control means for controlling the attenuation coefficient in the attenuation processing.

"Operation" According to the above configuration, the resonant operation in the bidirectional signal transmission path from the excitation means to the termination processing means, that is, from the lead to the termination part of the resonance tube is suppressed.

"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. Furthermore, FIG. 2 is a diagram showing the configuration of a physical model of a clarine throat that is simulated by this musical tone synthesizer.

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

In FIG. 2, 1 is a resonance tube (tube section) of a wind instrument, 2 is a mouthpiece section, 2a is a reed, TH is one tone hole formed in the resonance tube 1, and RTC is a 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 vibrates due to the blowing pressure P and its own elastic properties (arrow 2S). As a result, an air pressure wave (compression wave) is generated inside the tube of the reed 2a, and this becomes a traveling pressure wave F and reaches the terminal end IE of the resonance tube l.
sent towards. Then, the traveling pressure wave F is reflected at various places in the resonance tube I and at the terminal end IH, 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, the total pressure PA that the reed 2a receives during blowing is equal to the pressure of the reflected pressure wave R.
If R, then PA=P=-PR (1), and as a result, the reed 2a vibrates due to its own elastic properties and the pressure PA. 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 musical sound force.

The first-order resonance frequency at this time is the resonance tube l! Switching is performed by opening and closing two tone holes TH. That is, when the tone hole T)I is opened/closed, the flow of pressure waves near the tone hole TH changes accordingly, and the effective length of the resonant tube l changes, thereby changing the resonant frequency. will be done.

Hereinafter, the state of the air pressure wave at a point j near the tone hole TH 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+oHp, + + asorr p, +
aaoN Ps+ (2). Here, P, + is the pressure of the air pressure wave flowing into the point j from the lead 2a side of the resonance tube 1, pm++; is the pressure of the air pressure wave flowing into the point j from the end IE side of the resonance tube 1, and , P, now indicates the pressure of the air pressure wave flowing from the tone hole TH. In addition, a+orr*a, oH, and asorr are coefficients corresponding to the contribution of each air pressure wave flowing into point j to the air pressure Pj at point j, and are expressed by the equation 1 (3
) to (5).

alorr= 2φ,'/(φ1'+φ1+φ1〉・
・・・・・・(3〉a*orr= 2φ1/(φ18+φ
e+φ3') ・・・・・・(4) asorr=2φ
S'/(φI'+φ1+φs') (5) Here, φ1 is the diameter of the resonant tube l on the lead 2a side, φ
, represents the diameter of the end IE side of the resonance tube l, and φ represents the diameter of the tone hole TH.

On the other hand, in FIG. 2, from point j to lead 2a of resonance tube l
The pressure of the air pressure wave flowing out in the direction P1-5, the pressure P of the air pressure wave flowing out in the direction of the terminal end IE of the resonance tube l, and the pressure of the air pressure wave flowing out into the tone hole TH, Ps-
Then, these are each P r-” P j-P 1
+ ・・・・・・(6)P *-= P j-P-・
...(7) Ps-=Pj-P, +...
・(8) becomes.

The air pressure wave (pressure P t-) propagating from point j to the terminal end IE eventually reaches the terminal end IE and is partly reflected toward the reed 2a, but when the terminal end is In the case of open wind instruments, a phase inversion takes place during this reflection. Also, when the tone hole T H is open, j
The air pressure wave (pressure P, -) flowing out from the point to 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 becomes 0. Therefore, the above formula (3)
By substituting φ, = 0 into ~(5), the air pressure P of each air pressure wave when the tone hole TH is in the closed state is obtained.
Coefficient a + On + 11 corresponding to the contribution to 3
*On 1 a s On is represented by the following formula (9) ~ (1
1).

a, on = 2φ, snow/(φI′+φ,”) ・−・
...(9) amon=2φ1/(φ♂1φ,”)
・・・−・(l 0)a-on= 0
-...(11) Then, the air pressure Pj at point j is Pj"aIONPr" + axon
P! ＋ ason P s＋・・・・・・(12
) becomes.

