JP2682245B2 - 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 that generates a plurality of musical tone waveforms, filters and synthesizes them.

[0002]

2. Description of the Related Art Generally, there is known a waveform memory system in which a musical tone waveform to be sounded is stored in a waveform memory as a sound source of an electronic musical instrument and the musical tone waveform is read out as it is to form a musical tone signal. By using this method, it is possible to generate high-quality musical sounds that are extremely similar to natural musical instruments.

The following are examples of conventional electronic musical instruments that employ such a system. First, there is the one described in Japanese Patent Laid-Open No. 59-105694. In this electronic musical instrument, the tone color of the musical tone is controlled according to the keyboard touch information, and further, the volume, the decay time, the pitch fluctuation, etc. are also required. Is also in control. That is, a plurality of waveforms are mixed at a mixing ratio according to the touch of the key.

Secondly, there is one disclosed in Japanese Examined Patent Publication No. 1-26322. In this electronic musical instrument, a tone color change such as a key scaling control is realized by appropriately mixing a memory read waveform and a filter output. ing.

Thirdly, there is the one described in Japanese Patent Publication No. Sho 64-7400. In this electronic musical instrument, the coefficient time is controlled by controlling the digital waveform signal read from the waveform memory using a tone color control digital filter. To change the tone color according to key touch or pitch.

Fourth, there is one disclosed in Japanese Examined Patent Publication No. 62-131297, in which, in this electronic musical instrument, the generated digital musical tone signals are independently filtered by a digital filter (FIR) in a time division of a plurality of sequences. Further, by re-sampling in synchronization with the pitch, pitch synchronization of the musical tone signal is performed without imposing an excessive burden on the calculation speed of the digital filter.

[0007]

However, in such a conventional electronic musical instrument, it is possible to generate a plurality of musical tone waveforms and filter and synthesize them, respectively. As a matter of course, there is a problem that a minute filter is required and the hardware configuration scale becomes large. In particular, if an attempt is made to obtain a complicated tone color change, the configuration scale will be significantly increased.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide an electronic musical instrument that can obtain complicated tone color changes with a relatively simple structure and can reduce the hardware structure scale.

[0009]

In order to solve the above problems, in the present invention, a musical tone waveform generating means for generating a plurality of musical tone waveform signals based on performance information and a filter coefficient for generating a plurality of filter coefficients are provided. said generating means, a waveform synthesis means for the composite to a plurality of musical tone waveform signal at an arbitrary ratio to output a composite waveform signal, said plurality of filter coefficients double
Filter coefficient synthesizing means for synthesizing at a rate matching the synthesizing rate of the number of tone waveform signals and outputting a synthesized filter coefficient,
Filter means for filtering the composite waveform signal based on the composite filter coefficient.

[0010]

In the present invention, a plurality of filter coefficients are used for a plurality of musical tones.
Combining according to the combining ratio that matches the combining ratio of the waveform signal ,
The combined output of a plurality of tone waveform signals is filtered according to the combined filter coefficients. That is, the generated waveforms are appropriately synthesized, and after being made into one musical tone, it is filtered according to the synthesized filter coefficient and output as a musical tone signal. Therefore, unlike the conventional configuration in which filters for the number of sequences to be synthesized are required , the tone color is converted into a signal obtained by synthesizing a plurality of tone waveform signals with one configuration of the filter means.
It is possible to make a change , a complicated tone color change can be obtained with a relatively simple configuration, and the hardware configuration scale can be reduced.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of an embodiment of the present invention, and the present invention is an application example in the case of synthesizing two series of waveforms.

