JPH0664466B2 - Electronic musical instrument - Google Patents

Description

TECHNICAL FIELD The present invention relates to envelope control in an electronic musical instrument.

Conventional technology All waveforms from the beginning to the end of sounding, or waveforms at the rising edge and some of the waveforms after that (a plurality of periodic waveforms) are stored in the waveform memory, and if the former is stored, all waveforms should be read once. Generates a high-quality tone waveform signal,
When the latter is stored, a high quality musical tone waveform signal has recently been generated by reading out one waveform at the rising edge and then repeatedly reading out some of the waveforms thereafter. In this way, it is possible to generate a high-quality musical tone waveform equivalent to a natural musical instrument sound by reproducing the multiple periodic waveforms collected from the natural musical instrument sound as they are on the electronic musical instrument, but the amplitude envelope is stored in the waveform memory. It had the drawback that it was fixed to the object and could not be controlled. It is conceivable to store multiple cycles of musical tone waveforms with various envelope characteristics in the waveform memory, and selectively read the musical tone waveforms according to the desired envelope characteristics, but this will result in enormous memory capacity. So it was unrealistic.

On the other hand, it is generally performed that a musical tone waveform for one cycle is repeatedly generated from the musical tone waveform generating circuit and the amplitude envelope of the musical tone waveform signal is controlled by an envelope waveform arbitrarily generated by parameter control. In this case, the shape of the envelope waveform is determined by variably setting some kinds of parameters, but the obtained waveform shape has its own limits, and there are subtleties in the playing style such as the key touch as seen in natural instrument sounds. It was impossible to faithfully realize the envelope change due to such a difference.

SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and it is possible to realize an envelope control capable of faithfully realizing an envelope change according to a difference in playing style as in a natural musical instrument with a relatively simple configuration. The purpose is to

SUMMARY OF THE INVENTION The electronic musical instrument of the present invention is a pitch designating means for designating a pitch of a musical tone to be generated and for instructing the generation start and muffling start of the musical tone, and the pitch designated by the pitch designating means. Tone waveform generating means for generating a tone waveform signal corresponding to the above, an envelope signal storing means for storing a plurality of different envelope signals for controlling the envelope of the tone waveform signal, and a tone generated by the tone pitch designating means. Detecting means for detecting the time from the generation start instruction to the mute start instruction, and the envelope stored in the envelope signal storage means according to the time from the music sound generation start instruction to the mute start instruction detected by the detecting means. A signal is selected and read out, and the envelope of the musical tone waveform signal generated from the musical tone waveform generating means based on the envelope signal is selected. And a control means for controlling.

The time from the tone generation start instruction to the mute start instruction is detected by the detection means, and the envelope signal stored in the envelope signal storage means is selected and read according to the detected time, whereby the mute start to mute is performed. The attenuation envelope of the musical sound until the completion is controlled.
Therefore, for example, when a keyboard is used as the pitch specifying means, the envelope waveform after key release is selected from the envelope signals stored in the envelope signal storage means according to the length of the key pressing duration. Become. As a result, the envelope waveform after key release can be variously controlled according to the length of the key pressing duration.

That is, according to the present invention, the attenuation envelope for muffling is variously controlled according to the length of the sound generation duration from the start of sound generation to the start of the sound muffling, and the attenuation envelope for mute is adjusted according to the length of the sound generation duration. Subsequent changes in the attenuation envelope can be realized. Moreover, since it is only necessary to store a plurality of different envelope signals, the configuration can be simplified as compared with the case where all the musical tone waveforms are stored.

Embodiment In FIG. 1, a keyboard 10 is used as a means for designating a pitch of a musical tone to be generated, and a key press and a key release on the keyboard 10 are detected by a key coder 11, and a key code indicating a pressed key is shown.
The key coder 11 outputs a key-on signal KON indicating whether or not the key corresponding to KC and the key code KC is continuously pressed. The frequency number memory 12 stores a frequency number (a constant proportional to the frequency) corresponding to each pitch that can be specified on the keyboard 10, and the tone of the pressed key according to the key code KC given from the key coder 11. Read the frequency number F corresponding to high. This frequency number F corresponds to the amount of phase change per unit time, and the phase accumulator
By accumulating this frequency number F at 13 at regular time intervals set by the clock pulse φ,
The instantaneous phase angle information qF that changes at the rate corresponding to the specified pitch is obtained.