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 open, 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 characteristics of the resonance tube l in this case are the first-order resonance frequency,
It has a multimodal characteristic in which the transmission gain becomes maximum at high-order resonance frequencies of 3 times, 5 times, . . . .

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, but the resistor tube RTC is provided to promote resonance at a high-order resonance frequency in the resonance tube 1. 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 4,
At points near the resistor table RTC, scattering of air pressure waves occurs. Q l ”r Q t ”+ 03+
is the pressure of the air pressure wave flowing into the neighboring point k, Q,−,Ql
,Q,- is the pressure of the air pressure wave flowing out from the neighboring point k. When the resistor tube RTC is in a closed state, the components of the air pressure wave that are returned to the lead 2a are dominated by those that are reflected back at the tone hole TH or the terminal end 1E. On the other hand, when the resistor tube RTC is in an open state, the scattering of the air pressure wave at the resistor tube RTC becomes significant, so that the component reflected at the resistor tube RTC is emphasized in the air pressure wave fed back to the lead 2a. Note that the scattering of the air pressure wave at this point k is caused by the scattering of the air pressure wave at the point j near the tone hole TH mentioned above.
Since this is the same as the case in , the detailed explanation here 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. Further, the junk silane 20 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 l.

In this junk silane 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. 19 and input to the excitation circuit 10.

The excitation circuit 10 includes a subtracter 11, filters 12 and 13
, adder 14, ROM 15, multiplication gain 16.17 and I
It consists of NV. 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. The subtracter 2 includes a junction 20 from the resonant circuit 30.
a signal inputted via the , that is, a signal corresponding to the air pressure PR of the reflected wave R from the resonance tube l in FIG. 2;
A signal corresponding to the blowing pressure P is input. Then, the above formula (1) is calculated, and the air pressure PA applied to the lead 2a is
A signal corresponding to is obtained.

The output signal of subtractor ll is band limited by filter [2]. This filter 12 is constituted by a first-order low-pass filter, and is inserted in order to prevent the vibration of the signal circulating between the excitation circuit 10 and the resonant circuit 30 from becoming significantly large at a specific frequency. The output signal Pl of the filter 12 is input to the filter 13 and is inverted by the multiplier INV.
6 is input. The signal Pl passes through the filter 13 to remove high frequency components. This simulates the response characteristics of the road 2a that absorbs sudden pressure changes.

Then, the adder 14 adds a signal corresponding to the embouchure E to the output signal Pl of the filter 13 to obtain a signal P3 corresponding to the pressure actually applied to the lead. This signal Pl 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 F corresponding to the flow velocity of air passing through the line between the reed 2a and the mouthpiece portion 2 is obtained.

And multiplication for signal FL? 317 by a multiplication coefficient G. Here, the multiplication coefficient G is a constant determined according to the diameter of the tube near the attachment point of the mouthpiece section 2 in the resonance tube 1, and corresponds to the difficulty of passing the airflow, that is, the impedance to the airflow. It is something to do. Multiply 117 therefore yields a signal corresponding to the air pressure change occurring at the mouthpiece-side inlet of resonance tube l. And this signal is Junction 2
0 to the resonant circuit 30.

In the resonant circuit 30, delay circuits D 3r and D kf
, Dmr, D + *r+ D kr, and D jr each correspond to the propagation path of the air pressure wave in 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 Dj' and D3r, the propagation delay between the resistor tube RTC and the tone hole TH is simulated by the delay circuits Dkf and Dkr, The propagation delay between T H and the termination lE is simulated by delay circuits D+mf and D+ar.

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, and then multiplied? :jrI V is multiplied by a negative reflection coefficient γ and returned to the resonant circuit 30. In this way, the frequency characteristics of the acoustic loss at the termination IE and the phase inversion associated with reflection are simulated.