In FIG. 1, a keyboard (performance information generating section) 1
Generates performance information in accordance with the performance of the performer and controls the control unit 2
(Control signal generating means). The setting section 3 sets the first series of tone colors and the second series of tone colors, and outputs control signals of the first series tone color designating signal TC1 and the second series tone color designating signal TC2 to the control section 2. The control unit 2 generates a key-on signal KON, a key-depression touch data TOUCH, and a key code KC based on the performance information from the keyboard 1, and also generates a key-depression touch data TOUC.
Based on H, the first-series waveform synthesis coefficient MX1, the second-series waveform synthesis coefficient MX2 for determining the ratio of the first-series waveform and the second-series waveform in the synthesized waveform output A first-series filter coefficient synthesis coefficient FMX1 and a second-series filter coefficient synthesis coefficient FMX2 for determining the ratio between the first-series filter coefficient and the second-series filter coefficient are generated. Composite ratio of two series, namely MX1 and FMX1, MX2 and FMX2
Are made equal to each other as shown in FIG. Further, based on the control signal from the setting unit 3, the first series tone color parameter data TC1PAR and the second series tone color parameter data TC
Generates 2PAR. The control unit 2 selects one of these various signals.
The key-on signal KON, the touch key data TOUCH, the first series tone color parameter data TC1PAR, the second series tone color parameter data TC2PAR, and the key code KC are output to the waveform reading control unit 4 (reading control means), and the filter coefficient supply control unit is also provided. 5 (reading control means), key-on signal KON,
Key touch touch data TOUCH, first series tone color designation signal TC1, second series tone color designation signal TC2, key code KC are output, and key-on signal KON is output to envelope generator (EG) 6.
The key touch touch data TOUCH and the amplitude EG parameter EGPAR are output, the first sequence filter coefficient synthesis coefficient FMX1 and the second sequence filter coefficient synthesis coefficient FMX2 are output to the multiplier 7, and the first sequence waveform synthesis coefficient is further output to the multiplier 8. MX1 outputs the second sequence waveform synthesis coefficient MX2.

The waveform read control unit 4 controls the waveform memory 10 (tone waveform generating means) according to the time-divisional operation clock φ with respect to the first series waveform address AD1 and the second series waveform address AD2.
Is output. The waveform memory 10 is composed of a first waveform memory 10a and a second waveform memory 10b, and stores waveform data relating to musical tones of the first series and the second series, respectively. Specifically, the waveform data relating to a waveform having a plurality of predetermined cycles out of all waveforms from the start to the end of musical tone generation is digitally stored. First waveform memory 10
a and the second waveform memory 10b are based on the first series waveform address AD1 and the second series waveform address AD2, respectively.
The series waveform data read output WAVE1 and the second series waveform data read output WAVE2 are output to the waveform interpolating unit 11 (tone waveform synthesizer). The waveform interpolating unit 11 includes a first sequence waveform and a second sequence waveform.
It performs a process for synthesizing a series of waveforms, and is composed of the multiplier 8 and the cumulative adder 12 described above. The multiplier 8 has a first series waveform synthesis coefficient MX1 and a second series waveform synthesis coefficient.
The first series waveform data read output WAVE1 and the second series waveform data read output WAVE2 read from the waveform memory 10 based on MX2 are multiplied, and the cumulative adder 12 multiplies the multiplication result of the multiplier 8 by the time division operation clock. φ and channel processing cycle clock φa Accumulate, add and output composite waveform
It is output to the FIR filter 13 (filter means) as WAVE.

On the other hand, the filter coefficient supply controller 5 sends the first series filter coefficient memory address FAD to the coefficient memory 14 (filter coefficient generating means) in accordance with the operation clock φ.
1, outputs the second series filter coefficient memory address FAD2. The coefficient memory 14 includes the first coefficient memory 14a and the second coefficient memory 14a.
The coefficient memory 14b is configured to store coefficient data relating to the musical tones of the first series and the second series, respectively. Specifically, as shown in FIG. 2, the coefficient groups are FC1-0 and FC1- in order.
It is stored in memory as 1, FC1-2, ...... FC1-1, ...... FC1-n. At the end, ENDDATA is included, and up to here are the coefficients for one series. Normally, the coefficients from FC1-0 to FC1-n are read sequentially. First coefficient memory 14a
And the second coefficient memory 14b, based on the first series filter coefficient memory address FAD1 and the second series filter coefficient memory address FAD2, respectively.
The second series filter coefficient FC2 is output to the coefficient interpolating unit 15 (filter coefficient synthesizing means). The coefficient interpolating unit 15 performs a process for synthesizing the first series filter coefficient FC1 and the second series filter coefficient FC2, and is composed of the multiplier 7 and the cumulative adder 16 described above. The multiplier 7 reads the first sequence filter coefficient synthesis coefficient FMX1 and the second sequence filter coefficient synthesis coefficient FMX2 from the coefficient memory 14 based on the first sequence filter coefficient synthesis coefficient FMX1.
The series filter coefficient FC1 and the second series filter coefficient FC2 are multiplied, and the cumulative adder 16 accumulates and adds the multiplication result of the multiplier 7 according to the time-division operation clock φ and the channel processing cycle clock φa, and FIR is obtained as the synthesis filter coefficient FC. Output to the filter 13.

