JP3201553B2 - Electronic musical instrument - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic musical instrument, and more particularly to an electronic musical instrument having a musical tone waveform generating means based on a harmonic synthesis method, the tone of which can be changed based on information such as touch. is there.

[0002]

2. Description of the Related Art Conventionally, some electronic musical instruments have a musical tone generating means of a waveform reading system. This method is
It has a waveform memory storing tone waveforms corresponding to a plurality of timbres, and reads out waveform data from the waveform memory at address intervals corresponding to pitches. In this waveform reading method, the timbre of a musical tone is basically determined by the type of waveform stored in the waveform memory. Therefore,
A very large amount of waveform memory is required to finely change the timbre.

On the other hand, there is a harmonic synthesis system as a second system. This is based on the theory of Fourier synthesis that any periodic signal can be represented by a combination of harmonics that are an integral multiple of the fundamental period, and adds multiple harmonics with different levels (envelopes) depending on the timbre to form an arbitrary musical sound waveform. What you get. Although this method does not require a large amount of memory, it is necessary to obtain the amplitude values of a plurality of harmonics and add them to obtain the value of one sample point of one musical tone waveform.

In an electronic musical instrument of the harmonic synthesis type,
As a technique for changing the tone by touch, for example, as described in Japanese Patent Publication No. 59-17435, control data corresponding to each harmonic is read from a table in accordance with the touch, and the control data corresponding to each tone is read. There has been a method of controlling the harmonic coefficient corresponding to each harmonic generated.

[0005]

In the timbre control method for an electronic musical instrument according to the above-described conventional harmonic synthesis method, control data for controlling a harmonic coefficient is set using touch information and a harmonic order as addresses. Although there is a memory for reading, there is a problem that a very large capacity memory is required to improve the touch resolution.

In addition, since the control data is generated, since information relating to the timbre is not included as an element (no timbre information is included as an address), for example, the degree of change due to the touch between the flute and the violin becomes the same. However, there is also a problem that the degree of change unique to the tone cannot be achieved.

SUMMARY OF THE INVENTION An object of the present invention is to improve the above-mentioned problems of the prior art, and to provide an electronic musical instrument having a musical tone waveform generating means of a harmonic synthesis system with a simple structure and a selected tone color and touch. It is an object of the present invention to provide an electronic musical instrument capable of changing a timbre according to performance information.

[0008]

SUMMARY OF THE INVENTION The present invention relates to a harmonic synthesizing electronic musical instrument, a harmonic signal generating means for generating a fundamental wave constituting a musical tone and its harmonic signal, and a harmonic signal corresponding to a desired tone color. A harmonic information generating means for generating a wave coefficient, and a means for forming a musical tone signal by multiplying the harmonic signal of each order by a corresponding harmonic coefficient and accumulating the result. In the musical instrument, the harmonic information generating means includes a basic harmonic coefficient generating means for generating a basic harmonic coefficient corresponding to a selected timbre and a harmonic order, and the basic harmonic coefficient is calculated by calculating the basic harmonic coefficient. correcting the coefficients, and a coefficient control signal generating means for generating a coefficient control signal for generating harmonics coefficients of each order, the coefficient control signal generating means, each selected tone color
And, the coefficient control signal for changing the characteristics data of each harmonic order - a storage means for storing data, performance is a function of the operating signal the control signal and the coefficient control signal for changing the characteristics de - based on the data, select And a calculating means for calculating the coefficient control signal for each of the selected timbre and each harmonic order.

[0009]

According to the present invention, it is possible to obtain a high-resolution harmonic coefficient control signal based on a tone selected by calculation, performance such as touch information, and operation information without using a large amount of memory. With such a simple configuration, it is possible to change the timbre by touch with the optimum degree of change for each selected timbre.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block diagram illustrating a hardware configuration of an electronic musical instrument according to an embodiment. The CPU 1 controls the entire electronic musical instrument, such as scanning, key assignment, and sound control. The ROM 2 stores programs necessary for control, and data such as harmonic coefficient data and envelope data for each timbre.

