JPH02280197A - Musical tone synthesizer - Google Patents

Abstract

PURPOSE:To allow the exact simulation of a wind instrument, sound field, etc., and the synthesis of real musical tones by providing a 3rd signal processing means which simulates the tone holes having build-ups. CONSTITUTION:This synthesizer has the 1st to 3rd signal processing means which output signals by delaying respective input signals for the prescribed time and a coupling means. Musical tone signals are generated by putting the 1st to 3rd signal processing means and the coupling means into a resonance state. The 3rd signal processing means assumes the build-up part of the tone holes and the 1st and 2nd signal processing means assume respectively the resonance tube on a lead side and the resonance tube on a terminal side. The 1st to 3rd signal processing means are coupled by the coupling means. The exact simulation of the wind instrument and the synthesis of the real musical tones are executed in this way.

Description

DETAILED DESCRIPTION OF THE INVENTION "Field of Industrial Application" The present invention particularly relates to a musical tone synthesis device suitable for use in electronic wind instruments.

"Prior Art" A method is known in which a model obtained by simulating the sound production mechanism of a natural musical instrument is operated, thereby synthesizing the musical tones of a natural musical instrument. This kind of technology is
For example, it is disclosed in Japanese Patent Application Laid-Open No. 63-40199. Hereinafter, using a wind instrument as an example, a model of its sound production mechanism will be explained, and then a musical tone synthesis device using this model will be explained.

FIG. 6 shows a schematic structure of a wind instrument such as a clarinet or saxophone. In the figure, ■ indicates a resonance tube (tube section) of a wind instrument, 2 indicates a reed, and TH indicates a tone hole formed in the resonance tube 1 for controlling pitch.

In this configuration, when the player blows 2A of exhaled air into the reed 2, the reed 2 vibrates due to the expiratory pressure PA and its own elastic properties (arrow 2S). As a result, an air pressure wave (f11 dense wave) is generated inside the tube of the lead 2, which becomes a traveling pressure wave F and is sent toward the terminal end IE of the resonator 1. The traveling pressure wave F is reflected at various locations within the resonant tube I and at the terminal end tE, becomes a reflected pressure wave R, and returns to the lead 2, and the lead 2 receives the pressure PR from the reflected pressure wave R. Therefore, when the pressure of the reflected pressure wave R is PR, the total pressure P that the reed 2 receives while playing is as follows: P = PA - PR (1) After all, the reed 2 has its own elastic properties. and the above pressure P
It vibrates due to Then, the vibration of reed 2 and the resonance tube l
A musical tone is generated when the reciprocating motion of the pressure waves F and R within resonates.

The resonance frequency at this time is switched by opening and closing the tone hole TH formed in the resonance tube I. 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 l changes, thereby switching the resonance frequency.

FIG. 7 shows an example of the configuration of a musical tone synthesis device obtained by simulating the sound generation mechanism of a wind instrument as described above. In the figure, 11 is a nonlinear element that simulates the operation of lead 2, 12 is a resonance circuit that simulates resonance tube 2, and 13 is a subtracter that simulates the pressure calculation of equation (1) performed in lead 2. It is.

Here, the output signal of the nonlinear element 11 is input to the resonant circuit 12 as a traveling wave signal, and the output signal of the resonant circuit 12,
In other words, the reflected wave signal is a subtracter! 3 is set to be input.

In the resonant circuit I2, B D ,, B D ,...
・ is a bidirectional transmission circuit that simulates the transmission delay of air pressure waves propagating inside the resonant tube l. Moreover, each bidirectional transmission circuit B D ,, B D 1. In ..., D
F indicates a delay circuit for transmitting a traveling wave signal, and DR indicates a delay circuit for transmitting a reflected wave signal. TRM is a termination circuit that simulates the reflection of pressure waves at the termination end fE (FIG. 6) of the resonance tube l. Here, the termination circuit TRM is a low-pass filter ML that simulates acoustic loss due to reflection.
and an inversion circuit IV that simulates the phase inversion of the input signal that also occurs due to reflection. It should be noted that this inversion circuit I■ is necessary only when the terminal end IE is an open end, and is unnecessary when it is a closed end.

