JPH0423276B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electronic musical instrument equipped with a sostenuto pedal function.

The existence of sustain pedals or switches in electronic musical instruments is well known. This sustain pedal is for sustaining all keys on the keyboard, and when this pedal (or switch) is operated, sustain is applied to any key after the key is released. Therefore, selective sustain control such as applying sustain to only a specific key and not applying sustain to other keys has been impossible. For example, it is often required in music to apply sustain to one of the melody or accompaniment sounds, but not to apply sustain to the other, but when playing the melody and accompaniment, as in a single-keyboard electronic instrument, Conventional sustain pedals have not been able to meet such demands when both are played on the same keyboard.

This invention was made in view of the above points,
The present invention aims to provide an electronic musical instrument that can sustain only one or more specific keys and not sustain other keys.
This objective is achieved by an electronic musical instrument that has a function similar to the sostenuto pedal on a piano. The electronic musical instrument according to the present invention includes: a key press detection means for detecting a key pressed on a keyboard; a sostenuto operator; a sostenuto signal forming means for outputting a sostenuto signal corresponding to the key being pressed when the operation of the child is started until the operation of the operator is completed; a musical tone generating means for generating a corresponding musical tone signal and controlling opening/closing of the musical tone signal corresponding to each pressed key according to the output of the pressed key detecting means and the sostenuto signal, opening/closing control in the musical tone generating means; is to attenuate the musical tone signal at a first rate when the output of the key press detection means indicates that the key is being pressed; When a sostenuto signal is generated, the musical tone signal is attenuated at a second rate, and when the output of the key press detection means indicates a key release and the sostenuto signal corresponding to that key is not generated, the musical tone signal is attenuated at the second rate. This control is characterized in that the musical tone signal is attenuated at a third rate that is considerably faster than the first and second rates.

According to this invention, the attenuation of musical tone signals is controlled at three rates. First, if the key to be controlled according to the sostenuto signal is kept pressed, the musical tone signal is attenuated at the first rate, and then the key is released and the sostenuto signal corresponding to that key is generated. If the key is released, the musical tone signal is attenuated at the second rate, and finally, if the key is in a released state and no sostenuto signal corresponding to that key is generated, the musical tone signal is attenuated at the third rate. Therefore,
It is possible to control the attenuation of a musical tone according to a sostenuto operation, and even when controlling the attenuation of a musical tone according to a sostenuto operation, the first rate is set during the key press and after the key is released. The attenuation rate is different between the two rates and the second rate. Also,
If the sostenuto operation is released or not performed, the decay rate after key release is the third rate, which is considerably faster.

Embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

In FIG. 1, a keyboard 10 includes a plurality of keys, and a pressed key is detected by a key press detection circuit 11. The sound generation assignment circuit 12 is for allocating the sound generation of a musical tone corresponding to a pressed key to one of a plurality of musical sound generation channels.
This allocation is performed according to the signal given from 1 to 1. The key press detection circuit 11 and the sound generation assignment circuit 12 may have any configuration, and their typical configurations are well known, so the details will not be specifically explained here. The sound generation assignment circuit 12 generates a key code KC representing the key assigned to each channel.
and a key-on signal KON indicating whether the key is currently being pressed or released, corresponding to each channel. These key codes KC and key-on signals KON are outputted in a time division multiplexed manner. An example of time division time slots (channel timing) corresponding to each channel is as follows.
It will look like the figure. In FIG. 2, φ is a system clock pulse that controls time division timing. Tch1 to Tchn are channel timing pulses synchronized with each channel timing (1 to n).

A sostenuto signal forming circuit 13 is provided in association with the sound generation assignment circuit 12. The sostenuto signal forming circuit 13 is for sustaining the sound of the key being pressed when the sostenuto pedal 14 is started. The sostenuto signal forming circuit 13 includes the output of the sostenuto switch 14S that is linked to the sostenuto pedal 14, and the key-on signal output from the sound generation assignment circuit 12.
KON is supplied, and when the sostenuto pedal 14 is started, the key-on signal KON is supplied.
The value indicates the key press (it is “1”)
A sostenuto signal SST is generated corresponding to the channel. This sostenuto signal SST continues as long as the sostenuto pedal 14 is operated (time-divisionally in accordance with its channel timing).
generated. The sostenuto signal SST is applied to the OR circuit 15 together with the key-on signal KON outputted from the sound generation assignment circuit 12. The output of the OR circuit 15 is used as the key-on signal KON' to the musical tone generating circuit 1.
given to 6. Even if the value of the key-on signal KON corresponding to the actual key press and release falls to "0" due to the key release, the sostenuto signal SST corresponding to that channel is generated (it is "1"). ), then the OR circuit 15 to the musical tone generation circuit 16
The key-on signal KON' applied to the key-on signal KON' continues to be "1" indicating that the key is kept pressed. As a result, it is possible to continue the generation even after the key is released, as if the key had been kept pressed.

