JPH0546179A - Musical sound synthesizing device - Google Patents

Abstract

PURPOSE:To simulate vibration which is propagated in a sound board by a waveguide network as to a physical model of a piano, a guitar, etc. CONSTITUTION:The waveguide network consists of plural waveguides which are connected by junctions in a mesh state. Each of the waveguide consists of a delay element and a filter element. The musical sound signal from a sound source is supplied to the junction at a point P1 and propagated in the waveguide network. Each waveguide delays the circulated musical sound signal by the delay element simulating the delay of the vibration of the sound board and shapes the signal by the filter element simulating the frequency characteristics of the sound board. Then the musical sound signal is led out of the junction at a point P2 of the waveguide network and used to generate a musical sound.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a musical tone synthesizing device for simulating a sounding mechanism of a piano, a guitar or the like, and a musical tone synthesizing device in which a resonance body is modeled by a network formed by delays and filters.

[0002]

2. Description of the Related Art Conventionally, there is known a device for synthesizing a musical sound of a natural musical instrument by simulating a sounding mechanism of the natural musical instrument. As a musical tone synthesizer for a stringed instrument sound or the like, a low-pass filter simulating reverberation loss of a string and a delay circuit simulating propagation delay of vibration in the string are connected in a closed loop, or a multi-stage FIR filter is used. A structure that simulates vibration of a string is known. In such a configuration, when an excitation signal such as an impulse is introduced into the closed loop circuit, the excitation signal circulates in the closed loop. in this case,
The excitation signal makes a round in the closed loop at a time equal to the vibration period of the string, and is band-limited when passing through the low-pass filter. Then, the signal circulating in the closed loop is taken out as a musical tone signal of the stringed instrument.

According to such a musical sound synthesizer, by adjusting the characteristics of the excitation signal and the low-pass filter, musical sounds close to natural stringed instrument sounds such as plucked string instrument sounds such as guitar and plucked string instrument sounds such as piano are synthesized. it can. A technique of this kind is disclosed in, for example, Japanese Patent Laid-Open No. 63-40199 or Japanese Patent Publication No. 58-58679.

[0004]

By the way, in the above-described conventional musical tone synthesizer, much attention has not been paid to the simulation of the resonance system of a natural musical instrument. Therefore, the musical sound synthesized by the device does not correspond to the effect of vibration of the soundboard or the like, and the difference in waveform between channels such as stereo output does not correspond to the physical phenomenon. Therefore, there arises a problem that it is not possible to faithfully synthesize a musical sound corresponding to the vibration of the resonance system in an actual natural musical instrument.

The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a musical tone synthesizer capable of synthesizing a musical tone corresponding to the vibration of a resonance system in a natural musical instrument.

[0006]

In order to solve the above problems, according to the invention of claim 1, in a tone synthesizer for simulating a tone generation system of a tone of a natural musical instrument, a resonance body of the natural instrument is used. A plurality of closed loop circuits including delay means simulating a delay time delayed when vibration propagates and filter means simulating characteristics of the resonator, and a plurality of closed loop circuits having a predetermined geometric shape. Connecting means for simulating, forming a mesh network of the plurality of closed loop circuits, synthesizing signals circulating through the connected closed loop circuits, and returning the synthesized signal to each closed loop circuit again; A tone signal is supplied to at least one point in the closed loop circuit and is output from at least one point in the closed loop circuit. And wherein the door.

According to a second aspect of the present invention, in the first aspect of the present invention, the circuit network including the closed loop circuit and the coupling means is three-dimensional so as to simulate vibration propagation in a space around the resonator. It is characterized in that it is configured.

[0008]

According to the first aspect of the present invention, a plurality of closed loop circuits are connected by a plurality of coupling means to form a mesh circuit network. Then, a tone signal is supplied to at least one location of the closed loop circuit. The musical tone signal circulates in a closed loop circuit and a junction that form the above-mentioned circuit network, and is output from at least one portion of the closed loop circuit. The tone signal output from the closed loop circuit is sounded as a predetermined tone.

According to a second aspect of the invention, in the first aspect of the invention, the musical tone signal is supplied to a three-dimensionally configured network consisting of a closed loop circuit and the coupling means. The musical tone signal circulates in a closed loop circuit and a junction that form the above-mentioned circuit network, and is output from at least one portion of the closed loop circuit. The tone signal output from the closed loop circuit is sounded as a predetermined tone. This simulates the vibration propagation of the resonance system and the vibration propagation in the space around the resonance system.