JU+ is a junction that simulates the scattering of pressure waves in the vicinity of the tone hole TH.

Here, M, , M2 are multipliers, AA is a subtracter, and Aj is an adder. The adder Aj includes a bidirectional transmission circuit BD,
The traveling wave signal from the multiplier M is multiplied by a coefficient 31 and input, and the reflected wave signal from the bidirectional transmission circuit B is inputted to the multiplier M after being multiplied by a coefficient a2. Signal addition is performed. Note that these coefficients a1 and a will be described later. and,
This addition result is sent from adder Aj to subtracters A1 and A2.
sent to. Then, in the subtracter A1, the traveling wave signal F, Lh<< is subtracted from the output signal of the adder Aj, and the subtraction result is set as the reflected wave signal R, which is transmitted to the bidirectional transmission circuit BD.

sent to. Further, the subtracter A subtracts the reflected wave signal R from the output signal of the adder Aj, and the subtraction result is sent as a traveling wave signal F to the bidirectional transmission circuit BD.

Here, the coefficients by which the signals Fl and R1 are multiplied will be explained.

<When the tone hole TH is open> At a point j near the tone hole TH in the resonance tube l in FIG. 6, the air pressure Pj at this point j is P j = a+
offP I++ atofr Pt+...”
(2) becomes. Here, P1+ is the pressure of the air pressure wave flowing from the lead 2 side of the resonance tube l to point j, and P,+ is the terminal end of the resonance tube l! It shows the pressure of the air pressure wave flowing from the E side to point j. Furthermore, atofT and atoff are coefficients indicating the distribution of the magnitude of each air pressure wave flowing into point j, and are given by the following equations (3) and (4).

a, off = 2φI′/(φ1′+φ2+φ3”)
−・・−(3) a=off'= 2φt'/(φ1'
+φ1+φ3ri...(4). here,
φ1 is the diameter of the resonant tube l on the lead 2 side, φ is the diameter of the terminal end IE side of the resonant tube I, and φ3 is the diameter of the tone hole TH. In FIG. 7, the traveling wave signal F1 corresponds to the pressure P1+, and the reflected wave signal R1 corresponds to the pressure P, 10.

Further, in this musical tone synthesizer, when the tone hole TH is in an open state, the coefficient a+o[I, atofT is the coefficient a
la, is applied to the multiplier M8,M. Therefore, the adder Aj outputs the calculation result of the above equation (2), that is, a signal corresponding to the air pressure Pj at the point j.

On the other hand, in Figure 6, from point j to the resonance tube! The pressure P of the air pressure wave flowing out in the direction of the board 2, -1 the terminal end of the resonance tube l! If the pressure of the air pressure wave flowing out in the E force direction is P, -, then these are respectively P+-=Pj-P++ (5) Py-=P
jPt+ (6). The signals corresponding to these pressures P, -, P, - are sent to subtractors A, ,
Output from At.

<When the tone hole TH is in a closed state> This case can be considered to be equivalent to a state in which the diameter φ3 of the tone hole TH becomes 0. Therefore, in the above equations (3) and (4), the following coefficient anon obtained by substituting φ, -〇,
anon adds adder A as coefficient a l + a t
+, given to A y.

a, on = 2φ,'/(φ1'+φ, ri...
(7) a2on=2φ2! /(φ2+φ,′) ・
...(8) And the resonance tube l according to the following formula (9)
A signal corresponding to the air pressure Pj at point j within is obtained from adder Aj.

P j=a+on P ,+ +ayon P x+
(9) Signals corresponding to the pressures P+- and Pt- are output from the subtracters A and A, respectively.

In this way, changes in the scattering state of air pressure waves within the resonance tube 1 corresponding to the opening/closing operations of the tone hole TH are simulated.

