JPH04204599A - Musical sound signal generating device - Google Patents

Abstract

PURPOSE:To synthetically realize the reverberation effect, resonance effect, and the damper pedal effect of an electronic piano and prevent the deterioration of the tone due to these effects by providing multiple musical sound wave-form output means outputting the preset musical sound wave-forms corresponding to the delay time of a loop circuit, a musical sound wave-form synthesizing means, and an output feedback means. CONSTITUTION:A controller 6 detects the depression of keys of a finger board 2 and actions of a damper pedal 4 and outputs key-on signals KON1-88 and the damper action quantity DMPR. It also generates the delay time DLY1-88 and the string characteristic filter coefficients STRG1-88 and outputs them to a sound source section 8. An information conversion section 18 outputs the damper characteristic filter coefficients DMPF, DMPG and the feedback level FBLEL applied to sound sources 8-1-88. The sound source 8 outputs the musical sound wave-forms with the preset pitch in response to these parameters, they are synthesized by an adder 10 and inputted to a multiplier 12 and an echo plate resonance application section 14. The application section 14 outputs the output signal applied with the resonance effect by an echo plate, an adder 16 adds these inputs and feeds back them to the sound sources 8-1-88.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a musical tone signal generating device, and relates to a musical tone signal generating device, for example, when an electronic piano or the like is constructed using a physical model sound source, the resonance effect and the timbre when a damper pedal is operated. This invention relates to a musical tone signal generating device that achieves changing effects.

[Prior Art] Conventionally, there is a sound source circuit technology that simulates a natural musical instrument such as a piano using a physical model sound source. For example,
In Japanese Patent No. 48109, a musical sound waveform is applied to the input terminal of a filter having desired frequency characteristics, and the musical sound waveform appearing at the output terminal of this filter is delayed and applied again to the input terminal of the filter, so that the musical sound waveform is generated. An electronic musical instrument has been disclosed that circulates through a filter and extracts a musical sound waveform that sequentially changes depending on the characteristics of the filter each time it passes through the filter. According to this, it is possible to well simulate musical tones that are close to the musical tones of natural musical instruments that utilize the vibrations of pipes, strings, or membranes.

On the other hand, in order to achieve the reverberation effect that occurs when a damper pedal is depressed on a piano or the like, conventional electronic musical instruments use a damper pedal to extend the release rate. Furthermore, Japanese Patent Application Laid-Open No. 63-267999 discloses that a musical sound signal is generated from a sound source to simulate resonant strings and obtain a reverberation effect by inputting a musical sound signal from a sound source to a plurality of comb filters corresponding to pitches. An apparatus is disclosed.

[Problem to be solved by the invention] In a sound source circuit that simulates a natural musical instrument using a physical model sound source, such as the one disclosed in Japanese Patent Publication No. 58-48109, it is necessary to comprehensively address reverberation effects, resonance effects, the effects of the damper pedal of an electronic piano, etc. There is nothing to control it.

Furthermore, if the reverberation effect is achieved by simply increasing the release rate using a damper pedal, it is not possible to obtain an effect closer to that of a natural musical instrument.

In a device such as Japanese Patent Application Laid-Open No. 63-267999, which achieves the effect of a damper pedal by simulating resonant strings, it is possible to obtain a reverberation effect close to that of a natural musical instrument. However, in an actual piano, a key-on string that is sounding does not function as a resonant string, but in the above method, the string is also simulated as a resonant string.

For example, if the signal of a key press sound generated in response to a key-on from a PCM sound source is input to a comb filter with the same pitch as the key press sound, the signal will fall into the peak of the comb filter and cause deterioration of the tone. was there.

In view of the problems in the conventional example described above, this invention constructs the entire musical instrument using a physical model sound source, comprehensively realizes reverberation effects, resonance effects, the effects of the damper pedal of an electronic piano, etc. To provide a musical tone signal generating device that does not cause deterioration of timbre even when the effect of the above is activated.