[0010]

Embodiments of the present invention will now be described with reference to the drawings. [Basic Principle] First, the basic principle of the present invention will be described. For example, in a piano or the like, when a player presses a keyboard, a hammer corresponding to the keyboard strikes a string. As a result, the string vibrates, and the vibration of the string propagates to the soundboard of the piano through the bridge. As a result, the music that you can actually hear is
The sound will be the vibration of the soundboard added to the vibration of the strings.

The vibration of the soundboard is propagated according to the physical characteristics of the soundboard. Therefore, in order to simulate the musical sound corresponding to the vibration of the soundboard, the physical characteristics of the soundboard may be realized. In particular, it is necessary to consider the frequency characteristics of the soundboard in order to consider the sound quality of musical sounds. The timbre of a piano can be said to be the state of time change of the frequency characteristic of the sound (spectrum envelope), and in that sense, the frequency characteristic of the soundboard has a great influence on the piano sound.

FIG. 1 shows the soundboard (square) described above in a distributed constant manner. In this figure, a circuit NT1 for simulating a soundboard is composed of a plurality of wave guides connected in a mesh. Each line segment L1, L1, ... Shows a wave guide, and each intersection C,
C indicates a junction for combining the output signals of the waveguide.

As shown in FIG. 2, each wave guide 1 comprises an adder 2, a delay element 3, a filter element 4, a multiplier 5, an adder 6, a filter element 7, a delay element 8 and a multiplier 9. It is a loop circuit. Adder 2
Is subtracted from the output signal OUT1 of one of the junctions 10 and the output signal OUT2 of the delay element 8 circulating in the waveguide 1 and supplied to the delay element 3.

The adder 6 subtracts the output signal OUT4 of the filter element 4 circulating in the waveguide 1 from the output signal OUT3 of the other junction 11 and supplies it to the filter element 7. This simulates that the vibration propagated from one point to another point of the soundboard by the adder 2 is reflected at the other point and returns to the one point, and the vibration propagated from the other point to the one point by the adder 6 is It simulates the reflection at one point and the return to another point. At this time, the multipliers 5 and 9 respectively simulate the transmittance of vibration, and after multiplying the transmittance, the respective junctions 1
Supply to 0 and 11.

Each of the delay elements 3 and 8 simulates the delay of vibration in the soundboard. In the case of this example,
It is composed of a shift register. Each stage of this shift register is composed of flip-flops corresponding to the number of bits of a digital signal to be transmitted. The delay time is set by setting the number of flip-flop stages. The delay element 3 delays a signal corresponding to vibration propagating from the junction 10 at one point to the junction 11 at another point by a predetermined delay time, and then supplies the signal to the filter element 4. In addition, the delay element 8
Delays a signal corresponding to the vibration propagating from the junction 11 at the other point to the junction 10 at the one point by a predetermined delay time. As the delay time described above, naturally, a propagation delay amount corresponding to the distance between the junctions 10 and 11 is given.

Each of the filter elements 4 and 7 simulates a frequency characteristic in damping vibration, and attenuates a predetermined frequency band of the signal. Further, in FIG. 1, for example, as shown in FIG. 3, a junction 12 at an intersection of four line segments as shown by a point P1 is supplied with signals from four wave guides 13, 14, 15 and 16 respectively. After combining them, they are returned to the respective wave guides 13, 14, 15 and 16 again. On the other hand, as shown in FIG. 4, the signals from the three-way wave guides 18, 19 and 20 are supplied to the junction 17 at the intersection of the three line segments as shown by the point P2. It is adapted to be returned to the respective wave guides 18, 19 and 20 again.

A musical tone signal from a sound source (not shown) is input to an arbitrary junction on the mesh, taken out from the arbitrary junction, and sounded as a musical tone by a predetermined sound system. In this example,
The tone signal is input to points P4, P5 and P6 shown in FIG. 1 and output from points P7 and P8. Next, as a modified example of the present invention, the wave guide networks NT2, NT3 and NT4 according to other embodiments are shown in FIGS.
Indicates. In each of FIGS. 5, 6 and 7, each line segment L2, L2, ... Shows a wave guide including a delay element and a filter element, and the intersection C of each line segment.
2, C2, ... Indicates a junction.