The RAM 3 stores panel setting information such as timbre, tempo, volume, etc., various control data in the musical instrument, automatic performance data, and the like. At least a part thereof is backed up by a battery, so that the tone color information and the like set from the panel can be retained even when the power is turned off. The keyboard unit 4 includes a keyboard and a circuit that scans a plurality of key switches of the keyboard under the control of the CPU 1.

The panel unit 5 includes a panel provided with operation switches, a volume and a display such as an LCD or an LED, a panel scan circuit for scanning the panel switches under the control of the CPU 1, and a drive circuit for the display. As will be described in detail later, the tone generator 6 creates waveform information of a desired tone color by a harmonic synthesis method, stores this waveform information in a RAM, and executes a digital tone signal having a pitch corresponding to a keyboard by a waveform readout method. Is to occur. It also includes a sound image effect circuit, a reverberation effect circuit, and the like. D
The / A converter 7 adds and synthesizes digital tone signals of all channels, and D / A converts the signals. The analog signal processing section 8 is a circuit that performs a filtering process for removing noise from the analog musical tone signal.

The amplifier 9 amplifies a tone signal for driving one or a plurality of speakers 10. The bus 11 connects each circuit in the musical instrument. It should be noted that the tone generator is configured to output two left and right stereo signals,
Two systems each from the A converter 7 to the speaker 10 may be provided. In addition, a MIDI interface circuit or the like may be provided.

FIG. 2 is a block diagram showing the internal structure of the tone generator 6 shown in FIG. This tone generation circuit adopts a tone generation method that combines a harmonic synthesis method and a waveform readout method, and stores desired waveform data generated at a predetermined period in non-real time by the harmonic generation method in a waveform memory. Then, using this waveform, a tone signal is generated by tone signal generating means of a waveform readout system. The execution control circuit 20 has a built-in system counter that defines the operation of the musical tone generator 6, and generates various control signals such as a clock, an address signal, and an interpolation signal. Also C
It also includes an interface circuit between the PU 1 and each of the tone generator circuits described below, and this circuit has a buffer memory for exchanging data.

Although described in detail later, the harmonic information generation unit 21 generates a level information for each harmonic in the harmonic synthesis system and stores a built-in buffer memory (to be described later) to transfer the level information to the next waveform calculation unit 22. To the higher harmonic memory 34). The waveform calculator 22 reads the level information of each harmonic from the buffer memory, as will be described in detail later,
Amplitude information for each harmonic is obtained, and the amplitude information is accumulated for each musical tone to output waveform information for each musical tone. This waveform calculation is not performed in real time, and a plurality of waveform data in the waveform memory 23 is updated at a cycle of, for example, about 8 milliseconds.

The waveform memory 23 has three areas A, B, and C.
, And each region is divided into a plurality of (for example, 16 channels) regions for tone generation channels. One cycle of musical tone waveform data (for example, 256 sample points) is written from the waveform calculator 22 to the area of each channel.

A waveform calculator 22 is provided in each channel region of the A region.
When the waveform data has been written from the area B, the previously written waveform data is read from the areas B and C two times before. The reason why the waveforms are read from the two regions is to perform an interpolation operation by the waveform interpolation circuit 26 at the subsequent stage in order to prevent a sudden change in the amplitude value when switching the waveform. When the waveform writing in the area A is completed, the area for writing and reading is switched, and then the waveform data is written to the area B and read from the areas C and A. Control signals for writing and the like are supplied from the execution control circuit 20.

The waveform readout circuit 24 has the same configuration as that of a circuit of a normal waveform readout type, and stores waveform data from a waveform memory at an address interval corresponding to a pressed key and corresponding to a desired tone frequency. Generates an address signal for reading. The selector 25 is connected to the write address from the execution control circuit 20 and the waveform read circuit 24
The read address is switched by the control signal from the execution control circuit 20 and an address signal is supplied to the waveform memory 23.