Now, with the reflection coefficient γ adjusted to a constant value so that the musical tone when the tone hole TH is closed is faithfully synthesized,
If a musical tone is generated when the tone hole TH is opened by switching each multiplication coefficient (described later) of the junction JTH, the reflected wave from the termination circuit TRM is fed back to the excitation circuit 10 at a level higher than the actual level, and is generated. The spectrum of the musical sound produced by the clarinet may differ from the actual clarinet sound. Therefore, in this musical tone synthesizer, the musical tone control circuit 100 controls the tone hole T.
The magnitude of the reflection coefficient γ is switched depending on whether the tone hole TH is closed or the tone hole TH is open.

Note that the relationship between the magnitude of the reflection coefficient γ and the spectrum of musical tones will be described later.

The junction JTH in the resonant circuit 30 is obtained by simulating the scattering of the air pressure wave at a point j near the tone hole TH in FIG.
1 multiplication PJM,, M□M,, M subtraction W A +, A
□A s-delay circuit DTH, , DTH1, cl-pass filter LPFTH. The adder Aj receives the output signal of the delay circuit Dkf (corresponding to pressure P, 10 in Fig. 2).
is multiplied by a coefficient a by a multiplier M, a signal obtained by multiplying the output signal of the delay circuit DIIlr (corresponding to the pressure P1+ in FIG. 2) by a coefficient at by a multiplier M, and the output of the delay circuit DTH. Signal (corresponds to pressure P, 10 in Figure 2)
A signal obtained by multiplying by a coefficient 83 by a multiplier M3 is input. In addition, each coefficient al, a□a, when the tone hole TH is open, the tone control circuit 100
from the coefficient alo[, aa according to the above equations (3) to (5)
on, asorf is given, and the tone hole TH
When is in a closed state, coefficients a+On+ amon and aaon are given according to the above equations (9) to (11).

Then, the addition result of adder Aj, that is, the signal corresponding to the air pressure Pj at point j, is subtracted by subtractor 1, A.

and A, are input. Then, in subtraction R3A, the output signal of the delay circuit Dkr (pressure P, equivalent to 10) is subtracted from the output signal of the adder Aj, and the subtraction result (pressure P.

corresponding) is sent to the delay circuit Dkr. Also, subtractor A,
Then, the output signal of the delay circuit Dar (pressure P, equivalent to 10) is subtracted from the output signal of the adder Aj, and the subtraction result (pressure P1
corresponding) is sent to the delay circuit Dmf. Furthermore, subtractor A
, the output signal (pressure P, equivalent to 10) of the delay circuit DTH, is subtracted from the output signal of the adder Aj, and the subtraction result (pressure P, equivalent to -) is sent to the delay circuit DTH,.

The signal input to the delay circuit DTH is delayed for a predetermined time and then input to the low-pass filter L P F T H, and acoustic loss at the tone hole opening is added to the signal. Then, the output signal of the low-pass filter LPF T H is multiplied by the reflection coefficient the for the air pressure wave at the opening of the tone hole T I-1' by the multiplication LI M.

The multiplication result of the multiplier M4 is then delayed by the delay circuit DTH and input to the subtractor A and the multiplier M. The delay times of the delay circuits DTH and D T +-11 are 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.

Junction J RTC is provided to calculate scattering of air pressure waves of resistor tube RTC.