[Means for Solving the Problems] In order to achieve this object, the present invention provides a loop circuit in which an adding means and at least one of a delay means and a filter means are connected in series, and a loop circuit in which a predetermined driving waveform is applied to the adding means. A plurality of musical sound waveform output means are provided with drive waveform generation means for outputting a predetermined musical sound waveform corresponding to the delay time of the loop circuit, and musical sound waveforms output from the plurality of musical sound waveform output means are synthesized to generate a musical sound. It is characterized by comprising a tone waveform synthesis means for outputting as a signal, and an output feedback means for feeding back the output of the tone waveform synthesis means to a loop circuit of the tone waveform output means.

It should be noted that the output of the above-mentioned musical waveform output means may be taken out from anywhere within the loop circuit. Alternatively, outputs may be taken out from a plurality of different positions of the loop circuit and combined.

In order to realize the effect of a damper, a variable filter means that approximates the characteristics of the damper is further connected in series in the loop circuit, and the characteristics of this variable filter means are changed according to the amount of operation of an operator such as a damper pedal. It is a good idea to let them do so.

Furthermore, for musical sound waveform output means to which a driving waveform is supplied from the driving waveform generating means (for example, a sound source from which a corresponding key is pressed), the variable filter means connected to the loop circuit of the musical sound waveform output means is forcibly activated. It is preferable to set the damper to an open state and not to perform feedback by the output feedback means.

[Operation] When a drive waveform is input from the drive waveform generating means to the addition means, this waveform circulates through the loop circuit, and a musical tone waveform is output from an appropriate position within the loop circuit.

The pitch of this musical sound waveform is determined by the delay time of the entire loop circuit. There are a plurality of tone waveform output means each having a drive waveform generation means and a loop circuit, and tone waveforms from each tone waveform output means are synthesized and outputted by a tone waveform synthesis means. Furthermore, this output is fed back to the loop circuit of the tone waveform output means. This loop circuit acts as a comb filter that has resonance peaks at multiple frequency positions that are integer multiples of the frequency of each pitch, and the signal components that are integer multiples of the frequency included in the synthesized output are continuously The rest will be output. As described above, resonance (
Reverberation) effect is realized.

The effect of the damper can be achieved by further connecting in series a variable filter means that approximates the characteristics of the damper in the loop circuit of the musical waveform output means, and changing the characteristics of this variable filter means according to the amount of operation of the operator. Ru. For example, the variable filter means is constituted by a low-pass filter, and the cutoff frequency and filter gain of this low-pass filter increase as the amount of depression of the damper pedal increases.

Further, for the musical sound waveform output means to which the driving waveform is supplied from the driving waveform generating means, the variable filter means connected to the loop circuit of the musical sound waveform output means is forced into the open state of the damper (for example, the amount of depression of the damper pedal If the output feedback means does not perform feedback, the musical sound waveform output means can be made not to be involved in resonance.

[Example] Hereinafter, the present invention will be explained in detail using the drawings.

FIG. 1 shows a block configuration of an electronic piano to which a musical tone signal generator according to an embodiment of the present invention is applied.

The electronic piano of this embodiment has an 88-key keyboard 2 and a damper pedal 4 that is a damper operator.

The control unit 6 detects the depression of a duplicate key on the keyboard 4 and the operation of the damper pedal 4, and outputs key-on signals KON1 to KON88 for each duplicate key and damper operation ffi according to the detection results.
Output DMPR. Further, the control unit 6 generates delay times DLY] to DLY88 and string characteristic filter coefficients 5TRGI to 5TRG88, which are parameters for synthesizing a pitch corresponding to a matching key and a musical tone having the characteristics, and outputs them to the sound source unit 8. . Further, the control unit 6 outputs the overall feedback level FB in the sound source unit 8.

Reference numeral 8 indicates a sound source section (music waveform output means). The sound source section 8 has 88 sound sources 8-1 to 8-88 corresponding to duplicate keys.

18 is an information converter. The information conversion section 18 is connected to the control section 6
damper operation amount DMPR and key-on signal KON
1 to KON88, each sound source 8-1 to 8 of the sound source section 8
- Damper characteristic filter coefficient DMPFI given to 88~
DMPF88. It outputs DMPGI to DMPG88 and feedback levels FBLvL1 to FBLVL88.