As described above, the waveform interpolation circuit 26 simultaneously reads the waveform data from two areas other than the currently written area of the waveform memory 23 so that the waveform value does not change abruptly when switching the waveform data. , Perform an interpolation operation and output waveform data. Envelope generator 2
Reference numeral 7 generates tone waveform envelope information based on data set by the CPU 1 in accordance with timbre, touch, and the like. The multiplier 28 multiplies the waveform information output from the waveform interpolation circuit 26 by the envelope information output from the envelope generator 27, and outputs a digital tone signal.

The tone generator 6 has a waveform memory 23, a waveform readout circuit 24, an envelope generator 27, and a multiplier 28, and has the same function as a normal tone readout type tone signal generator. Part of the
By using a ROM or the like that stores waveform data, it is possible to generate a tone signal of the harmonic synthesis method for each channel,
It is also possible to select the tone signal generation of the CM waveform reading method.

Each circuit in FIG. 2 is configured to generate independent tone signals of a plurality of channels by time division multiplexing operation. In the following embodiment, the number of channels will be described as 16. Although not shown, between the multiplier 28 and the D / A converter 7, a sound image effect circuit or a reverberation effect circuit for distributing the tone signal to the left and right and controlling the respective levels may be inserted. .

<Harmonic Information Generator> FIG. 3 is a block diagram showing the internal configuration of the harmonic information generator 21 of FIG.
The harmonic coefficient generator 31 is a memory that stores, for example, basic harmonic coefficient information h for determining a harmonic level for each tone and each harmonic order, and a harmonic order signal output from the execution control circuit 20. In accordance with q (for example, from the first order, that is, from the fundamental wave to the sixteenth harmonic), harmonic coefficient information h for each harmonic order corresponding to the timbre is output. The coefficient control signal generator 32 generates a harmonic coefficient control signal G for correcting the harmonic coefficient h corresponding to, for example, a timbre and a touch, which will be described in detail later. The multiplier 33 multiplies the harmonic coefficient h by the harmonic coefficient control signal G.

The harmonic memory 34 is composed of two regions A and B, and each region is divided into, for example, regions of the first to sixteenth harmonics for one channel. In the area of each harmonic, a harmonic coefficient H for each harmonic is written.

When the harmonic coefficient data is written in each of the harmonic areas in the area A, the data for one channel previously written is read out from the area B to the waveform calculator 22. When the writing of the area is completed, the area for writing and the area for reading are switched. The selector 35 switches the write address WA and the read address RA from the execution control circuit 20 in accordance with a control signal from the execution control circuit 20, and supplies an address signal to the harmonic memory 34.

<Waveform Calculation Unit> FIG. 4 is a block diagram showing the internal configuration of the waveform calculation unit 22 in FIG. The address generator 40 sequentially generates phase information of each harmonic based on a control signal from the execution control circuit 20. This phase information serves as an address signal for reading the amplitude value of each sample point (phase point) of each order harmonic from the sine waveform memory 41. Then, the amplitude information corresponding to each harmonic is read from the sine waveform memory 41 by the address signal.

The sine waveform memory 41 is a memory for storing amplitude value data of, for example, 256 sampling points of a sine waveform. The sine waveform memory 41 may store data for one cycle. Then, 1/2 or 1/4 cycle data can be stored, and 1 cycle data can be obtained by processing the address and the read data.

The multiplier 42 multiplies the amplitude value data read from the sine waveform memory 41 by the harmonic coefficient H read from the harmonic memory 34. Accordingly, at the output of the multiplier 43, the amplitude data of the first to sixteenth harmonics of the desired tone and the tone corresponding to the touch at a certain sample point is obtained in order. The amplitude accumulator 43 accumulates these harmonics for each musical tone (channel), and obtains a waveform amplitude value at one sample point. This waveform amplitude value is sequentially written to the waveform memory 23.

<Operation Timing> FIG.
5 is a time chart schematically showing operation timings of the harmonic information generation unit 21 and the waveform calculation unit 22 of FIG. In the figure, channel numbers are the numbers of channels that independently generate musical tones, and in this example, there are 1 to 16. W means writing and R means reading. In the calculation period of channel 1, the harmonic information generation unit 21 as shown in FIG. 3 calculates the harmonic coefficient H of each harmonic of the musical tone of channel 1 and writes it to, for example, the A region of the harmonic memory 34.