An example of the sostenuto signal forming circuit 13 is shown in FIG. The output of the sostenuto switch 14S is applied to a differentiation circuit 18 and an AND circuit 19 via a synchronization circuit 17. The synchronization circuit 17 is for synchronizing the rise and fall timings of the output signal of the sostenuto switch 14S with a predetermined channel timing 1. timing signal T1
(see Figure 2). For example, when the output signal of the sostenuto switch 14S rises to "1" as shown at 14S in FIG. X rises to "1" (see X in Figure 2). When the sostenuto pedal 14 (FIG. 1) is operated, the sostenuto switch 14S is turned on and its output signal becomes "1". While the operation of sostenuto pedal 14 continues, switch 1
4S remains on and the output remains "1". When the pedal 14 is released, the switch 14S is turned off and its output falls to "0". switch 1
When the output of 4S falls to "0", the output X of the synchronization circuit 17 also falls to "0" in synchronization with the timing signal T1, similarly to when it rises.

The differentiating circuit 18 is a circuit that outputs "1" as the output signal Y only during one cycle of each channel timing in synchronization with the rise of the signal X, and is controlled by the timing signal T1. As shown by Y in FIG. 2, the signal Y becomes "1" only during one cycle of the channel timings 1 to n in synchronization with the rising edge of the signal X (that is, at the start of operation of the sostenuto pedal 14). The output signal Y of the differentiating circuit 18 is given to an AND circuit 20. The other input of the AND circuit 20 is connected to the sound generation assignment circuit 12 (first
The key-on signal KON is given from (Fig.). The output of the AND circuit 20 is applied to a shift register 22 via an OR circuit 21. shift register 22
is n stages/1 bit (n is a number corresponding to the number of channels), and is shifted and controlled in synchronization with the time-division channel timing according to the system clock pulse φ. The output of this shift register 22 is circulated and held via an AND circuit 19 and an OR circuit 21, and is output as a sostenuto signal SST. The output X of the synchronization circuit 17, that is, a signal corresponding to the operation of the sostenuto pedal 14 is applied to the other input of the AND circuit 19.

When the sostenuto pedal 14 is not operated, the signal X is "0", the AND circuit 19 is inoperable, and the contents of all stages of the shift register 22 are cleared. Therefore, no sostenuto signal SST is generated. When the operation of the sostenuto pedal 14 is started,
Each channel timing 1 to n is determined by signal Y.
The AND circuit 20 is enabled only during one cycle, and the state of the key-on signal KON of each channel during that period is taken into the shift register 22. When the signal Y falls, the AND circuit 20 is disabled and the new acquisition of the key-on signal KON is prohibited. On the other hand, the sostenuto pedal 14
During the operation, the AND circuit 19 is enabled by the signal
It is held at 2. Therefore, the sostenuto signal SST corresponding to the channel that was being depressed when the sostenuto pedal 14 was started becomes "1". This sostenuto signal SST is a time division multiplexed signal synchronized with the timing of each channel, similar to the key-on signal KON. A sostenuto signal corresponding to the channel that was being pressed when the sostenuto pedal 14 was started.
SST is “1” while the pedal 14 is operated.
hold. When the foot is released from the pedal 14, the signal X falls to "0", the contents of the shift register 22 are cleared, and the sostenuto signal SST disappears.

As mentioned above, the channel timings of the sostenuto signal SST and the key-on signal KON match, so even if the key-on signal KON becomes "0" when the key is released, the sostenuto signal SST corresponding to that channel is generated. If there is,
The key-on signal KON' output from the OR circuit 15 in FIG. 1 maintains "1" as if the key press continues. In the musical tone generation circuit 16, the key-on signal KON' is used to control the generation of musical tones in response to key presses and key releases.

