JPS6022188A - Sound source apparatus for electronic musical instrument - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention enables digital control of the waveform and period of the sound source signal output, with a simple configuration! J This invention relates to a sound source device for an electronic musical instrument suitable for LSI implementation.

(2) Prior Art and Problems Conventionally, in sound source devices for electronic musical instruments, a clock signal with a frequency corresponding to the pitch of a musical tone signal is divided into multiple steps, and multiple types of sound source signal outputs having an octave relationship with each other are output. It has gained. However, in the so-called "branching system" mentioned above, the output signal waveform is a rectangular wave with a duty ratio of 50%, and as is generally well known, the structure of the harmonic spectrum is simple, and the sound source of an electronic musical instrument However, it had the disadvantage of lacking effective overtone components.

As a means to improve such points, for example, the sound source 18
In order to change the duty ratio of the signal output waveform, we use a waveform output that is the AND of the output signals of each stage of the frequency divider circuit, and a comparator circuit that successively compares the output signal of each stage of the frequency divider circuit with the set value. Although it is conceivable that a sufficient output waveform can be obtained and that the circuit configuration becomes complicated, both methods have the drawbacks. It is also conceivable to use a branch system and obtain output waveforms with different duty ratios by using the output signals of a sequential pulse generator such as a ring kakunta and logically ORing the output signals of each stage. A large number of OR gates are required depending on the number of stages of the pulse generator, and the circuit configuration becomes complicated to control waveform selection, making it difficult to implement as an LSI.

(3) Purpose of the Invention The present invention has been made in view of the above-mentioned points, and provides a method for appropriately selecting only the pulses corresponding to the changing points of the sound source signal output waveform from among the output signals of the sequential pulse generator. By using a control circuit, an effective sound source signal can be generated with a simple configuration, and the number of stages of the sequential pulse generator can be reduced to 1/2' without reducing the 'a' of the effective output waveform. It is an object of the present invention to provide a sound source device for an electronic musical instrument that is particularly suitable for LSI implementation using a method that can be used in a dark manner.

(4) Structure of the Invention In order to achieve the above-mentioned object, the sound source device of Kojikuriki of the present invention includes a sequential pulse generator that generates sequential pulses by inputting a clock signal corresponding to a musical tone frequency, and a sequential pulse generator that generates sequential pulses by inputting a clock signal corresponding to a musical tone frequency. a selection control circuit that receives an output signal of the device and a selection control signal as input and selects a pulse corresponding to a changing point of the sound source signal output waveform; and a selection control circuit that receives the output signal of the selection control circuit as input and generates a sound source signal by changing the state. The apparatus is characterized in that it is equipped with a signal generating circuit, and is capable of controlling the output signal waveform of the signal generating circuit, and further includes a counting circuit that counts each time the output of the sequential pulse generator goes around. input to the selection control circuit to control the output signal waveform of the signal generation circuit over a cycle that is 2' times the cycle of the output of the /[order pulse generator. It is something to do.

(5) Embodiment of the Invention FIG. 1 is an explanatory diagram of the configuration of an embodiment of a sound source device for an electronic musical instrument according to the present invention. In the figure, 4 is a sound source device according to the present invention, and 5 is a key press detection/pronunciation assignment device that supplies necessary signals to the sound source device 7i4.

That is, the key press detection/pronunciation assignment device 3 includes a key press detection circuit 7 that detects keyboard ON/OFF information and pitch information from the keyboard 1 and sound source waveform selection information from the tone tablet 2; Clock signals CKI, CN3゜..., CKn (
3 is the clock generation circuit 8 that generates the number of sound generation channels)
, a sound generation assignment circuit 9 that allocates the clock generation circuit 8 to a sound generation channel according to the pressed key (w#t), and a keyboard 0N10pF information, sound source waveform selection information, escivelope information, etc. necessary for the sound source device 4 according to the pressed key information. and a data generation circuit 10 that generates a data signal, and a data signal from the data generation circuit 10 to the valley sounding channel CH1 of the sound source device 4.
,CH2* ”'tcfln Valley Latte 15-1115
-21"'+ 15-mH... controls the operation of the timing generation circuit 11 that generates the latte pulse TI I T2 +... and the circuits 7, 8, 9, 10.11 above. A control circuit 12 and a memory circuit 13 that stores programs for the control circuit 12, fixed data for generating data signals, data indicating the operating state, etc.
It consists of

The output signal from the key press detection and sound generation assignment device d6 is transmitted to a plurality of channels Cf (1, CH2, . . . ) having the same configuration.
. , CHn are supplied to the sound source device 4.

The operation of the plurality of channels of the sound source device 4 will be explained using the first channel CH1 as a representative. In the first channel CH1, the clock generation circuit 8 is assigned to CH1.
The clock signal CKI outputted from the sequential pulse generator 14 is supplied to the sequential pulse generator 14, while the sound source waveform selection information in the output signal of the data generation circuit 10 is supplied to the sequential pulse generator 14.
...-15-m, and timing generation circuit 1
2 pulses from 1 Tl m Tg j..., T,
1% doubles the percentage. selection control circuit 16-t,
16-s...