The FIR filter 13 digitally filters the input composite waveform output WAVE according to the composite filter coefficient FC, and has a typical configuration as shown in FIG. 3, for example. That is, the FIR filter 13 is shown in FIG.
As shown in FIG. 5, the delay circuits 21-1 to 21-n, the multipliers 22-0 to 22-n, the adder 23 and the coefficient distributor 24 are included. The input (composite waveform output) WAVE from the waveform interpolator 11 is the delay circuits 21-1 to 21-n.
On the other hand, the coefficient FC sent from the coefficient interpolator 15 is supplied to the multipliers 22-0 to 22- by the coefficient distributor 24.
assigned to n, and the filter operation is performed according to the channel processing cycle clock φa.

Further, the envelope generator 6 starts its operation in response to the key-on signal KON, and generates an envelope signal for time-varying the tone color and amplitude of the tone signal formed in each tone generation channel from its rise to fall. And outputs it to the multiplier 31. The multiplier 31 is F
The output of the IR filter 13 is multiplied by the envelope signal,
Output as a musical tone signal.

Next, the operation will be described with reference to the timing chart of FIG. The time division clock φ and the channel processing cycle clock φa are engraved at the timings shown in FIG. 4, and when the keyboard 1 is pressed by the performer, the first waveform memory 10a and the second waveform memory 10b.
From the first series waveform data read output WAVE1-0 ...
The second series waveform data read outputs WAVE2-0 ... Are sequentially and alternately read according to the operation clock φ and output to the waveform interpolating unit 11. Further, the first series waveform coefficient MX1 and the second series waveform coefficient MX2 are alternately and continuously output from the control section 2 to the waveform interpolation section 11. Then, in the multiplier 8, the first sequence waveform synthesis coefficient MX1, the second sequence waveform synthesis coefficient MX2 and the first sequence waveform synthesis coefficient MX1
The series waveform data read output WAVE1-0 ... and the second series waveform data read output WAVE2-0 ... are respectively multiplied, and the accumulator 12 accumulates in accordance with the time division operation clock φ and the channel processing cycle clock φa, Add and synthesize, and FIR as composite waveform output WAVE-0 ...
It is output to the filter 13.

On the other hand, in response to the player's key depression, the first series filter coefficients FC1-0 ... From the first coefficient memory 14a and the second coefficient memory 14b in accordance with the operation clock φ.
..., the second series filter coefficient FC22-0 ... is the coefficient interpolator 15
Is output to In addition, the control unit 2 causes the first series filter coefficient synthesis coefficient FMX1 and the second series filter coefficient synthesis coefficient FM
X2 is alternately and continuously output to the coefficient interpolating unit 15. After that, in the multiplier 7, the first series filter coefficient synthesis coefficient FM
X1 and second series filter coefficient synthesis coefficient FMX2 and first series filter coefficient FC1-0 ..., Second series filter coefficient FC2-0 ...
In addition to multiplying by and, respectively, in the cumulative adder 16, the multiplication result of the multiplier 7 is accumulated and added in accordance with the time-division operation clock φ and the channel processing cycle clock φa to be synthesized, and the synthesis filter coefficient FC-0 ... Is output to the FIR filter 13.

Next, in the FIR filter 13, the input composite waveform output WAVE-0 ... Is combined filter coefficient FC-0.
Based on the channel processing cycle clock φa. After that, the multiplier 31 multiplies the output of the FIR filter 13 by the envelope signal and outputs it as a musical tone signal.

