JP2548113B2 - Electronic musical instrument - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic musical instrument, and more particularly to a key assigner type electronic musical instrument that generates a musical tone by assigning a musical tone to a limited number of sounding channels.

2. Description of the Related Art In recent years, electronic musical instruments have a limited number of sound generation channels, and a key assigner system in which musical tones are generated is often used. A channel of such an electronic musical instrument is disclosed in, for example, Japanese Patent Laid-Open No. 58-88790. A block diagram is shown in FIG. 3 and its operation will be described.

The waveform generator 31 generates synchronous waveform data based on the note octave information. Envelope generator
32 generates an envelope signal based on the key depression information.
Here, the envelope generator 32 is configured to sequentially read the envelope waveform input in the memory from the rising portion by pressing the key and sequentially read the envelope waveform of the release portion by releasing the key. The multiplier 33 multiplies the waveform data generated by the waveform generator 31 and the envelope signal generated by the envelope generator and outputs the result as a musical tone signal.

DISCLOSURE OF THE INVENTION Problems to be Solved by the Invention However, in the above-described conventional configuration, when a new musical tone is assigned while a musical tone is being generated in the released state, the envelope immediately drops to zero as shown in FIG. A click sound may occur. As a countermeasure against this, there is a method of generating the next envelope by temporarily lowering the envelope to zero with a small time constant such that a click cannot be heard (for example, US Pat. No. 4,041,825).
In this method, there is a considerable waiting time until a musical sound is actually generated after the key is pressed, and there is a problem in actual performance.

Means for Solving the Problems In order to solve the above problems, the electronic musical instrument of the present invention starts sounding according to an instruction of a key-on signal, attenuates the volume of the sounding according to an instruction of a key-off signal, and outputs a new key-on signal. A means for accelerating the attenuation of the sound volume of the sound by an instruction, detecting that the sound volume of the sound is below a predetermined level, stopping the sound generation, and then starting sound generation based on the new key-on signal Is.

Operation According to the present invention, when a new sounding request is made to a channel that is generating a musical tone in the released state, the envelope in the already released state is sharply reduced within a range in which the click sound cannot be heard. Therefore, no clicking sound is generated. In addition, the channel actually starts sounding within a short waiting time after a sounding request is issued in order to generate a musical tone for the next sounding request when the envelope falls below a predetermined level without waiting until the envelope becomes zero. You can

EXAMPLES The present invention will be described below with reference to the drawings.

FIG. 1 shows an embodiment of an electronic musical instrument according to the present invention. In FIG. 1, 11 is a buffer memory,
Key data sent by a microcomputer or the like is stored by a write signal. Here, the key data is data including key depression information indicating ON / OFF of the key and information indicating which key is the depressed key such as note data and octave data. When the key is on, the key depression information is "1". A key data memory 12 writes input data when a pulse is applied to the WR terminal. Reference numeral 13 denotes an envelope generator, which generates an envelope signal corresponding to key depression information when a signal "O" is applied to the FD terminal. On the other hand, when the FD terminal input is the signal "1", the envelope signal is attenuated sharply but to the extent that no click sound is heard. A level detector 14 outputs "1" when the input level is equal to or higher than a predetermined level. Reference numeral 15 is a waveform generator, which generates waveform data according to key pressing information. Reference numeral 16 is an allocation control circuit, which inputs signals to K1, K2, and B terminals and generates a write pulse for the key data memory 12 from the WP terminal and a fast dump flag (hereinafter referred to as FD flag) from the FD terminal. . Here, the key depression information output from the buffer memory 11 is given to the K1 terminal, and the key depression information output from the key data memory 12 is given to the K2 terminal.

Here, the write pulse is generated when the signal “1” is applied to the K2 terminal or the signal “O” is applied to the B terminal, and the FD flag is “1” at the K1 terminal, “O” at the K2 terminal, and “1” at the B terminal. When "" is applied, it becomes "1". Reference numeral 17 denotes a multiplier, which multiplies the waveform data output from the waveform generator 15 and the envelope output from the envelope generator 13 and outputs the result as a musical tone signal.