During the operation period of channel 2, the harmonic information generation unit 21 writes the data of channel 2 in the B area of the harmonic memory, and during this time, the waveform calculation unit 22 reads the data of channel 1 from the area A, The amplitude value of each sample point is obtained and written to the waveform memory 23. As described above, the harmonic memory 34 sequentially uses the two areas to alternately pass data for 16 channels, and the waveform memory 23 switches the area when all the waveform data for 16 channels are collected, and the waveform is changed. Be updated.

FIG. 10B is a time chart schematically showing the operation timing of the waveform calculation section 22. The writing cycle to the waveform memory 23 is divided into the number of channels (16), and the operation period of one channel is divided into 256 sample point operation periods. Note that the word number in the figure is the number (address) of the waveform data stored in the waveform memory. Furthermore, each sample point calculation cycle is
It is divided into 16 amplitude value calculation periods for each harmonic. 1
Assuming that the calculation time of two harmonic amplitude values is, for example, 125 nanoseconds, the calculation time of one sample point is 2 microseconds, and the calculation time of the waveform data of one channel is 51 microseconds.
2 microseconds. Therefore, the cycle of calculating the waveforms of all 16 channels and updating the waveforms is about 8.2 milliseconds.

As shown in FIG. 10 (a), the update of the harmonic memory can be performed by updating the harmonic coefficients for 16 channels during 8.2 milliseconds. There are 512 microseconds, during which the harmonic coefficients from the first to the 16th harmonic of one channel may be calculated. If the harmonic coefficient read from the harmonic coefficient generator 31 is changed in the period of 8.2 milliseconds, a musical tone whose timbre changes with time can be obtained.

<Coefficient Control Signal Generator> FIG. 5 is a block diagram showing the internal configuration of the coefficient control signal generator 32 of FIG. The characteristic data memory 50 stores characteristic data for each harmonic for each tone color. One characteristic data is DPH which is information indicating a gradient of a change of a harmonic coefficient control signal with respect to a change of loud information L (generation method will be described later) which is performance and operation information, and an offset of a harmonic coefficient control signal value. It consists of two values, BIAS, which determines the value. These parameters are sequentially read out using the timbre information T and the harmonic order q as addresses, and the DPH signal is output to the multipliers 51 and 54, and the BIAS signal is output to the multiplier 51 and the adder 53.
Supplied to

The multiplier 54 has a touch signal, an operator signal,
Alternatively, loud information L created from performance and operation information such as a key number is input. The complementer 52 inverts the sign of the output value of the multiplier 51 to obtain (BIAS × DPH)
, The adder 53 adds the output of the complementer 52 and the BIAS value, and obtains-(BIAS × DPH).
Further adds the output of the adder 53 and the output of the multiplier 54 to obtain an output G which is a harmonic coefficient control signal. This calculation is executed in synchronization with the harmonic coefficient generator 31 each time the harmonic order q is given from the execution control circuit 20. This operation is represented by the following expression.

G = DPH × L + BIAS−DPH × BIAS.

FIG. 6 is a graph showing the relationship between the loud information L and the control output G when BIAS and DPH take predetermined values. FIG. 6A is a graph showing characteristics when BIAS = 0, and the relationship between L and G is indicated by a straight line passing through the origin (0, 0) and having a slope equal to the DPH value. FIG. 6B shows a BIAS of 0.8, and FIG.
Is a graph showing characteristics when the BIAS is 1.0. In the case of (b), the coordinates pass through the coordinates (0.8, 0.8), and in the case of (c), the coordinates pass through the coordinates (1, 1). It is shown as a straight line. As is clear from the figure, the characteristic of the above equation is such that when the loud information L takes a BIAS value, DP
No matter what value H takes, the output will be a BIAS value.