In this example of the musical tone synthesizer, a bias value VA corresponding to the blowing pressure PA is applied to the nonlinear element 11 via the subtracter 13. The output signal of the nonlinear element 11 is transmitted to the bidirectional transmission means B.
The signals are sent to the termination circuit TRM via D + , B D t , . . . and junk controllers JU + , . Here, junction JU
, . . ., the coefficient a l + a t is switched in response to the opening/closing operation of the corresponding tone hole TH as described above, and thereby the scattering state at the corresponding junction JU is switched. The traveling wave signal sent to the termination circuit TRM is processed by the low-pass filter ML and the inverting circuit ■V, and is converted into a reflected wave signal by the bidirectional transmission circuit BDn,..., BD t+BD, (where B
Dn indicates the bidirectional transmission circuit closest to the termination circuit TRM (not shown) and the junctions JU, . In this way, the nonlinear element II and the resonant circuit 12 enter a resonant state. The resonance frequency at this time is the coefficient a I+ 82 at each junction JU, ... corresponding to the opening and closing of the tone hole TH.
It can be switched by switching.

``Problem to be Solved by the Invention'' By the way, some actual wind instruments have tone holes that are raised, as shown in FIG. In this case, it is thought that there is a dispersion of pressure waves from the resonance tube to the opening of the tone hole, and a return of the pressure wave reflected at the opening of the tone hole to the resonance tube. The device does not take into account the prominence of the tone holes at all, and therefore has a problem in that it cannot accurately simulate an actual wind instrument.

The present invention has been made in view of the above-mentioned circumstances, and it is an object of the present invention to provide a musical tone synthesis device capable of simulating a tone hole with a raised tone.

"Means for Solving the Problem" A first invention provides first to third signal processing means each of which applies a predetermined delay time to an input signal and outputs the resultant signal; a coupling means for taking an output signal of the processing means as an input signal, performing predetermined arithmetic processing on these input signals and sending the result to the first to third signal processing means; A musical tone signal is generated by bringing the signal processing means and the coupling means into a resonant state.

Further, in a second invention, at least one of the first to third signal processing means in the first invention delays the input signal by a predetermined time and performs level control to output the signal. It is characterized by

Further, a third invention includes first and second signal processing means each delaying an input signal by a predetermined time and outputting the resultant signal, and a third signal processing means applying frequency band control to the input signal and outputting the resultant signal.
The outputs of the first to third signal processing means are used as input signals, and predetermined arithmetic processing is performed between these input signals. and coupling means for sending signals to the first to third signal processing means, and the musical tone signal is generated by bringing the first to third signal processing means and the coupling means into a resonant state.

Further, a fourth invention is characterized in that the third signal processing means in the third invention performs frequency band control and level control on the input signal and outputs the signal.

"Operation" In the above configuration, the third signal processing means is assumed to be a raised part of the tone hole, and the first and second signal processing means are assumed to be a resonant tube on the lead side and a resonant tube on the end side, respectively. This is what I did. By combining the first to third signal processing means using the combining means, it is possible to more accurately simulate a wind instrument.

"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. In this figure, the same reference numerals are given to the parts corresponding to those in FIG. 7 described above. In the figure, reference numeral 21 detects operations of various operators (not shown) equipped on the main body of the musical instrument, and accordingly musical tone control information (tone hole opening/closing signal, degree of blowing strength, note-on, note-o), etc. ) is a musical tone control information generating circuit that generates. 22 is an excitation circuit, for example, the nonlinear element shown in FIG. 7 mentioned above! 1 and a subtracter 13. Here, the excitation circuit 22 is supplied with a value VA according to information indicating the strength of the blowing performance supplied from the musical tone control information generation circuit 21.

JA is a junction corresponding to one tone hole, and 23 is a junction J according to the tone hole opening/closing signal.
This is a tonehole control circuit that controls coefficients for signal calculation processing in Al. Here, the tone hole control circuit 23 has a built-in coefficient calculation circuit shown in FIG. In FIG. 4, M, M l f + M + 3
indicates a multiplier, A indicates an adder, and D I+ indicates a divider.

In addition, in FIG. 1, a portion from the reed of the wind instrument to the first tone hole and a portion corresponding to the terminal end of the wind instrument are illustrated, and illustration of other portions is omitted. Bidirectional transmission circuit (not shown) B D t
In the section from to the termination circuit TRM, there are bidirectional transmission circuits BDff, . . . depending on the length of the actual wind instrument tube.
, BDn (BDn is the bidirectional transmission circuit closest to the termination circuit TRM) is connected, and a junction J is connected at a position corresponding to the arrangement of tone holes between each bidirectional transmission circuit.
A circuit corresponding to Al and tone hole control circuit 23 is inserted.