Next, the operation of this embodiment will be described. When a key is pressed on the keyboard, the microcomputer detects it and generates a signal indicating key pressing as key data, which is written in the buffer memory 11. If, at this time, the envelope generated by the envelope generator 13 is in a fully attenuated state, the output of the level detector 14 is "O", so the assignment control circuit 16 sends a write signal to the key data memory. Is sent. With this write signal, the key data memory 12 receives the key data from the buffer memory 11 and stores it. The envelope generator 13 and the waveform generator 15 generate the envelope and the waveform data based on the key data, which are multiplied by the multiplier 17 and output as a tone signal (FIG. 2A). When the key is then turned off, this information is conveyed to the buffer memory 11 and then to the key data memory 12 and the envelope generator
13 enters the released state and begins to attenuate the envelope (Fig. 2B). When a new key is pressed here, new key data is written in the buffer memory 11. The K1, K2 and B terminals of the allocation control circuit 16 will now be described. The K1 terminal is given "1" by a new key depression. Meanwhile K2
"O" is given to the terminal by releasing the key. Further, the output of the level detector 14 is given to the B terminal, but since the envelope generated by the envelope generator 13 has just started to attenuate, the level detector 14 outputs "1". Therefore, the allocation control circuit 16 is a key data memory.
Since no write pulse is sent to 12, the old data is still stored in the key data memory 12. In addition, since the current state is a signal “1” at the K1 terminal, “O” at the K2 terminal, and “1” at the B terminal, the allocation control circuit 16 sets the FD flag to “1”.
To the envelope generator 13. Therefore, the envelope generator 13 rapidly attenuates the envelope (Fig. 2C).

The output of the level detector 14 is inverted from "1" to "O" because the envelope falls below a certain level as it decays. Then, the FD flag output from the allocation control circuit 16 becomes "O", a write pulse is generated for the data memory 12, and the data in the buffer memory 11 is transferred to the key data memory 12
, And the envelope generator 13 and the waveform generator 15 generate envelope and waveform data corresponding to the new key depression (FIG. 2D).

Here, considering the time from when a new key is pressed until the actual sound is generated, first, the envelope that is in the released state due to the old key is rapidly attenuated by the new key. The constant is set so that the click sound cannot be heard, so no click is issued. A time constant of about 2.5 ms is considered to be suitable as the time constant that gives a sharp attenuation that does not allow the click sound to be heard. The next envelope is then generated when it reaches a predetermined level by attenuation. Normally, the envelope starts from zero, so at this time the envelope immediately drops to zero from the above-mentioned predetermined level, but since the predetermined level is set to a sufficiently small level, the click sound does not sound small. Also, when the key-on is assigned immediately to the channel to which the key-off is normally assigned, it means that another channel has already generated a musical tone, so even if a small click sound is produced, masking by another musical tone is performed. Almost inaudible due to the effect. By the way, the above predetermined level varies depending on the number of sound generation channels, but when the number of sound generation channels is eight,
It is enough to set it to about 60 dB.

With the above-described configuration, it is possible to generate a musical sound corresponding to a new key depression without a click sound in any case.

Although FIG. 1 shows the configuration for one channel, it goes without saying that these devices may be used in a time division manner to form a plurality of channels. Further, the detection level of the level detector 14 may be variable by external control or the like, and the inclination of the envelope when the FD flag is "1" may be switchable by external control or the like. Further, the data stored in the buffer memory 11 and the key data memory 12 is not limited to the key pressing information, the note data, and the octave data, but the key pressing strength, the speed, or the information regarding the tablet or the like is stored. By doing so, these various data can be switched in synchronization with the actual generation of musical tones.

As described above, according to the present invention, the sounding is started by the instruction of the key-on signal, the volume of the sounding is attenuated by the instruction of the key-off signal, and the attenuation of the sounding volume is accelerated by the instruction of the new key-on signal. By providing a means for detecting that the volume of the above-mentioned pronunciation becomes lower than a predetermined value and stopping the above-mentioned pronunciation and starting the pronunciation based on the new key-on signal, the old musical sound is still generated in the released state. Even when a new musical tone is assigned to the existing channel, the old musical tone can be attenuated without a click sound, and the newly assigned musical tone can be quickly generated.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an electronic musical instrument according to an embodiment of the present invention, FIG. 2 is a waveform diagram of an envelope signal generated in the electronic musical instrument shown in FIG. 1, and FIG. 3 is a block showing a conventional example. FIG. 4 and FIG. 4 are waveform diagrams of envelope signals of an electronic musical instrument in the conventional example. 11 ... Buffer memory, 12 ... Key data memory, 13 ...
… Envelope generator, 14 …… Level detector, 15 …… Waveform generator, 16 …… Allocation control circuit, 17 …… Multiplier.

Claims (1)

(57) [Claims] 1. A sound is started by an instruction of a key-on signal,
Attenuate the volume of the above pronunciation by instructing the key-off signal,
A new key-on signal is issued to accelerate the attenuation of the sound volume of the above-mentioned sound, and when the sound volume of the above-mentioned sound is detected to fall below a predetermined level and the above-mentioned sound is stopped, the sound generation based on the new key-on signal is started. Electronic musical instrument having means for performing.