Here, each multiplication coefficient S, b□b is determined based on each diameter φlb, φtb+φsb corresponding to the resistor tube RTC. In addition, LPFRTC is a low-pass filter that provides acoustic loss when the resistor tube RTC is open, and DRTC and DRTCl are the resistor tube RT
This is a delay circuit having a delay time depending on the height of C. Further, the reflection coefficient rta is switched corresponding to opening and closing of the resistor tube RTC. In addition, Junk Silan J RT
The configuration of C is exactly the same as junction JTH,
As explained above, the only difference is in each coefficient used in the calculation. 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 kr, D kr, D aL 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. The musical tone control circuit 100 provides delay stage number data QI to delay circuits Djf and Djr, delay stage number data Q to delay circuits Dkr and Dkr, and delay stage number data m to delay circuits Dmf and Dar, The distribution of these delay times can be switched depending on the position of the tone hole opening (2) to be opened. 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, and Q, are the sum of both data, which is the delay stage number n corresponding to the distance from the lead 2a to the tone hole TH.
and the ratio 7 of the number of delay stages 121 to the number n of delay stages is set to a constant value.The relationship between the number of delay stages a and the number n of delay stages will be described later. When the number of delay stages corresponding to the total length of pipe l is Qs, the stage number data base of ta=(Is-n) is the delay circuit D.
sf and DIIlr. In this way,
The delay time of each delay circuit is set. Then, the coefficient aIoft, a, oH, as
orr is supplied, and -1 is supplied as the reflection coefficient the. On the other hand, when all the tone holes are covered with fingers, the stage number data n and m are determined corresponding to the tone hole position closest to the terminal end lE.

Then, the coefficient a+on+
amon, asofl are supplied and the reflection coefficient L
1 is supplied as hc. Also, resistor tube R
Corresponding to the opening/closing operation of the TC, the reflection coefficient rtc and the multiplication coefficient b1 for sum-of-products calculation in the Junxin J RTC are
+bt+bt is 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 T H LPF711
Cutoff frequency rcT11 = 2500 [Hzl
◇Low pass filter LP for resistor tube RTC
F RTC cutoff frequency fcRTc = 7000
[Hz] ◇Cutoff frequency rcML of low-pass filter ML for final i section tc = 2000 [Hz] ◇Cutoff frequency rcdcr of filter 13 (low-pass filter) = 1
500 [Hz] [Number of delay circuit stages (number of shift register stages)] ◇Delay circuits D jl, D kr and D+sf
(Delay circuit Djr.

Dkr and D sr) (corresponds to the total length of resonance tube l) 12g = 82 ◇Total number of delay stages (distance from lead 2a to tone hole position) of delay circuits Djf and Dkf (delay circuits Djr and Dkr) ) n = 40 ◇Number of delay stages of delay circuit Djr (corresponds to the distance from lead 2a to 2-stage static tube RTC) 12. = 10 ◇Number of delay stages in each of the delay circuits DTH and DTH (
Corresponding to the height of tone hole TH MT11 = 1◇Delay circuit DRTC, and DRTC! Number of delay stages for each (corresponds to the height of resistor tube RTC) QRTc = 2 [Tonehole TH related parameters] φ, = 24
[Open] φ, = 24 [all φ−”” 16 [ms] Based on these various values, the multiplication coefficient a+orr,
Compute atorL asorf and junk thin JT
It was set to H.

Further, the number of the reflector was set to -1 (tone hole TH open state).

[Resistor tube RTC related parameters] φ1b
=19 [1IIl] φ, 1) == t 9 [Ko] φ sb= 3 [-Peng] The above multiplication coefficient is calculated based on these various values.

Off, h! art, baorr, b+on+
Calculate bmon + bson, Junxylon J R
I set it to TC.

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

[Other parameters] ◇ Multiplying coefficient of multiplier 17 (impedance to air flow of resonance tube l) G = 0.3 Then, with each of the above parameters set, the reflection coefficient γ supplied to the termination circuit TRM is adjusted to various values. Switch to the value of
The musical tone synthesizer shown in Fig. 1 was evaluated. In this evaluation, the excitation circuit 10 was separated from the musical tone synthesizer shown in FIG.
An impulse is input from point t, the response is observed at point t, and FFT (fast Fourier transform) is applied to the impulse response to obtain the transmission frequency shown in Fig. 3(a) and (b). Obtained characteristics. 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 rtc=1.