FIG. 9 is a conceptual diagram showing an example of characteristic data of a certain tone color. If the characteristic data of a certain timbre is as shown in FIG. 9B, the relationship between L and G for each harmonic is a characteristic indicated by a plurality of straight lines shown in FIG. 9A. For example, for the fifth harmonic, BIAS = 1.0, DPH
The characteristic corresponding to = 0.8 is indicated by a straight line A, and in this example, the level of the higher harmonics has a large change due to the loud information L. As is apparent from this figure, by appropriately selecting the BIAS and DPH for each harmonic, for example, for each harmonic of each timbre, L, which is touch information, and a control signal for controlling the level of the harmonic. The relationship of G can be set arbitrarily, and an optimal change can be obtained for each tone color.

As described above, the characteristic data memory 50 stores
Different characteristic data is stored for each timbre.
By appropriately selecting the S value and the DPH value, it is possible to arbitrarily set a manner of changing the harmonic coefficient control signal with respect to the loud information. Therefore, the degree of change of the timbre with respect to the strength of the touch can be optimized for each timbre. Also, the number of characteristic data may be the number of timbres × the number of harmonics × 2, and a small-capacity memory is sufficient.

FIG. 7 shows loud information L which is a performance and operation signal.
FIG. 3 is a functional block diagram showing an example of a signal processing function for obtaining the function, and this function can be implemented by software or hardware. In this embodiment, the loud information L is created from a touch signal, an operator (volume) signal, and a key number. The degree converters 60, 61, and 62 calculate each input signal with a corresponding depth signal by a method described later, and output a signal of 0 or more and 1 or less. Each depth signal may be determined for each tone color, or may be settable from a panel.

The multipliers 64 and 65 multiply the outputs of the three degree converters to output loud information L. The touch signal and the operator (volume) signal are converted into values between 0 and 1, respectively, and each key number value is converted by the conversion memory 63 into a desired key scaling signal having a value between 0 and 1. Is converted to

Here, as the contents of the conversion memory 63, for example, a value close to 1 is read out when the key number is small (the pitch is low), and a value closer to 0 is read out as the key number increases. When the characteristic data as shown in FIG. 9 is used, the higher the pitch, the smaller the higher-order harmonic components, and a softer tone can be obtained. Thus, it is possible to change the timbre according to the pitch. The conversion memory 63 may store a plurality of conversion patterns and select one of the conversion patterns according to the selection signal.

FIG. 8 is a functional block diagram showing the configuration of the degree converter of FIG. The multiplier 70 multiplies the input signal IN by a depth value D which is a control signal, and outputs the result to the adder 73. Further, the sign of the depth value D is inverted by the complementer 71, (−D) is output, and 1 is added by the adder 72. In the adder 73, the output of the multiplier 70 and the output of the adder 72 are added to obtain an output OUT. This circuit performs the following operation when the input signal is IN, the output is OUT, and the depth signal is D.

OUT = D × IN + 1-D.

This circuit is a circuit (or function) when BIAS is set to 1 in the control signal generation circuit of FIG.
Therefore, the characteristics are the same as those shown in FIG. This degree converter controls how much each input signal such as a touch signal and an operation signal is reflected in a change in timbre by a depth signal corresponding to each input. If the depth signal is set to 0, an output is made. The signal is always 1, and the change in the input signal is not reflected at all in the timbre.

As the operator signal, for example, an expression volume signal mainly used for controlling the volume or a signal from a modulation wheel for adjusting the degree of effect control can be adopted. Alternatively, the timbre may be changed by employing a brilliance volume signal. The calculation of the loud information is performed when there is a change in any of the input signals, for example, when a key is turned on or when a change due to an operation of an operation element is detected.

While the embodiment has been described above, the following modifications are also conceivable. In the embodiment, BIAS and DP
The arithmetic expression using H is G = DPH × L + BIAS−D
Although an example in which PH × BIAS is used has been shown, an equation in which (BIAS−DPH × BIAS), which is a constant term of this equation, is used as a BIAS value is also conceivable. That is, G = DPH × L−BIAS ′, and the calculation is simplified. Further, it may include a higher-order term of L2 or more (or -1 or less),
Then, it is possible to realize such a characteristic that the graph showing the characteristic becomes a curve.