As described above, in this embodiment, the waveform memory 1
The reading of the tone waveform from 0 and the reading of the filter coefficient from the coefficient memory 14 are executed at the time-division timing divided into two, and the waveform and the filter coefficient are respectively multiplied by the corresponding synthesis coefficient. Then, the multiplication results are respectively accumulated and output to the FIR filter 13 as a synthetic waveform and a synthetic filter coefficient, and digital filter processing is performed to generate a musical tone corresponding to the performance information. In other words, a filter is performed by interpolating a coefficient corresponding to each composite waveform to a composite output of a plurality of waveforms according to a composition ratio. In other words, the generated waveforms are appropriately combined, and after being converted into one musical sound, the musical sound is finally obtained.
Specifically, it generates multiple tone waveforms, synthesizes and mixes them according to touch, time, pitch, etc.
The filter 13 controls the tone color. Therefore, unlike the conventional case where the filters corresponding to the number of sequences to be combined are required, the number of digital filters is 1 in this embodiment.
It is possible to obtain complicated timbre changes with a relatively simple structure, and to reduce the hardware structure scale. For example, in the case of synthesizing N series of musical tone waveforms, N independent filters are required in the prior art, but only one filter is required in this embodiment.

In the present embodiment, the two series synthesis ratios, that is, MX1 and FMX1, and MX2 and FMX2 are equal as shown in FIG. 5A, but these are the same as in FIG. Figure 5
As shown in (c), different independent characteristics may be given. Further, these characteristics may be obtained by referring to a table to be accessed based on touch information,
It may be obtained by a predetermined calculation. Further, in addition to touch, the synthesis ratio may be obtained from information based on time, pitch, operation amount of an operator, or the combination thereof.

In the above embodiment, an example of two-series combination is shown, but the present invention is not limited to the case where the number of sequences is two, and it goes without saying that it can be applied to other plural sequences. Further, in the above embodiment, the FI in which the coefficient interpolation / composition is relatively easy
Although the case where the R filter is used is shown, the IIR filter may be used. Further, in the case where the filter other than the FIR filter cannot be used for the coefficient interpolation / synthesis by the simple calculation as in the present embodiment, in such a case, the calculation suitable for the filter to be used may be appropriately performed. , The coefficient is made into a table, and the composition ratio (FMX1, FMX2 in the above embodiment)
It may be referred to according to.

[0023]

As described above, according to the present invention, the synthesized output of a plurality of waveforms is interpolated and filtered according to the synthesis ratio of the corresponding coefficient for each synthesized waveform. Unlike the case where filters corresponding to the number of sequences to be used are required, only one filter is required, and complex tone color changes can be obtained with a relatively simple configuration. As a result, a complicated tone color change can be obtained with a relatively simple configuration, and the hardware configuration scale can be reduced. Also, multiple
Match the filter coefficient with the synthesis ratio of multiple tone waveform signals.
Since it is composed at a certain ratio, multiple musical sound waveforms
There is a correlation between the synthesis of signals and the synthesis of multiple filter coefficients.
This is done by changing the composition ratio arbitrarily.
With, the characteristics of the tone signal are smoothed according to the composition ratio.
The effect that it can be changed is also obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an overall configuration of an embodiment of the present invention.

FIG. 2 is a diagram showing a coefficient group of a filter coefficient memory of the embodiment.

FIG. 3 is a circuit diagram of an FIR filter of the same embodiment.

FIG. 4 is a timing chart showing the operation of the embodiment.

FIG. 5 is a diagram showing an aspect of a combination ratio of two series in the example.

[Explanation of symbols]

1: Keyboard (performance information generator), 2: Control unit (control signal generator), 3: Setting unit, 4: Waveform read controller (Read controller), 5: Filter coefficient supply controller (Read controller) , 6: Envelope generator (EG), 1
0: waveform memory (tone waveform generating means), 11: waveform interpolating section (waveform synthesizing means), 13: FIR filter (filter means), 14: coefficient memory (filter coefficient generating means),
15: Coefficient interpolation unit (filter coefficient synthesizing means)

Claims (1)

(57) [Claims] 1. A musical tone waveform generating means for generating a plurality of musical tone waveform signals based on performance information, a filter coefficient generating means for generating a plurality of filter coefficients, and the plurality of musical tone waveform signals are combined at an arbitrary ratio. A waveform synthesizing means for outputting a synthesized waveform signal; and a combination of the plurality of filter coefficients of the plurality of tone waveform signals.
An electronic musical instrument comprising: a filter coefficient synthesizing unit for synthesizing and outputting a synthetic filter coefficient at a rate corresponding to a synthesis rate; and a filtering unit for filtering the synthetic waveform signal based on the synthetic filter coefficient. .