The transmission amount frequency characteristics between points t and -Lm are the spectrum of resonance in the path from point t to point t via junction JTH, that is, the path between lead 2a and tone hole TH, and the point From tl to termination circuit TRM
The route to point t through , that is, lead 2a
and the spectrum of resonance in the path between the terminal end IE of the resonant tube I. Figure 3(a),
Each of the resonance peaks centered on the resonance frequencies rt and r in (b) is a spectrum of resonance between the lead 2a and the terminal end IE of the resonance tube l. As shown in these figures, the reflection coefficient γ in the termination circuit 712M is set to -1, -
By reducing the absolute value such as 0.9° - 0.8, the gain at the resonant frequencies r, , r can be reduced.

In this musical tone synthesizer, as mentioned above, the tone hole T
The value of the reflection coefficient γ is changed in response to the opening/closing operation of H, and as can be understood from the above evaluation results, the intensity of the resonance spectrum between the lead 2a and the terminal end 18 is changed.
1M can be adjusted.

Therefore, unnecessary spectrum can be suppressed and musical tones faithful to the four tones of actual wind music can be produced.

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 excitation circuit! The signal output from J f
l '1'' C or J T r- [or if the sum of the times until it is fed back to the excitation circuit !0 via the termination circuit TrlM is constant, the delay time for progressive fatigue and the delay time for reflected waves. It does not matter if the distribution is unequal.

"Effects of the Invention" As explained above, according to the present invention, there is provided a means for simulating a resonant tube of a wind instrument, which (a) performs predetermined signal processing on input signals in each of the forward and reverse directions. a plurality of bidirectional signal processing means, each outputting a plurality of bidirectional signal processing means; a signal scattering junction that performs predetermined arithmetic processing and outputs the arithmetic result as an input signal to the bidirectional signal processing means; and (c) corresponds to the terminal end of the resonance tube in each of the bidirectional signal processing means. a resonant circuit configured by a termination processing means connected to a bidirectional signal processing means, which performs at least attenuation processing on an output signal from the bidirectional signal processing means and supplies the output signal as an input signal to the bidirectional signal processing means; , a pitch control means that corresponds to the opening/closing operation of the tone hole and controls a calculation coefficient at the signal scattering junction, and a means that simulates the operation of the reed of the wind instrument 2g, which inputs to itself. excitation means for generating an excitation signal based on the signal and a feedback signal from the resonant circuit and inputting the excitation signal to the resonant circuit; Since a termination processing control means for controlling the attenuation coefficient is provided,
The effect is that unnecessary spectrum can be suppressed, and musical tones can be generated that are faithful to the spectrum in front of the actual wind instrument.

[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 diagram showing the L+, FIG. 4 is a diagram showing transmission amount frequency characteristics when looking at the resonant circuit 30 side from point Lx. JTH...Tone hole junction, JRTC...Resistor tube junction, DnL D d, D tar, D ir,
D jf, D kr, D kr, D jr---
-Delay circuit, 100... musical tone control circuit.

Claims (1)

[Scope of Claims] A means for simulating a resonant tube of a wind instrument, comprising: (a) a plurality of bidirectional signal processing means for performing predetermined signal processing on input signals in each of the forward and reverse directions and outputting the resultant signals; (b) corresponds to the sound hole of the resonance tube, is inserted and connected between each stage of each of the two-way signal processing means, performs predetermined arithmetic processing on each input signal to itself, and outputs the result of the arithmetic operation; a signal scattering junction outputting as an input signal to the bidirectional signal processing means; and (c) connected to bidirectional signal means corresponding to the terminal end of the resonant tube in each of the bidirectional signal processing means; a resonant circuit configured by a termination processing means that performs at least an attenuation process on an output signal from the bidirectional signal processing means and supplies it as an input signal to the bidirectional signal processing means; pitch control means for controlling calculation coefficients at the signal scattering junction; and means for simulating the operation of the reed of the wind instrument, the means for exciting based on an input signal to itself and a feedback signal from the resonant circuit. An excitation unit that generates a signal and inputs the excitation signal to the resonant circuit; and a termination control unit that corresponds to the opening/closing operation of the sound hole and controls a damping coefficient in the attenuation process of the termination unit. A musical tone synthesis device characterized by the following.