JPS5855437Y2 - electronic musical instruments - Google Patents

Description

[Detailed description of the invention] The present invention distributes a key press signal transmitted by an encoded digital signal to a single or multiple sound source circuits, reads out waveform information of the tone range corresponding to the key press signal, and The present invention relates to an electronic musical instrument for processing a musical sound waveform of a frequency corresponding to a key.

In recent years, in sound source devices for electronic musical instruments, one period of a required musical sound waveform is stored in a waveform memory circuit in advance, and the waveform stored in the waveform memory circuit is converted into a sound source clock signal having a repetition period proportional to the scale frequency. A system has been proposed in which a musical sound waveform of each scale frequency is obtained by reading the sound.

According to this method, in order to faithfully reproduce complex musical sound waveforms, especially natural musical instrument sounds, the memory capacity of the waveform memo circuit becomes large.

Furthermore, if the above-mentioned sound source device is constructed using the conventional one-key, one-engine generator method, the device itself becomes large and complicated.

Therefore, in order to simplify the former, the present applicant
A new method was proposed in No. 05861 and Japanese Patent Application No. 139935/1982.

These methods use linear approximation to the required musical sound waveform, and calculate one period at irregular intervals (49-105861) or at equal intervals (49-1399).
35) and store the waveform slope, amplitude change, and time information (49-105861) in each section.

As a result, the memory capacity can be significantly reduced and the number of quantization steps can be increased with a small memory capacity.
This has advantages such as being able to reduce quantization noise.

” - Patent Application No. 105861/1973 and Patent Application No. 4/1973
Although the sound source device disclosed in No. 9-139935 is advantageous in almost faithfully reproducing the sounds of natural instruments, in order to achieve the desire unique to electronic musical instruments to play multiple sounds simultaneously, it is necessary to use the waveform memory described above. Although a plurality of circuits must be provided, the device becomes larger.

Therefore, a proposal for a master regulation was made in Japanese Patent Application No. 79673/1983 filed by the present applicant.

In other words, according to this method, 1 in the required musical sound waveform.
By dividing the period into multiple sections and storing information on the slope and amplitude change of the waveform in each divided section, and reading out the information in a time-division manner, each waveform with a different frequency can be created based on one waveform forming information. can be obtained at the same time.

In this way, multiple sounds can be generated simultaneously without increasing memory capacity.

In addition, Japanese Patent Application No. 50-96035, also proposed by the present applicant, proposes improvements to the key assigner system that allocates key press and key release signals sent by encoded digital signals to the necessary sound source circuits. It was.

Furthermore, in the case of natural musical instrument sounds, the frequency spectrum included in the musical sound waveform generated by the sound changes in the tonal range, and there is a problem in that it is difficult to simply approximate this with a single musical sound waveform.

An object of the present invention is to provide an electronic musical instrument equipped with a sound source device that can faithfully reproduce natural musical instrument sounds by taking into account the fact that the frequency spectrum of a musical sound waveform changes depending on the range.

In order to achieve the above object, the electronic musical instrument of the present invention divides the musical range into a plurality of octaves, and sequentially increases the memory capacity corresponding to each divided octave as the octave becomes lower; Means for further dividing a desired musical sound waveform of each octave into a plurality of sections and storing information on the waveform slope and amplitude change in each section in a memory circuit corresponding to the octave, and corresponding to key presses and key releases. a means for generating a key code signal from the key code signal generating means; a means for generating the memo note reading frequency according to the key code signal from the key code signal generating means; and a musical sound waveform data corresponding to the octave pressed by the key is stored in the memory circuit. means for selecting a selected memory circuit, means for reading musical tone waveform data from the memory circuit selected by the selecting means at the memory read frequency, and temporarily storing musical waveform data read from the memory circuit by the reading means. and means for forming a tone waveform from the tone waveform data stored by the storage means.

The present invention will be described in detail below with reference to examples.

FIG. 1 is an explanatory diagram showing the configuration of an embodiment of the present invention.

In the figure, a key signal from a keyboard 1 is divided into two channels through a plurality of, for example, two key assigners 2□ and 22, depending on the sound range.

The key information from the key assigners 2□ and 2□ is shown as a pitch name code on line 1□-1, an octave code as 12-1, and key name information as line 13-1.