FIG. 2 is a block diagram showing the configuration of junction JA. In this figure, parts corresponding to those in FIG. 7 described above are given the same reference numerals. This junction JA is a simulation of a tone hole protruding from the tube as shown in FIG. In such a tone hole structure, when the tone hole is in an open state, a part of the air pressure wave (pressure P3-) flowing out from inside the tube toward the tone hole is reflected at the opening and flows into the tube again ( pressure P3+). Therefore, the air pressure Pj at point j near the tone hole in the tube is pj=a+P++ atPt+ +asPa''...
...-(t o). As described above, P, + is the pressure of the air pressure wave flowing into point j from the lead side, and P, + is the pressure of the air pressure wave flowing into point j from the terminal end side. In this case, the coefficient of each pressure is al-2φ1'/(φ2+φ2+φs') ・-・
...(t +)a2=2φ22/(φ,'+φ,t+φ
3') ...---(12) a3-2φ32/(φ
,'+φ1+φ3...(l 3).

On the other hand, when the tone hole is open, al-2φ1'
/(φ12+φf')...(I4)a, -2φ
, 2/(φ1!+φ!')−・・−・(15)a3−
0...(16).

Also, the pressure P of the pressure wave flowing out from point j to the lead side is -
The pressure P of the pressure wave flowing out to the terminal end side, P3-, and the pressure P3- of the pressure wave flowing out to the tone hole side are respectively as follows: P+-=Pj-P++ (I7) pt-=
pj-pt+ ・・・・・・(18) P3-1 P
j−P3+ (19).

In FIG. 2, the delay circuits DTP and DTR simulate the propagation delay of the air pressure wave in the cylindrical part of the tone hole, so the amount of delay is determined according to the height H of the cylindrical part. There is.

Further, TL is a low-pass filter that simulates acoustic loss due to reflection at the end of the tone hole, and M4 is a multiplier that simulates the reflection of air pressure waves at the tip of the tone hole. A is a subtractor, M
3 is a multiplier, which controls the outflow of air pressure waves from the tube section to the tone hole and the inflow of air pressure waves from the tone hole to the tube section.

The operation of this musical tone synthesis device will be explained below. When the musical tone control information generation circuit 21 generates information indicating the blowing pressure and a note-on signal, a value VA corresponding to the blowing pressure is supplied to the nonlinear element 11 via the subtracter 13, and the output of the nonlinear element I■ is enabled, and its output signal is transmitted to the bidirectional transmission circuits BD, , junction J A + , bidirectional transmission circuit BD7 . ... to the termination circuit TRM. Then, the reflected wave signal from the termination circuit TI (M) follows a path opposite to that described above and is fed back to the nonlinear element !■ via the adder 13. From BDl to termination circuit T
The circuit (up to the RM) enters a resonant state and a musical tone signal is extracted.

In this state, when a tone pole opening/closing signal is sent from the musical tone control information generating circuit 21, the tone hole control circuit 21
3, the control variable X is changed according to this signal. Here, when the tone hole open/close signal changes to "tone pole open", X changes from O to φ3! over time! (φ3 is the diameter of the tone hole). This change corresponds to the change in the effective opening area of the tone hole when the finger pressing the tone hole is released. Further, when the tonehole open/close signal changes to "tonehole closed", X gradually changes from φ3' to 0 as time passes. Then, this control variable
) coefficient calculation is performed.

al(+t)-2φ1! /(φl′+φt”10x)
−・= (20) a, (x) = 2φ, 2/(φ1′+
φ 2 + X ) ... (21) a3 (x) -
2x / (φ12+φt”+ x) −−(22
) and the coefficients a, (x), a2 obtained by the calculation
(x).

a3(x) is applied to multipliers M + , M 2 and M 3, and the level of each signal input to adder Aj is controlled. In this way, signal processing control is performed in response to changes in the scattering state of air pressure waves near the tone hole when the tone hole is gradually opened and closed.