In FIG. 5, the intersections (junctions) of the waveguide network shown in FIG.
It is connected by one wave guide and one junction. As a result, a more detailed simulation can be performed. Further, in FIG. 6, the basic shape is to connect three wave guides by one junction so that the mesh shape is a hexagon, and in FIG. 7, the triangular shape is a basic shape.

The size of the mesh of the above-mentioned waveguide network should be made as small as possible in order to express even high frequency vibrations. Next, an example of simulating the vibration of a piano soundboard using the above-mentioned wave guide network, particularly the wave guide network NT2 shown in FIG. 5, will be described. Figure 8
Is a wave guide network NT5 that simulates the vibration of a piano soundboard. In FIG. 8, the wave guide network NT5 is configured in the shape of a soundboard of a piano. When the soundboard is divided by the number of meshes shown in the drawing, each mesh is divided into horizontal line segments L3 as shown in FIG. Is about 20 cm, the vertical line segment L4 is about 25 cm, and each diagonal line segment L5 is about 16 cm. Therefore, the propagation delay amount corresponding to the length of the line segment is set in the delay element of the waveguide of each line segment.

An example of calculating each delay amount will be described. Generally, in an actual piano, the sound velocity of wood that constitutes the soundboard varies depending on its material, grain, etc.
Required experimentally. Here, each line segment L shown in FIG.
The sound speeds of 3, L4, and L5 are C1 [m in the lateral direction, respectively.
/ S], C2 [m / s] in the vertical direction, and C3 in the diagonal direction.
[M / s]. In addition, the sampling frequency FS is set to 4
When the frequency is 8 kHz, the delay stage numbers D1 to D3 corresponding to the respective line segments L3, L4, and L5 are as follows.

D1 = (L3 × FS) / (100 × C1) = (20 × 48 × 10 ³ ) / (100 × C1) = 9600 / C1 [stage] ……………………………… ……………… (1) D2 = (L4 × FS) / (100 × C2) = (25 × 48 × 10 ³ ) / (100 × C2) = 12000 / C2 [stage] …………………… ……………………… (2) D3 = (L5 × FS) / (100 × C3) = (16 × 48 × 10 ³ ) / (100 × C3) = 7680 / C3 [step] ………… ………………………………………… (3)

The number of delay stages D1 to D3 obtained as described above is set to the delay elements of the waveguide corresponding to the line segments L3, L4 and L5, respectively.
Further, in wood, the propagation of vibration in the direction along the grain direction is larger than the propagation of vibration in the direction orthogonal to the grain, so this is simulated by the gain of the filter.

The tone signal from the sound source is supplied to the junction at a location corresponding to each tone range. In this example, the tone signal output by the low-pitched sound source (not shown) is multiplied by the weighting coefficient WC1 shown in FIG.
Is supplied to the junction. A signal output from a sound source (not shown) in the midrange is multiplied by the weighting coefficient WC2 shown in FIG. 10 and then supplied to the junction at the point P11. Further, the tone signal output by the sound source (not shown) in the treble range is weighted by being multiplied by the coefficient WC3 in the same manner as in the above-mentioned bass range and midrange range, and then weighted.
Supplied to 2 junctions.

The wave guide network NT5
A musical sound signal circulating through the sound source is taken out from an arbitrary junction, in this example, points P13, P14 and P15, and is sounded as a musical sound by a predetermined sound system. Next, not only a planar lattice but also a three-dimensional modified example will be described with reference to the model shown in FIG. In FIG. 11, a propagation system in a piece is realized. In this embodiment, a wave guide network NT1 simulating a soundboard is provided with a wave guide NT6 simulating the propagation system of the frame on a mesh. This Waveguide Network NT
Similarly to the network 6 described above, each line segment represents a wave guide and each intersection represents a junction. If the sound source is each string, the tone signal from the sound source (not shown) is supplied to point P16 shown in FIG.