In the present invention, any method can be used as the musical tone generation method and sound generation control method. 1st
The figure shows an example in which musical tones are generated by a frequency division method. Key code of each channel outputted from the sound generation assignment circuit 12 in a time-sharing manner
KC is given to the frequency division ratio ROM23. Division ratio
The ROM 23 stores frequency division ratio data for setting musical tone frequencies in advance for each key.
Predetermined frequency division ratio data is read out according to the key code KC. The frequency division ratio data read from the frequency division ratio ROM 23 is given to the musical tone generation circuit 16.
The musical tone generation circuit 16 has each musical tone generation channel.
Circuits corresponding to CH1 to CHn are provided in parallel. Although only the channel CH1 will be illustrated and explained as a representative, the same applies to the other channels CH2 to CHn. In addition, the channel of the musical tone generation circuit 16
CH1 to CHn are channel timings 1 to n
It corresponds to each.

In channel CH1, latch circuit 24
is the frequency division ratio data of the key assigned to each channel given from the frequency division ratio ROM 23 and the key-on signal of each channel given from the OR circuit 15.
This is for latching the KON′ that corresponds to its own channel. For this purpose, a timing signal Tch1 (see FIG. 2) corresponding to channel timing 1 is input to the load control input (L) of the latch circuit 24 of channel CH1. Timing signals Tch2 to Tch2 corresponding to the respective channel timings 2 to n are applied to the latch circuits in other channels CH2 to CHn as well.
Tchn is input. The frequency division ratio data latched in the latch circuit 24 is applied to the variable frequency division circuit 25. The variable frequency divider circuit 25 divides the frequency of CP into the sound source master clock pulse at a frequency division ratio corresponding to the input frequency division ratio data, and outputs a sound source signal with a frequency corresponding to the key assigned to the channel. do. This sound source signal is input to the switching circuit 26.

On the other hand, the key-on signal KON'1 latched by the latch circuit 24 (of KON', the one corresponding to channel CH1 is shown as KON'1) is applied to the envelope generator 27. When implementing the function of a sostenuto pedal, the amplitude envelope of the musical tone is typically a percussive envelope that imitates the timbre of a piano. Percussive envelopes are normally used for key presses and key releases as shown in Figure 4a.
It exhibits the characteristics shown in . In other words, in response to a key press, the sound rises rapidly to a peak level (this state is called attack), then gently decays (this state is called sustain), and in response to a key release, it rapidly decays to silence ( This state is called a dump). Generally speaking, applying sustain by operating the sustain pedal (or dump pedal) means maintaining the sustain state without changing to the dump state in response to key release. By operating the sostenuto pedal according to the present invention, it is possible to maintain the same sustain state as described above. However, the difference is that by operating the sustain pedal, all keys can be sustained, whereas with the sostenuto pedal, sustain can only be applied to a specific key (the key pressed at the beginning of pedal operation).

The envelope generator 27 responds to the state of the input key-on signal KON'1 by "attack" or "attack".
Generates a percussive envelope signal EV with "sustain" and "dump" characteristics. That is,
When the key-on signal KON'1 rises to "1", an "attack" part is generated, and then "sustain" is maintained while KON'1 remains "1",
When the key-on part KON'1 falls to "0", it becomes "dump". When the sostenuto pedal 14 is not operated, the key-on signal KON'1 corresponds to the key-on signal KON corresponding to actual key depression and key release, and the envelope signal EV generated from the envelope generator 27 is as shown in FIG. As shown in Fig. a, "dump" occurs immediately in response to key release. In the switching circuit 26, this envelope signal
Control the amplitude envelope of the sound source signal according to EV. Therefore, it is normally possible to perform without sustain. If the sostenuto pedal 14 is operated while the key assigned to channel CH1 is being pressed, the sostenuto signal SST is generated in response to channel timing 1 as described above.
Key-on signal corresponding to channel CH1
KON'1 remains at "1" as long as the pedal 14 is operated even after the key is released. Therefore, in that case, as shown in FIG. 4b, the "sustain" is maintained even after the key is actually released, and when the pedal 14 is subsequently released, the sound becomes "dump" and the sound is muted.
Further, for a key that is pressed after the start of operation of the sostenuto pedal 14 and while the operation continues, the key-on signal KON is not loaded into the shift register 22 (FIG. 3), and therefore the channel assigned to the key is not loaded. Sostenuto signal corresponding to SST
The envelope does not occur, and as shown in FIG. 4a, the envelope is the same as a normal key press/release operation without sustain.