The sound source 8-n (n=1 to 88) is a key-on signal K ON
n s delay time DLYn, string characteristic filter coefficient 5TR
Gn, damper characteristic filter coefficient DMPFn, DMPG
n, feedback level FBLVLn, and outputs a musical sound waveform of a predetermined pitch according to these parameters. The outputs from the sound sources 8-n are synthesized by an adder (music waveform synthesis means) 10 and output as a musical tone signal (synthesized output).

On the other hand, this output musical tone signal (synthesized output of the adder 10) is
The signal is input to the multiplier 12 and the soundboard resonance imparting section 14 . Multiplier 12 applies an overall feedback level FB to its input signal.
is multiplied and output to the adder 16. The soundboard resonance imparting unit 14 is a filter that simulates the characteristics of the soundboard of a piano, which is a natural musical instrument. The soundboard resonance imparting section 14 outputs, to the adder 16, an output signal to which the effect of resonance by the soundboard has been imparted. The adder 16 adds these inputs and adds each sound source 8
-1 to 8-88.

Next, the configuration of one sound source 8-n will be explained with reference to FIG.

The sound source 3-n (n=1 to 88) has a loop circuit 29 in which an adder 26, a delay circuit 20, a string characteristic filter 22, and a damper characteristic filter 24 are connected in series. The sound source 8-n also includes an initial drive waveform generator 28 that outputs an initial drive waveform corresponding to the key-on signal KONn. The initial drive waveform output from the initial drive waveform generator 28 is
The signal is supplied to the two loop circuits mentioned above via the adder 26.

The two loop delay circuits 20 delay the input musical tone waveform by a delay time DLYn and output the delayed sound waveform. This sound source 8
The pitch of the musical tone signal generated at -n is determined by the delay time of the entire loop circuit, so here the delay time DLYn
controlled by Note that high-order FIR is used as a filter.
When using a filter with enough delay to obtain the desired pitch, there is no need to prepare a separate delay circuit, and the delay can be controlled by setting the filter coefficients appropriately. What can be done is publicly known.

The string characteristic filter 22 is a filter having a frequency characteristic equivalent to that of a sounding body to be simulated (in this embodiment, piano strings), and changes the input musical sound waveform based on the frequency characteristic and outputs it. The frequency characteristic is the string characteristic filter coefficient 5
It is set for each sound source according to TRGn.

The damper characteristic filter 24 is a variable filter that approximates the characteristics of a damper, and outputs the changed input musical sound waveform based on the damper characteristic. Damper characteristic filter 24
The frequency characteristic of changes depending on the frequency characteristic coefficient DMPFn corresponding to the damper operation m D M PR. The gain characteristic of the damper characteristic filter 24 is a gain characteristic coefficient D M P G corresponding to the damper operation amount DMPR.
It changes depending on n.

The two loop circuit adders 26 are connected to the initial drive waveform generator 2.
The initial drive waveform from 8, the output waveform of the damper characteristic filter 24, and the feedback input from the multiplier 30 are added and output.

The multiplier 30 inputs the feedback of the synthesized output in FIG. 1 as a feedback input FBIN, multiplies this by a feedback level FBLVLn for each sound source, and outputs the result.

The output of the adder 26 becomes the final output as the sound source 3-n.

Next, with reference to FIG. 3, the damper characteristic filter 24 of FIG. 2 will be explained.

The damper characteristic filter 24 used here is basically a low-pass filter. The damper characteristic filter 24 has a loop circuit in which a subtracter 26, a multiplier 28, an adder 30, and a delay circuit 32 are connected in series. Delay circuit 3
The output of 2 is fed back not only to the subtracter 26 but also to the adder 30.

The input waveform INn to the damper characteristic filter 24 is injected into this loop circuit via the subtracter 26 and circulates through this loop circuit.