Meanwhile, at the same time, the tone hole control circuit 23
Compute the coefficient r(x) for multiplier M.

Note that illustration of a circuit that performs this calculation is omitted.

Here, the coefficient f is r(o)=t when x=0 (tone hole closed state), and f(φ3") when x=φ3 (tone hole open state) - ISx is O~φ32 In this case, f gradually decreases as X increases.Then, the coefficient f obtained by the calculation is given to the multiplier M4.In this way, the coefficient f obtained by the calculation is given to the multiplier M4. Signal control is performed corresponding to changes in the reflection characteristics of pressure waves at the tip.Then, the coefficients a, (x), a, (x), a3(x
), f(x) changes, the resonance waveform changes in this musical tone synthesizer, and changes in the musical tone signal corresponding to when the tone hole is gradually opened or closed are reproduced. .

Above, we have explained the case where the tone holes are raised from the pipe part as shown in Fig. 3, but as shown in Fig. 6 mentioned above, the hole is simply made in the pipe part (that is, the height H= 0
) tone hole case will be explained. in this case,
The junction shown in FIG. 7 is used, and the coefficient calculator of the tone hole control circuit 23 is shown in FIG. In FIG. 5, M 21 , M 21
is a multiplier, A21 is an adder, and D! l indicates a divider. By inputting the control variable
is executed, and coefficients a1(x), a, and (x) are obtained. Then, the coefficients L(X) and at(x) are a++
is given to the multiplier M = , M t as at. By doing this, similar to the case of the tone hole structure shown in Fig. 3 above, in the tone pole structure shown in Fig. 6, changes in the musical tone when the tone hole is gradually opened and closed are reproduced. be done.

Although the present invention has been described above for synthesizing musical tones simulating a wind instrument, the present invention is not limited to this. It can also be used to simulate changes in the reverberation effect that occur when Furthermore, it can be applied to simulate the vibration of a stringed instrument when the strings of a stringed instrument are lightly touched with something (for example, a finger).

"Effects of the Invention" As explained above, according to the present invention, by providing the third signal processing means that simulates a raised tone hole, wind instruments, sound fields, etc. can be simulated more accurately. The effect is that realistic musical tones can be synthesized.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the structure of a musical tone synthesizer according to an embodiment of the present invention, FIG. 2 is a block diagram showing the structure of a junction JA in the same embodiment, and FIG. 3 is a block diagram showing the structure of a tone hole in the same embodiment. FIG. 4 is a block diagram showing the configuration of the coefficient calculation circuit built into the tone hole control circuit 23 in the same embodiment. FIG. 5 is a diagram showing another example of the coefficient calculation circuit. FIG. 7 is a diagram illustrating the schematic configuration of a wind instrument, and FIG. 7 is a block diagram showing the configuration of a conventional musical tone synthesis device. ! I...Nonlinear element, B D l, B D
* , ~... Bidirectional transmission circuit, J A +...
23... Tone hole control circuit, 2I... Musical tone control information generation circuit.

Claims (4)

[Claims] (1) First to third signal processing means, each of which applies a predetermined delay time to an input signal and outputs the result, and the output signals of the first to third signal processing means are used as input signals, and these a coupling means for performing predetermined arithmetic processing between input signals and sending the result to the first to third signal processing means, and bringing the first to third signal processing means and the coupling means into a resonant state. A musical tone synthesis device characterized in that a musical tone signal is generated by. (2) At least one of the first to third signal processing means
2. The musical tone synthesis apparatus according to claim 1, wherein the input signal is delayed by a predetermined time and subjected to level control before being outputted. (3) first and second signal processing means each delaying an input signal by a predetermined time and outputting the result; and a third signal processing means applying frequency band control to the input signal and outputting the resultant signal. , a coupling means that takes the outputs of the first to third signal processing means as input signals, performs predetermined arithmetic processing on these input signals, and sends the results to the first to third signal processing means. A musical tone synthesis device, characterized in that a musical tone signal is generated by bringing the first to third signal processing means and the coupling means into a resonant state. (4) The musical tone synthesis apparatus according to claim 3, wherein the third signal processing means applies frequency band control and level control to the input signal and outputs the same.