As described above, it is possible to apply sustain only to the key that is being pressed when the sostenuto pedal 14 starts operating, and not to apply sustain to the other keys. Each channel
The sound source signals output from CH1 to CHn are supplied to a mixing and tone color circuit 28, mixed, and given a tone color, and then supplied to a sound system 29.

By the way, in the pronunciation assignment process, the channel whose key was released the earliest is designated as a truncated channel, and a new pressed key is assigned to this truncated channel. In this case, it is not preferable that a channel whose sustain state is maintained by operating the sostenuto pedal 14 be designated as a truncate channel, and it is desirable to prohibit truncation of such a channel. Therefore, the sostenuto signal SST generated from the sostenuto signal forming circuit 13 is also given to the sound generation assignment circuit 12, and the sostenuto signal
It acts on the sound generation allocation circuit 12 to prohibit truncation of the channel where SST is occurring.

FIG. 5 shows an example of the sound generation assignment circuit 12 equipped with a truncate prohibition function. The details of such a sound generation assignment circuit are known from Japanese Patent Laid-Open No. 51-21813, etc., so only an outline thereof will be explained below. The key code memory 30 stores the key code KC of the key assigned to each channel and outputs it in a time-division manner, and includes, for example, a circular shift register.
The assignment control circuit 31 receives the key code of the pressed key given from the pressed key detection circuit 11 and the key code memory 3.
Compare the key code KC stored in 0,
Based on this comparison, a process of assigning a new pressed key to one of the channels is performed. A truncate channel designation signal TR is given from the truncate signal generation circuit 32 to the assignment control circuit 31, and when a new pressed key is to be assigned, the control circuit 31 issues a set signal corresponding to the channel designated by this signal TR. Generates SET. Based on this set signal SET, the key code KC of the new pressed key is stored in the key code memory 30. Furthermore, within the assignment control circuit 31, a key-on signal KON representing the key press or release of the key assigned to each channel is stored and output in a time-division manner.

n-stage shift register 33, adder 3
4. The gate 35 is for detecting the key release order, and counts up the contents of the channel in which the key has been released every time a new key release is detected in any channel. When a new key release is detected, the assignment control circuit 31 outputs a new key off signal NKOF during a period in which all channel timings 1 to n go through one cycle, and the adder 34 increments the contents of each channel by 1. . The control input of gate 35 has a key-on signal.
A signal obtained by inverting KON by a NOR circuit 36 is given. Therefore, at the channel timing during key depression, the gate 35 is disabled and the output of the adder 34 is prohibited. At the timing of the channel where the key is released, the gate 35 is enabled, and the output of the adder 34 is given to the shift register 33 and held there. In this way, the count contents of the channels whose keys have been released are incremented every time a new key release is detected in any channel, and the channel holding the maximum value in the shift register 33 is the oldest. This indicates the channel for which the key has been released. The truncate signal generation circuit 32 detects the maximum value among the count values of each channel held in the shift register 33, and outputs the truncate channel designation signal TR at the timing of the channel holding the maximum value.

A sostenuto signal SST is applied to the NOR circuit 36 for truncate prohibition control. The signal SST is "0" in a channel for which sustain is not maintained by the sostenuto pedal 14, and when the key assigned to that channel is released, the signal SST is "0" due to "0" of KON and "0" of SST. The output of the NOR circuit 36 becomes "1",
Gate 35 is enabled and counting for truncation control is now possible. The signal SST is "1" in the channel where the sustain is maintained by the sostenuto pedal 14, and even if the signal KON becomes "0" due to the release of the key assigned to that channel, the NOR circuit 36 is not activated. The output does not become "1" but remains "0". Therefore, counting for truncate control is prohibited.

In addition, in the above embodiment, the normal key-on signal KON
The OR logic of the and sostenuto signal SST is used as the key-on signal KON' for sound production control, and the envelope generator 27 is controlled as if the key press is sustained. Signal KON and sostenuto signal SST
are given to the envelope generator separately, and as shown in Figure 4c, after the key is released, the sostenuto-specific rate is used (at a rate different from the normal sustain rate).
It may also be attenuated. Further, in the above embodiment, the present invention is applied to an electronic musical instrument using a sound generation assignment circuit, but the opening/closing circuit provided for each key controls opening/closing of the sound source signal of a predetermined frequency corresponding to each key. It is possible to apply the present invention to an electronic musical instrument using the system, in which case a register for storing a sostenuto signal is provided for each key, similar to the shift register 22 in FIG. 3, and the output of this register (sostenuto signal ) and the key switch output of each key to control the opening/closing circuit for each key. It is also possible to use a push-button switch as the sostenuto operator, in which case the first press of the switch turns the sostenuto on, the second press of the switch turns the sostenuto off, and the sostenuto is turned on. A display device may also be provided for displaying the information.