Multiplier 28 is for controlling the cutoff frequency of this filter 24. The frequency characteristic coefficient DMPFn, which is the multiplier of the multiplier 28, changes depending on the amount of operation (depression amount) of the damper pedal, as shown in FIG. 7, for example. In FIG. 7, the horizontal axis indicates the damper position, and the damper position "0" indicates a state in which the damper pedal is not depressed, and the damper position "1" indicates a state in which the damper pedal is fully depressed. As the amount of depression of the damper pedal increases, the frequency characteristic coefficient DMPFn, which is a multiplier in the multiplier 28, increases, and the cutoff frequency of the damper characteristic filter 24 becomes higher.

The output of damper characteristic filter 24 is taken from the output of adder 30 via multiplier 34 . Multiplier 34 is for level control of this filter 24. Gain characteristic coefficient D M P G n which is the multiplier of the multiplier 34
depends on the amount of operation (depression amount) of the damper pedal.
For example, as shown in FIG. 8, it changes. As shown in this figure, as the amount of depression of the damper pedal increases, the gain characteristic coefficient DMPGn, which is the multiplier of the multiplier 34, increases, and the gain of the damper characteristic filter 24 increases.

Note that the damper characteristic filter may be simply configured with only a multiplier. FIG. 4 shows the damper characteristic filter 24'
An example will be shown in which the multiplier 36 is configured with only the multiplier 36 using the gain characteristic coefficient DMPGn as a multiplier. However, in order to produce the effect of pressing the strings with felt like an actual piano damper pedal, the configuration shown in Figure 3 is preferable.

Next, with reference to FIG. 5, the information converter 18 shown in FIG. 1 will be explained.

The information converter 18 is a circuit that calculates coefficients that define damper characteristics to be applied to the damper characteristic filter 24. The information converter 18 has 88 individual converters 40-1 to 40-88 corresponding to 6 keys. Since each converter has a similar configuration, the converter 40-1 will be explained below.

The converter 40-1 includes N OR circuits, a filter coefficient table 44, a gain coefficient table 46, and a feedback input coefficient table 48.

The OR circuit 42-1 inputs the key-on signal KONI (1 bit) and the first bit of the damper operation ffiDMPR (predetermined number of bits), and outputs the result of the OR operation.

Similarly, the OR circuit 42-n (n=1 to N) inputs the key-on signal KON1 and the n-th bit of the damper operation amount DMPR, and outputs the result of the OR operation. Therefore, the N OR circuits 42-1 to 42-N output the damper operation amount DMPR when the corresponding key is not turned on, and output all bits "1" when the corresponding key is turned on. do.

The filter coefficient table 44 is based on the damper operation amount DMPR.
This is a table storing a list of frequency characteristic coefficients DMPFI corresponding to . Further, the gain coefficient 46 is a table that stores a list of Cain characteristic coefficients DMPG1 corresponding to the damper operation iDMPR.

The filter coefficient table 44 and the gain coefficient triple 46 are read out according to the outputs of the OR circuits 42-1 to 42-N, and the frequency characteristic coefficient DMP F1 and the gain characteristic coefficient DMPGI are output.

If the corresponding key is turned on, table 44
．． Data of all bits "1" is input to 46. This corresponds to forcibly setting the damper operation amount DMPR to "1" (that is, the maximum depression state).

On the other hand, the 1-bit key-on signal KONI and the predetermined bit damper operation ffi D M PR are input to the feedback input coefficient table 48. The feedback input coefficient table 48 shows the damper operation amount D for when the corresponding key is turned on and when the corresponding key is not turned on.
This is a table storing a list of feedback levels FBLVLI corresponding to MPR.

Then, presence or absence of key-on and damper operation amount DMPR
The feedback level FBLVL1 is read out and output in response to this.

Note that normally the key-on string should not be involved in resonance, so if the key-on signal is ON1 or "1", the feedback level FBLVL1 is set to "0" regardless of the value of the damper operation amount DMPR. It is preferable to set the feedback input coefficient table 48 in such a manner.

Further, the feedback input coefficient table 48 may store only information when the key is not turned on, and the table output may be gated using the key-on signal.