The last key name information is information indicating whether the key assigner has captured the key information.

Of these, the octave code is generated by operating the sequential pulse generator IB with the clock from the time division clock generator 17, and the sequential pulse T1 is applied to the gate circuit 3□ via the line 17-1. The signal is time-divided and provided to the octave selection circuit 23 via the octave pass line 18.

The octave selection circuit 23 is constituted by a tecoder circuit, and operates a memory having a number of words corresponding to the range shown in the memory circuit 20 described below.

The memory circuit 20 stores one period of waveform data for each octave.
Each octave has a number of words corresponding to its octave.

That is, the output from the sound source device 26□ specifies the memory address of each tone range whose number of words is changed as shown below.

The number of bits of the supply line from the sound source device in this case is also shown.

Next, the key assigner 21 applies the pitch name code 11-1 to the pitch name selection circuit 4□, which selects the pitch name clock corresponding to the pitch name code from among the clock frequencies from the mask oscillator 14.

The mask oscillator 14 has a range of 61 keys C2 to C2 in Table 1.
If it is C7, a clock of mXn×(C7 to C6#) will be generated.

Here, m is the highest range (C7 to C6#) as shown in Table 1.
), where n indicates the number of clocks in one cycle of the next waveform forming circuit 5□, which is frequency-divided by n by this waveform forming circuit 51 and given to the address counter 6□.

This address counter 6□ is 4 x 32 if m=4
Clock m×(C7 to C6
#) is used for counting.

The output of the address counter 61 is passed through the gate circuit 9□ to the time division clock T1. T
Give 2.

The signal from the address counter 6□ is time-divided by this time division clock T1 and is applied to the memory circuit 20 through the address line 15 along with the signals of other channels.

A synchronization pulse generation circuit 10, which branches the output of the address counter 6□, generates one pulse for each cycle of the address counter 6□ and supplies it to a synchronization circuit 24, which will be described later.

Further, if necessary, the complement circuit 19 stores a half cycle of the waveform in the memory circuit 20, and reads out the waveform data of this half cycle repeatedly to complete one cycle.

It is possible to perform the same operation as in the case where the data is stored.

In this manner, a memory address is designated according to the address counter 6, and the memory is designated by the octave code, so that the memory portion of the number of words corresponding to the octave is read out with the time division clock T1.

As a result, the first
As shown in the table, as the octave becomes lower, the number of words increases by 2m, so octave frequency division is performed.

The data read out at this cycle is applied to an adder circuit 22 via a gate circuit 21.

When a certain key is captured by the key assigner 21, the gate circuit 21 transmits the corresponding time division clock T1 to the gate circuit 241 from the synchronization circuit 24□ within the dotted line frame 24.
is applied to the gate circuit 21 through the gate circuit 21 to turn on the data from the memory circuit 20.

The synchronization circuit 24□ receives an on/off signal from the tone tablet 25, provides a signal indicating whether the key assigner 2□ has captured the key code from the line 13-1, and also receives a synchronization signal from the synchronization pulse generation circuit 10□. The signal is line 16-1
More given.

This synchronization circuit 242 is composed of a D type flip-flop, which is cleared by a signal from line 13-1, a control signal for the tone tablet 25 is given to the D terminal, and synchronization from line 16-1 is performed. When a signal is applied to the clock terminal, "1" is written in the flip-flop, applied to the gate circuit 24□, and the corresponding time division clock T1 is applied to the gate circuit 21.

In the adder circuit 22, as shown in FIG. 2, when the memory circuit 20 is a combination of a plurality of memory circuits, the gate circuit 21 is also configured to perform addition via a plurality of gates.

The memory output data is supplied from the adder circuit 22 to the first latch circuit 8 via the data bus line 14 and its corresponding time division data.

That is, since the latch circuit 8□ performs latching using the same pulse T1 as the time division pulse of the gate circuit 9, data corresponding to this channel is latched.

This data is transferred to the second latch circuit 7□ by the waveform forming circuit 5□.
The waveform data is latched in synchronization with the musical sound waveform by the clock output from the waveform forming circuit 5□.

In this waveform forming circuit 51, a waveform template is generated from the memory circuit 20 in accordance with the count value of the address counter 6□.
The sound waves are sequentially read out and a musical sound waveform is obtained.