As explained above, according to the present invention, it is now possible to apply sustain to only a specific key in an electronic musical instrument. For example, when playing a melody and an accompaniment together on a single keyboard, sustain can only be applied to the accompaniment note. It becomes possible to perform operations such as not applying sustain to the melody sound, improving playability.

In addition, when controlling the attenuation of a musical tone in response to a sostenuto operation, the attenuation rate is made different between the first rate and the second rate while the key is being pressed and after the key is released. There is a difference between the sostenuto control during the key press and after the key is released, which has the excellent effect of improving the ability to express musical tones.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of an electronic musical instrument according to the present invention, FIG. 2 is a timing chart showing an example of time-division channel timing and various signals in the embodiment, and FIG. 3 is a timing chart showing an example of the time-division channel timing and various signals in the embodiment. A circuit diagram showing an example of a sostenuto signal forming circuit; FIG. 4a is a diagram illustrating the state of a normal envelope signal; FIG. FIG. 5 is a block diagram schematically showing an example of a sound generation assignment circuit equipped with a truncate function. 10...Keyboard, 11...Key press detection circuit, 12...
...Sound generation assignment circuit, 13...Sostenuto signal forming circuit, 14...Sostenuto pedal, 14S...
...Sostenuto switch, 16...Music tone generation circuit, 26...Opening/closing circuit, 27...Envelope generator, KON...Key-on signal, SST...Sostenuto signal.

Claims (1)

[Scope of Claims] 1. A keyboard comprising a plurality of keys, a pressed key detection means for detecting keys pressed on the keyboard, a sostenuto operator, and an output of the pressed key detection means and the sostenuto operator. a sostenuto signal forming means for outputting a sostenuto signal corresponding to the key being pressed when the operation of the sostenuto operator is started until the operation of the sostenuto operator is completed; musical sound generating means for generating a musical tone signal corresponding to a pressed key in accordance with an output of the means, and controlling opening/closing of the musical tone signal corresponding to each pressed key in accordance with the output of the pressed key detecting means and the sostenuto signal; The opening/closing control in the musical sound generating means includes:
When the output of the key press detection means indicates that the key is being pressed continuously, the musical tone signal is attenuated at a first rate, and the output of the key press detection means indicates that the key has been released and the sostenuto signal corresponding to the key is attenuated. is occurring, the musical tone signal is attenuated at the second rate, and when the output of the key press detection means indicates a key release and the sostenuto signal corresponding to that key is not generated, the musical tone signal is attenuated at the first rate. and a control that attenuates the musical tone signal at a third rate that is considerably faster than the second rate. 2. The sostenuto signal forming means corresponds to a circuit that generates a pulse of a predetermined time width in response to the start of operation of the sostenuto operator, and one or more pressed keys detected by the pressed key detection means based on this pulse. 2. The electronic musical instrument according to claim 1, further comprising a memory circuit for storing each of the sostenuto signals, and a circuit for clearing the memory of the memory circuit when the operation of the sostenuto operator is completed. . 3. A keyboard comprising a plurality of keys; a key press detection means for detecting a key pressed on the keyboard; and based on the output of the key press detection means, a newly pressed key is selected from one of a plurality of musical sound generation channels. a key code indicating the key assigned to each channel and a key-on signal indicating whether the key is being pressed or released; truncate means for controlling the sound generation assignment means to detect a key to which a released key is assigned as a truncate channel and to assign a newly pressed key to the truncate channel; a sostenuto operator; and a sostenuto operator. a sostenuto that outputs a sostenuto signal in response to the output and the key-on signal until the operation of the sostenuto operator ends, corresponding to the channel to which the key that was being pressed when the operation of the sostenuto operator was started; a signal forming means; a musical sound generating means for generating a musical tone signal corresponding to a key assigned to each channel based on the key code, and controlling opening/closing of the musical tone signal of each channel according to the key-on signal and the sostenuto signal; An electronic musical instrument, characterized in that the truncation means prohibits the detection processing for the channel in which the sostenuto signal is generated.