Up to now, mainly the planar vibration propagation has been described, but as the wave guide network NT7 for simulating the three-dimensional vibration propagation, a mesh is formed in a rectangular parallelepiped shape (basic shape) as shown in FIG. Alternatively, as shown in FIG. 13, a wave guide network NT8 may be formed by connecting the junctions provided at the corners forming the cube to the respective junctions by means of waveguides. In these cases, since it is possible to simulate three-dimensional vibration propagation, it is possible to give a reverberation effect by simulating a space near the piano, for example. With grand pianos, etc., it is known that there is a large difference in timbre and volume between when the upper roof is opened and when it is closed.However, the present invention is used to simulate the space between the soundboard and the roof. It is possible to realize those effects.

Further, in FIG. 11, the sound board or bridge, which is originally three-dimensional, is approximated in a plane by considering the portion that contributes to the vibration. It is also possible to express it more accurately using a specific structure. According to the above-described embodiment, the vibration propagation of the soundboard is simulated by the planar waveguide network, and the vibration of the soundboard or bridge or the space around it is simulated by the three-dimensional waveguide network. Propagation can be simulated.

In the above embodiment, any number of musical tone signals may be input to the wave network. Further, in the above-mentioned embodiment, any number of output points of the tone signal from the wave network may be used.

[0028]

As described above, according to the present invention, a plurality of closed loop circuits are connected by a plurality of coupling means to form a mesh circuit network, and a tone signal is provided at at least one location of the closed loop circuit. Is supplied and is output from at least one position of the closed loop circuit, so that there is an advantage that a musical tone corresponding to the vibration of the soundboard in the natural musical instrument can be synthesized.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of a model showing a configuration of an embodiment of the present invention in a distributed constant manner.

FIG. 2 is a block diagram showing a configuration of a wave guide of this embodiment.

3 is a block diagram showing a configuration of a waveguide network at an intersection P1 in FIG.

4 is a block diagram showing a configuration of a waveguide network at an intersection P2 in FIG.

FIG. 5 is a conceptual diagram of a model showing a configuration of a wave guide network in which the mesh shape is changed.

FIG. 6 is a conceptual diagram of a model showing the configuration of a wave guide network in which the mesh shape is changed.

FIG. 7 is a conceptual diagram of a model showing the configuration of a wave guide network in which the mesh shape is changed.

8 is a conceptual diagram of a model showing a wave guide network that simulates vibration of a soundboard of a piano using the model shown in FIG.

9 is an explanatory diagram for explaining a length of one mesh of the wave guide network in FIG. 8 with respect to a soundboard.

FIG. 10 is an explanatory diagram for explaining weighting coefficients of musical tone signals supplied to the wave guide network in FIG.

FIG. 11 is a conceptual diagram of a model showing a waveguide network for simulating a propagation system in a piece.

FIG. 12 is a conceptual diagram of a model showing a modified example of a waveguide network for simulating a propagation system in the frame in FIG.

13 is a conceptual diagram of a model showing a modified example of the waveguide network for simulating the propagation system in the frame in FIG.

[Explanation of symbols]

1 ... Wave guide net, 2, 6 ... Adder, 3,
8 ... delay element, 4, 7 ... filter element, 5, 9
…… Multiplier, 10, 11 …… Junction, NT1,
NT2, NT3, NT4 and NT5 ... Wave guide net.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁵ Identification number Internal reference number FI Technical indication location G10K 15/12 (72) Inventor Higashi Iwao 10-1 Nakazawa-machi, Hamamatsu-shi, Shizuoka Yamaha Stock Company

Claims (2)

[Claims] 1. A musical tone synthesizer for simulating a tone generation system of a natural musical instrument, comprising: delay means for simulating a delay time delayed when vibration propagates through a resonant body of the natural musical instrument; and the resonant body. A plurality of closed-loop circuits consisting of a filter means for simulating the characteristics of, and the plurality of closed-loop circuits are connected so as to simulate a predetermined geometric shape, and the plurality of closed-loop circuits form a mesh circuit network. , A coupling means for synthesizing a signal circulating through the connected closed loop circuits and returning the synthesized signal to each closed loop circuit again, wherein the musical tone signal is supplied to at least one point in the closed loop circuit, and
A musical sound synthesizer which is output from at least one location in the closed loop circuit. 2. The circuit network comprising the closed loop circuit and the coupling means is three-dimensionally configured to simulate vibration propagation in space around the resonator. Musical sound synthesizer.