The musical sound waveform of the waveform forming circuit 5□ is input into the multiplier circuit 11□, and by adding the envelope waveform A1 to it, it is made into a musical sound waveform close to a natural sound, and then inputted to the analog multiplexer 131 as an analog musical sound waveform through the D-A converter 121. , key assigner 2, the octave code 1°-1 is used to allocate the cutoff frequency to the filter circuit 15 corresponding to each range, and guide the sound to the sound system 16.

The above has described the structure and operation of the first channel, which is important from the memory circuit 20, which is a common part with the sound source circuit 26□, etc., including the key assigner 2□, the gate circuit 31, and the waveform forming circuit 6□. The structure and operation of the second channel, which includes the sound source circuit 262, etc., including the circuit 3° and the waveform forming circuit 6□, and the memory circuit 20, which is a common part, are completely the same as the first channel, and the corresponding structure is indicated by the subscript 1.2. It is shown by .

The difference is that the key code is divided into two by the key assigner and the contents of the corresponding memory circuit are assigned to each part, so that the waveform information corresponding to the key code of the key can be extracted separately or in combination.

In the example, the above-mentioned Japanese Patent Application No. 105861/1986 was used,
Although the configuration is such that the two channels are provided in a time-sharing manner, the feature is that it is a single memory circuit 20 rather than a mere 2-type configuration.

For this purpose, the latch circuits 81, 8□, which temporarily store the synthesized musical sound waveform data from the adder circuit 22, are connected to the sound source circuit 26. ,
26□, and the gate 21 in front of the adder circuit 22 is controlled by a synchronization circuit 24.

In the embodiment, two channels are provided by octave division, but the present invention is not limited to this and can be provided with a plurality of channels.

In this case, it is even more advantageous.

Also, octave selection circuit 23, note name selection circuit 44, 4□
By appropriately changing the key information given to the key assigners 2□ and 2□, arbitrary block division can be easily performed.

As explained above, according to the present invention, it is sufficient to divide the required musical sound waveform into a plurality of tonal ranges and store information on the waveform slope and amplitude change in each of the divided memory circuits. Since it is possible to freely set the frequency spectrum that changes depending on the sound range in memory, it is possible to realize a sound that is closer to the sound of a natural instrument than a single-channel electronic musical instrument.

[Brief explanation of drawings]

FIG. 1 is an explanatory diagram showing the configuration of an embodiment of the present invention, and FIG. 2 is a detailed diagram of the main parts of the embodiment. In the figure, 1 is a keyboard, 20,
2□ is the key assigner, 31, 3□ is the G-F circuit, 40
, 4□ is a pitch name selection circuit, 50, 5□ is a waveform forming circuit, 6
□, 6□ are address counters, 7□, 72.8□, 8
□ is a latch circuit, 9□, 9□ are gate circuits, 10. ,1
0□ is a synchronization pulse generation circuit, 11. , 11□ is a multiplication circuit, 12. , 12□ is a DA converter, 130, 13□ are analog multiplexers, 14 is a master oscillator, 15 is a filter circuit, 16 is a sound system, 17 is a time division clock generation circuit, 18 is a sequential pulse generator, 19 is a complement circuit , 20 is a memory circuit, 21 is a gate circuit, 22 is an addition circuit, 23 is an octave selection circuit, 24 is a gate circuit, 242 is a synchronization circuit, 25 is a tone tablet, 26
□ and 26□ indicate sound source devices.

Claims (1)

[Scope of utility model registration request] Means for dividing the musical range into a plurality of octaves, increasing the memory capacity corresponding to each octave in sequence as the octave becomes lower, and further dividing the desired tone waveform of each octave into a plurality of sections. means for dividing and storing information on the slope and amplitude change of the waveform in each section in a memory circuit corresponding to an octave; means for generating a key code signal in response to key presses and key releases; and the key code. means for generating the memory read frequency based on a key code signal from the signal generating means; means for selecting from the memory circuit a memory circuit in which musical sound waveform data corresponding to the octave of the pressed key is stored; and selection by the selecting means. means for reading musical waveform data from the memory circuit at the memory read frequency; means for temporarily storing musical waveform data read from the memory circuit by the reading means; and means for temporarily storing musical waveform data read from the memory circuit by the reading means; An electronic musical instrument characterized by comprising means for forming a musical sound waveform.