FIG. 6 shows a connection example of such a feedback input coefficient table. In this figure, the feedback input coefficient table 50 inputs the damper operation amount DMPR,
A corresponding feedback level FBLVLn is output. This output is input to an AND circuit 54. On the other hand, the key-on signal KONn is inverted by a NOT circuit 52 and input to an AND circuit 54.

Therefore, when the key-on signal KONn is rOJ, that is, the corresponding key is not turned on, the feedback level FBLVLn is output from the AND circuit 54, and when the key-on signal KON,n is "1", that is, the corresponding key is not turned on. When this is the case, data with all bits "0" is output from the AND circuit 54 as the feedback level FBLVLn.

If all bits of the feedback level FBLVLn are "0", this means that the feedback input FBIN is disconnected in the sound source circuit of FIG. 3, and the sound source circuit does not participate in resonance.

Next, the operation of this electronic piano will be briefly explained.

When the keyboard 2 of this electronic piano is pressed, the control section 6 detects this pressing and outputs the corresponding key-on signal KONn1 delay time DLYn and string characteristic filter coefficient 5TRGn. The control unit 6 also detects the operation amount of the damper pedal 4 and outputs the corresponding damper operation amount D M PR and the overall feedback level FB.

The key-on signal KONn output from the control section 6 is input to the corresponding sound source 8-n.

In the sound source 8 - n, the key-on signal KONn is input to the initial drive waveform generator 28 , which supplies the initial drive waveform to the adder 26 of the loop circuit 29 . The initial drive waveform circulates through two loop circuits, and an output waveform is generated and output.

The output of the loop circuit 29, that is, the output of the sound source 8-n, is combined with the output from other sound sources in the adder 10 and output.

Further, the output of the adder 10 is transmitted to the multiplier 12 and the adder 16.
Further, the soundboard resonance imparting section 14 and the adder 16
is input to the feedback input FBIN of all the sound sources 8-1 to 8-88. For each sound source 8-1 to 8-88,
This feedback input FBIN is multiplied by the feedback level FBLVLn and is injected into the loop circuit 29.

As a result of the above, when a certain key is struck and produced in a musical instrument such as a piano, the vibrations propagate through the frame and soundboard of the piano and vibrate all the other strings, producing a resonant sound. Situations can be simulated.

On the other hand, the damper operation amount DMPR output from the control unit 6
is input to the information converter 18 together with the key-on signal KON]--KON-88. In the information converter 18,
Frequency characteristic coefficient DM corresponding to damper operation amount DMPR
PFn, gain characteristic coefficient DMPGn, and feedback level FBLVLn are read and output. At this time, as these parameters given to the sound source corresponding to the key turned on, a value corresponding to the maximum value of the damper operation amount DMPR is forcibly output, and a feedback level FBLVLn for the resonance effect is forcibly output. Outputs "0". Thereby, the key-on sound source can be prevented from generating resonance sound.

Frequency characteristic coefficient DMPF output from the information converter 18
n, the gain characteristic coefficient DMPGn, and the feedback FBLVLn are input to the corresponding sound source 8-n. Frequency characteristic coefficient DMPFn and gain characteristic coefficient DM
PGn changes the characteristics of the two damper characteristic filters 29 in the loop circuit of the sound source 8-n. As a result, a damper effect is applied, and a musical sound waveform of a resonance component is output. Further, the feedback level of the synthesized output can be controlled by the feedback level FBLVLn, and the resonance sound component can be output.

As explained above, in the above embodiment, since the physical model sound source is configured using a loop circuit, it is possible to generate a musical tone that approximates the musical tone of a natural musical instrument such as a piano. In addition, a synthesized output waveform obtained by combining the outputs from each sound source is supplied again to the loop circuit of each sound source, and resonance and reverberation effects are realized by the physical model sound source. Furthermore, a variable filter that approximates the characteristics of a damper is provided in the loop circuit of each sound source to achieve a damper effect using a damper pedal or the like.