In this embodiment, the tone waveform generating circuit is a waveform memory.
It is composed of 14. The waveform memory 14 stores in advance the sample amplitude data of all the waveforms from the start to the end of the musical tone generation, and the sample amplitude data is sequentially read according to the instantaneous phase angle information qF given from the phase accumulator 13. In this case, the phase accumulator 13 does not repeatedly generate the phase angle information for one cycle (2π), but generates the phase angle information indicating the phase angle of all waveforms from the start to the end of the sound generation with absolute addresses. It is assumed that all waveform data in the waveform memory 14 are read once. The phase accumulator 13 is reset to an initial value at the start of sound generation by a key-on pulse KONP generated at the start of pressing a key. All the waveform data to be stored in the waveform memory 14 are sampled from an actual natural musical instrument sound (for example, a piano sound), and are, for example, waveform data with an envelope corresponding to a playing touch of moderate intensity.

The envelope memories 15, 16 and 17 collect actual envelope characteristics corresponding to various rendition styles of a natural musical instrument from the natural musical instrument sound and store them in advance.
The difference in the strength of the playing touch of the natural musical instrument appears remarkably as the difference in the rising characteristic of the amplitude envelope as shown in FIG. 2, for example. Therefore, attack envelope memory 15
Stores the envelope characteristics of natural musical instrument sounds (for example, piano sounds) played with various touch intensities (all waveforms of amplitude envelope corresponding to each touch intensity as shown in FIG. 2). However, in this embodiment, the waveform memory
Since the musical tone waveform data stored in 14 has an envelope corresponding to a medium touch intensity, the attack envelope memory 15 does not have the level data itself at each sample point of the envelope waveform as shown in FIG.
It is assumed that difference data for each sample point between the envelope level of the tone waveform data stored in the waveform memory 14 and the level data of the desired envelope waveform as shown in FIG. 2 is stored. The key coder 11 includes a touch detection means 18, which detects a touch applied to a pressed key on the keyboard 10 and outputs touch detection data. The attack envelope memory 15 selects an envelope waveform corresponding to the touch intensity according to the touch detection data, and converts each sample point data (difference data) of the selected envelope waveform into a phase accumulator.
The phase angle information qF given from 13 is read out sequentially.

In natural musical instruments, when the pronunciation of one pitch is switched to another pitch, the envelope characteristic of the rising part of the tone differs from the normal rising characteristic, and there is a relationship between the two pitches. This shows the unique characteristics. Therefore, in the envelope transient waveform memory 16, the individual transient envelope characteristics (which will be referred to as envelope transient waveform) corresponding to the combinations of the respective pitches (or the pitch range consisting of several pitches) are respectively set in advance. I remember. An example of this envelope transient waveform is shown in FIG. 3 (a).
If the envelope control is not performed by this transient waveform, the sound of the second pitch rises with the normal rising characteristic as shown in FIG. 3B, for example.
When this transient waveform is added to the normal envelope waveform to control the envelope, the envelope of the second pitch is changed as shown in FIG. 3 (c), for example. Although not shown in the figure, the first period is controlled during the period controlled by the envelope transient waveform.
The pitch of the generated sound may be slid toward the second pitch from the pitch.

The circuit 19 for controlling the readout of the envelope transient waveform memory 16 will be described with reference to a key coder.
The key-on signal KON output from 11 is the one-shot circuit 2
In addition to 0, the key-on pulse KONP is output when the value changes from "0" to "1" (when a new key is pressed). The counter 21 is for reading the memory 16 according to the passage of time, is reset at the start of sound generation by the key-on pulse KONP, and immediately after that, performs the counting operation according to the clock pulse φ. The count contents of the counter 21 are input to the memory 16 and all the bits thereof are input to the NAND circuit 22. When the count content reaches the maximum value (all bits “1”), the NAND circuit 22 outputs “0”,
The counting operation of the counter 21 is stopped.

In the envelope transient waveform memory 16, one envelope transient as shown in FIG. 3 (a) is displayed in accordance with the combination of the key code KC of the currently pressed key and the key code OKC of the key pressed immediately before. A waveform is selected, and the selected transient waveform is temporally read according to the output of the counter 21. The current key code KC is given from the key coder 11, and the key code OKC of the immediately preceding pressed key is given from the latch circuit 23. The key code KC given from the key coder 11 is delayed by the delay circuit 24, and the delayed key code is taken into the latch circuit 23 by the key-on pulse KONP. When the key code KC of a new pressed key is output from the key coder 11 at the same time as the key-on pulse KONP, the delay circuit 24 outputs the key code of the immediately preceding pressed key, which is latched by the latch circuit 23. Therefore, while the key code KC of the latest pressed key is output from the key coder 11, the latch circuit 23 outputs the key code OKC of the old pressed key immediately before that. A key code register 25 is provided inside the key coder 11 in order to enable the decay sound after the key is released.The key code KC of the pressed key is maintained even after the key is released until the decay sound is finished. This key code register 25
It is held by and output. The contents of the key code register 25 are cleared by the decay end signal DF.