In the embodiment, the example of the touch signal and the operation signal has been described. However, if an input that changes with time, such as an envelope generator or an LFO, is used,
The timbre can be changed over time. Further, in the embodiment, the example in which the control based on the touch signal, the control signal, and the key number is performed at the same time has been described, but it is apparent that any one or only two may be performed.

In this embodiment, an example in which waveform synthesis is performed in non-real time has been described. However, the present invention can be applied to an electronic musical instrument of a real-time high-frequency synthesis method as in a conventional example.

[0048]

As described above, according to the present invention, in a harmonic synthesis type electronic musical instrument, a selected timbre,
A high-resolution harmonic coefficient control signal can be obtained based on performance and operation information such as touch information, and the tone can be changed by touch, etc. with a simple configuration and with the optimum degree of change for each selected tone. Becomes possible.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a hardware configuration of an electronic musical instrument.

FIG. 2 is a block diagram showing an internal configuration of a musical sound generation circuit 6;

FIG. 3 is a block diagram showing an internal configuration of a harmonic information generation unit 21.

FIG. 4 is a block diagram showing an internal configuration of a waveform calculator 22.

FIG. 5 is a block diagram showing an internal configuration of a coefficient control signal generator 32.

FIG. 6 is a characteristic diagram showing a coefficient control signal characteristic based on characteristic data.

FIG. 7 is a functional block diagram illustrating a loud information creation function.

FIG. 8 is a functional block diagram showing functions of a degree converter.

FIG. 9 is a characteristic diagram showing an example of characteristic data and characteristics for each harmonic.

FIG. 10 is a time chart showing the operation timing of the musical sound generator.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... CPU, 2 ... ROM, 3 ... RAM, 4 ... keyboard part, 5 ... panel part, 6 ... musical tone generation part, 7 ... D / A converter, 8 ... analog signal processing part, 9 ... amplifier, 10 ... speaker , 11 bus, 20 execution control circuit, 21 harmonic information generation unit, 22 waveform calculation unit, 23 waveform memory, 2
4: Waveform readout circuit, 25: Selector, 26: Waveform interpolation circuit, 27: Envelope generator, 28: Multiplier

──────────────────────────────────────────────────続 き Continuation of front page (58) Field surveyed (Int.Cl. ⁷ , DB name) G10H 1/00-1/053

Claims (4)

(57) [Claims] 1. A harmonic signal generating means for generating a fundamental wave constituting a musical tone and its harmonic signal, a harmonic information generating means for generating a harmonic coefficient corresponding to a desired timbre, and harmonics of each order Means for forming a tone signal by multiplying the signal by a corresponding harmonic coefficient and accumulating the signal to form a musical tone signal. A fundamental harmonic coefficient generating means for generating a fundamental harmonic coefficient corresponding to a wave order, and a coefficient for calculating the fundamental harmonic coefficient by calculating the fundamental harmonic coefficient to generate a harmonic coefficient of each order. Coefficient control signal generating means for generating a control signal, the coefficient control signal generating means comprising: a memory means for storing coefficient control signal changing characteristic data for each harmonic order; and a function of performance and operation signals. In Control signal and the coefficient control signal for changing the characteristics de - based on data, the coefficient control signal for changing the characteristic data and a calculation means for calculating the coefficient control signal for each harmonic order is
At least performance, preset for each harmonic order
Slope of change of harmonic coefficient control signal with respect to change of operation signal
And the offset amount of the harmonic coefficient control signal value
An electronic musical instrument comprising information of a specific value for determining 2. Storage of characteristic data for changing the coefficient control signal.
And at least one of the operations of the coefficient control signal is selected.
2. The electronic musical instrument according to claim 1, wherein the electronic musical instrument is performed for each selected timbre . 3. An electronic musical instrument according to claim 1 or 2, wherein the performance operation signal including at least a touch information. 4. The control circuit according to claim 1, wherein the harmonic coefficient control signal is:
The electronic musical instrument according to any one of claims 1 to 3, wherein the electronic musical instrument is obtained by an arithmetic expression of slope + specific value-(slope x specific value)}.