In the above embodiment, a plucked string model inputting an initial waveform was used as an example of the physical model, but the present invention is not limited to this, and various excitation signals may be used. For example, instead of the initial waveform, a model simulating a hammer hitting a string may be used.

Although the attenuation characteristics by the damper were approximated by a variable filter inserted into the string loop, a physical model of the damper may also be used.

Although the number of strings is 88, each string may have a plurality of strings, or a model may be used in which there are fewer than 88 strings and the length of the strings is changed in key assignment.

Delay time DLY and string characteristic filter coefficient 5T given to sound source
Although RG is input from the control unit 6, a fixed value may be set in advance.

In the conversion unit 18 of FIG. 5, the feedback input coefficient table 48 is provided for two cases: when the key is turned on and when the key is not turned on.
As shown in FIG. 6, the key-on signal KONn may be used, and the feedback input coefficient table may include only data when the key is not turned on.

However, depending on whether the key is turned on or not, the feedback input signal FB to the loop circuit of the sound source is
Since it is desirable to variably control the IN level as appropriate,
As in the above embodiment, it is preferable to refer to the feedback input coefficient table using a signal obtained by parallelizing the pedal operation mDMpR and the key-on signal KONn as an address.

Since the high-pitched strings of an actual piano are not equipped with a damper mechanism, the sound source corresponding to the high-pitched strings in that range is fixed in the damper open state, even if the corresponding converter 40-1 is omitted. good.

The output from the loop circuit may be taken from anywhere within the loop circuit. Alternatively, outputs may be taken out from a plurality of different positions of the loop circuit and combined. ``For example, only a filter having a delay amount sufficient to obtain a desired pitch may be used in the loop circuit without providing a delay circuit as in the above embodiment. In this case, the amount of delay may be controlled by appropriately setting the filter coefficients.

[Effects of the Invention] As explained above, according to the present invention, the synthesized output obtained by synthesizing the outputs of the sound sources that simulated the physical model is fed back to each sound source, so that reverberation effects, resonance effects, It is possible to comprehensively realize the effects of the damper and the damper.

Further, since the key-on sound source is not involved in resonance, deterioration of tone color is prevented.

[Brief explanation of the drawing]

FIG. 1 is a block configuration diagram of an electronic piano to which a musical tone signal generation device according to an embodiment of the present invention is applied, FIG. 2 is a block configuration diagram of a sound source of this musical tone signal generation device, and FIG. 3 is a sound source FIG. 4 is a block diagram showing another example of the damper characteristic filter; FIG. 5 is a block diagram of the information converter of the musical tone signal generating device; FIG. A block configuration diagram showing a connection example of a feedback input coefficient table, FIG. 7 is a graph showing the correspondence between the damper position and the frequency characteristic coefficient, and FIG. 8 is a graph showing the correspondence between the damper position and the gain characteristic coefficient. . 2... Keyboard, 4... Damper pedal, 6... Control section, 8... Sound source section, 8-1 to 8-88... Each sound source, 1
0.16... Adder, 12... Multiplier, 14...
Soundboard resonance imparting section, 18... Information conversion section, 20... Delay circuit, 22... String characteristic filter, 24... Damper characteristic filter, 26... Adder, 28... Initial drive Waveform generator, 29... Loop circuit, 30... Multiplier, 42-1 to 42-N... OR circuit, 44... Filter coefficient table, 46... Gain coefficient table, 48... Feedback input coefficient table.

Claims (1)

[Claims] (1) A loop circuit in which an addition means and at least one of a delay means or a filter means are connected in series, and a drive waveform generation means for supplying a predetermined drive waveform to the addition means, and corresponds to the delay time of the loop circuit. a plurality of musical sound waveform output means for outputting predetermined musical sound waveforms; a musical sound waveform synthesizing means for synthesizing the musical sound waveforms output from the plurality of musical sound waveform output means and outputting the synthesized musical sound waveforms as a musical sound signal; and an output of the musical sound waveform synthesizing means. and output feedback means for feeding back the output signal to the loop circuit of the musical sound waveform output means.