In this embodiment, when a new key is pressed before the decay of the previous sound is finished, the envelope control by the envelope transient waveform is performed. Therefore, circuits 26-29 control the enabling of memory 16. The first flip-flop 26 is set by the key-on pulse KONP, and the second flip-flop 26
27 is set by the output of the AND circuit 29 which obtains the AND logic of the signal obtained by slightly delaying the set output Q of the first flip-flop 26 by the delay circuit 28 and the key-on pulse KONP. Then, both flip-flops 26, 27 are reset by a decay end signal DF generated as described later at the end of the decay, and the set output Q of the second flip-flop 27 is input to the enable input of the memory 16. Given. Therefore, when the key is newly pressed before the decay of the previous tone is finished and the key-on pulse KONP is generated, the first flip-flop 26 set at the time of the key depression of the previous tone remains set without being reset. For,
Since the set output signal “1” is given to the AND circuit 29 via the delay circuit 28, the condition of the AND circuit 29 is satisfied, and the second flip-flop 27 is set. This second flip-flop 27 enables the memory 16 by the set output "1", and the new key code KC and the old key code OK
The envelope transient waveform corresponding to the combination of C is read according to the output of the counter 21.
On the other hand, when a new key is pressed after the decay of the previous note is finished, the flip-flops 26, 27 are reset by the decay end signal DF, so the key-on pulse KONP
When AND occurs, the condition of the AND circuit 29 is not satisfied, and the second flip-flop 27 is not set.

The dump envelope memory 17 stores dump envelope waveforms of pianos having different characteristics corresponding to various key release timings. The key-on signal KON is inverted by the inverter 30, and the inverted output is the one-shot circuit 31.
The key-off pulse KOFP can be obtained when the key-on signal KON is switched from "1" to "0" (when the key is released). In the latch circuit 32, the phase accumulator
The phase angle information qF output from 13 is latched by the key-off pulse KOFP, and the latched data is input to the memory 17. Since the instantaneous phase angle information qF in the accumulator 13 changes momentarily from the start of sound generation, the key-off pulse KO
If this is latched by the FP, the data corresponding to the key release timing can be obtained. In the dump envelope memory 17, one dump envelope waveform is selected according to the data corresponding to the key release timing latched by the latch circuit 32, and the selected dump envelope waveform is read according to the change in the count value of the counter 33. The counter 33 is reset by the key-off pulse KOFP, and immediately after that, counts the clock pulse φ. Counter 33
When the count value of reaches the predetermined end value, the decay end signal DF is output and the counting operation is stopped.

The envelope waveform data read from the attack envelope memory 15 and the transient waveform data read from the envelope transient waveform are added by the adder 34.
Are added together and the added output is given to the multiplier 35. The dump envelope waveform data read from the dump envelope memory 17 is input to the other input of the multiplier 35.
Given through 36. This dump envelope waveform data is expressed by a coefficient having a minimum value of "0" and a maximum value of "1", and changes rapidly from the maximum value "1" to the minimum value "0". The change characteristic differs depending on the key release timing as described above. The selector 36 selects the output of the dump envelope memory 17 when the key-on signal KON is “0” (that is, during key release) and gives it to the multiplier 35,
When it is "1" (that is, during key depression), the coefficient "1" is selected and given to the multiplier 35. Therefore, during key depression, the envelope waveform data output from the adder 34 passes through the multiplier 35 without any change, and after key release, this envelope waveform data follows the dump envelope waveform data read from the memory 17. It is controlled (rapidly damped) and output from the multiplier 35.

In this way, from the multiplier 35, each envelope memory 15-17
Envelope waveform data obtained by synthesizing the envelope waveform data read from is output to the multiplier 37. The multiplier 37 multiplies the musical tone waveform data read from the waveform memory 14 by the envelope waveform data to control the amplitude envelope. The envelope-controlled musical tone waveform data output from the multiplier 37 is converted into an analog signal by the digital-analog converter 38 and then applied to the sound system 39.

In the above embodiment, the attack envelope memory 15 stores the data corresponding to the difference between the desired envelope waveform and the envelope waveform component of the musical tone waveform data stored in the waveform memory 14, but not limited to this, the desired envelope The waveform level data may be stored as it is.
However, in that case, waveform processing is performed in advance so that the envelope waveform component of the musical tone waveform data to be stored in the waveform memory 14 has a uniform level, and the musical tone waveform data having the uniformized envelope waveform component is stored in the memory 14. It should be remembered.

Further, the waveform memory 14 may store the waveform of the rising portion of the musical sound and a part of the waveform thereafter (however, a plurality of periodic waveforms). In this case, the phase accumulator 13 reads all the waveform data of the rising portion and then repeatedly reads a part of the waveforms thereafter to read the entire waveform from the start to the end of the sound generation. In addition, waveform memory
It is also possible to store only one cycle of the musical tone waveform in 14 and repeatedly read this. In this case, the lower bit (representing 0 to 2π) of the phase angle information qF output from the accumulator 13 is added to the waveform memory 14 as an address signal.

Further, the waveform memory 14 does not store the tone waveform amplitude sample data as it is, but stores the difference data between adjacent sample amplitude values, and cumulatively adds and subtracts the difference data at the time of reading to obtain the original amplitude sample. Data may be obtained.

Furthermore, in the above embodiment, the case of generating a tone waveform signal using the waveform memory has been described, but the present invention is not limited to this, and any frequency modulation calculation method (FM method), harmonic synthesis method, filter method, or the like can be used. A musical tone waveform signal may be generated by using a signal.

As described above, according to the present invention, while the plurality of different envelope signals are stored in the envelope signal storage means, the time from the generation start instruction of the musical tone to the mute start instruction is detected and detected by the detection means. An envelope signal is selected and read from the envelope signal storage means according to time, and the attenuation envelope of the musical sound from the start of muffling to the completion of muffling is controlled by this. Therefore, for example, when using the keyboard as pitch specifying means,
The envelope waveform after the key is released is selected from the envelope signals stored in the envelope signal storage means according to the length of the key pressing duration.
The envelope waveform after key release can be controlled in various ways according to the length of the key pressing duration. That is, according to the present invention, it is possible to variously control the attenuation envelope for silencing in accordance with the length of the sounding duration from the start of generation to the start of muting. Subsequent subtle changes in the attenuation envelope can be realized. Moreover, since it is only necessary to store a plurality of different envelope signals, the configuration can be simplified as compared with the case where all the musical tone waveforms are stored.

[Brief description of drawings]

FIG. 1 is an electrical block diagram showing an embodiment of an electronic musical instrument according to the present invention, and FIG. 2 is a view showing an example of envelope characteristics corresponding to various touch intensities to be stored in an attack envelope memory of the embodiment, FIG. 3 (a) is a diagram showing an example of a transient waveform to be stored in the envelope transient waveform memory of the same embodiment, and FIG. 3 (b) shows an envelope given to a musical tone waveform when envelope control by this transient waveform is not performed. The figure which shows an example, (c) is a figure which shows the example of envelope provision when performing envelope control by a transient waveform,
Is. 10 …… keyboard, 11 …… key coder, 12 …… frequency number memory, 13 …… phase accumulator, 14 …… waveform memory,
15 …… Attack envelope memory, 16 …… Envelope transient waveform memory, 17 …… Dump envelope memory, 18 …… Touch detection means, 19 …… Means for reading envelope transient waveform memory, 35, 3
7: Multiplier.

Claims (1)

[Claims] 1. A pitch designating means for designating a pitch of a musical tone to be generated and for instructing the generation start and muffling start of the musical tone, and a musical tone corresponding to a pitch designated by the pitch designating means. A musical tone waveform generating means for generating a waveform signal, an envelope signal storing means for storing a plurality of different envelope signals for controlling the envelope of the musical tone waveform signal, and a musical tone generation start instruction issued by the pitch designating means. Detecting means for detecting the time until the muting start instruction, and selecting the envelope signal stored in the envelope signal storage means according to the time from the musical sound generation start instruction detected by the detecting means to the muting start instruction Control means for reading and controlling the envelope of the tone waveform signal generated from the tone waveform generating means based on the envelope signal; An electronic musical instrument equipped with.