16-s, the output signal LP of the sequential pulse generator a14 is appropriately selected by the selection control signal output from the two sets 15-1.15-z, . . . , 15-, and the selection control circuit 16-516- g, ..., 16-m output signal S
Signal generating circuits 17-1, 17-s+, . . . , 17- which receive Pt+S P2#..., S Ps as inputs
Accordingly, sound source signals PK1#PK2#..., PK- are generated. Further, the data generation circuit 10 supplies the ratte 18 with a two-time pulse T from the timing generation circuit 11.
The envelope information such as the key fiONn'0FF1 signal and attack/decay/sustain/release generated by the envelope generating circuit 19 generates an envelope for amplitude modulating the sound source signals PKi, PKz, ..., PKs. The signal EV is supplied to envelope modulation circuits 20-1, 20-g, . . . , 20-m. Signal generation circuit 17-1.17-w, -, 1
7='m output signals PK1, PK2, "',
PKtn is envelope liquid 1 circuit 20-1.20-g,
..., analog amplitude modulation is performed by the envelope No. 1a EV in 20-s, and this output becomes the output signal P1aP2* of the first channel CH1 of the sound source device 4.
It becomes Pt+t.

Each channel Cf (1, CH2,...
, CHn each output PI r pHt...ps, pi
, p6 , +H・, P', , H+H, Pf
, pS.

..., P false is appropriately synthesized by resistors, and a tone circuit 5-1.5-g consisting of a filter circuit, an effect circuit, etc.
'H5-911, which controls the harmonic characteristics of the sound source waveform and converts it into a desired musical tone No. 1a. Tone circuit 5-
1.5-2. ....

The respective outputs of 5-1 are appropriately synthesized by resistors, converted into sound by a sound system 6 including an effect circuit and a speaker, and produced by a player of an electronic musical instrument.

FIG. 2 is a detailed explanatory diagram of the main parts of the embodiment of the present invention. That is, each channel CH1 of the sound source device 4 shown in FIG.
, CH2, . . . , CHn, a sequential pulse generator 14 provided in each of the plurality of waveform generation systems/columns, a latte 15-1, a selection control circuit 16-1, and a signal generation circuit 17-1. This shows the part.

In FIG. 2, the sequential pulse generator 14 includes a basic pulse train generation circuit 21 to which an input clock signal CK1 is supplied.
, a pulse conversion circuit 22 that converts the input clock signal CK1 into a short pulse-like clock CK', and an output signal of the basic pulse train generation circuit 21 and the pulse conversion circuit 22.
a sequential pulse shaping circuit 26 which receives the output signal of and generates a sequential pulse to be supplied to the selection control circuit 16-1.
It consists of An example of this operation will be explained using the waveform diagram shown in FIG. 6. In response to the input clock signal CK1, the basic pulse train generation circuit 21 sequentially generates a pulse train of α161cl... This can be easily constructed using circuits such as a ring counter, a shift register, a counter and a decoder. On the other hand, the pulse switching circuit 22 generates a clock OK' having a pulse width τ sufficiently smaller than the pulse width t of the input clock 1d CKI. This can be easily constructed using a circuit such as a delay circuit, a two-time constant circuit, a two-stage, two-stage circuit, or the like. The sequential pulse shaping circuit 23 inputs the output signal α161'l... of the basic pulse train generation circuit 21 and the output signal CK' of the pulse conversion circuit 22, and outputs α', b', C'.
, . . . generate pulse trains that do not overlap in time.

In FIG. 2, the selection control circuit 16-1
-Multiple AND/GO corresponding to each bit output of 1)
24a, 24b, 24c, . . . and an OR gate 25 which receives as inputs the output signals of these AND gates and an output signal directly and appropriately selected from the output of the sequential pulse generator 14. Here, each of the plurality of AND gates 24α, 246.24C, . It is something to do.

Further, although the signal generation circuit 17-1 uses a T-flip 70 tube 26 as a digital state transition device here, it is also possible to directly connect an analog binary function generation a. An example of this operation will be explained using the waveform diagram shown in FIG. 4. The output signals α1. of the sequential pulse generator 14.
b', C1, . . ., AND gates 24α, 24b, 24c, .
The pulses selected through the AND gates and the pulses directly selected in advance without going through the AND gates become the output signal of O1 by the OR gate 25. The T flip-flop 26 changes its state using the pulse of the input O1 as a changing point, and generates an output waveform 02. Here, latte 1
By changing the selection control signal of 5-1 by 1 bit, OR gate 2
The output pulse of 5 is 7'CO by removing one pulse from 〇5.
1', the output signal of the T flip-flop 26 becomes 02/, and it can be seen that the output signal waveform and duty ratio can be changed significantly with a change of 1 bit.

FIG. 5 is a waveform diagram showing another example of this operation. The pulse output selected by the selection control circuit 16-1 is
Os&, 03a, the output signal waveform of the corresponding signal generation circuit 17-1 is Os+04b, respectively.
With the same circuit configuration as shown in +046, it is possible to obtain a plurality of types of output waveforms having the same duty ratio and having an octave relationship with each other depending on the selected pulses. In general, in a sound source device for an electronic musical instrument, it is effective to synthesize multiple sound source waveforms that are in an octave relationship to each other when generating one musical tone. By being able to select the output waveform as appropriate, musically rich instrument sounds can be easily obtained.

FIG. 6 is a configuration explanatory diagram of another embodiment of the present invention. In this case, the sequential pulse generator 14 has, for example, four stages, and substantially the output waveform of the sound source device and the colleague using the sequential pulse generator of 16 stages is obtained. This is difficult to achieve with the conventional method in which the logical sum of the outputs of ring counters is used as a waveform output. In addition, not limited to 4 stages, in general, an n-stage sequential pulse generator is used, which is substantially 2" x 7L x 2" (n=l, 2.
. . , n=1, 2° . . .) It is possible to obtain an output waveform similar to that of a sound source device using a stage sequential pulse generator.

In FIG. 6, the output signal of the valley stage of the sequential pulse generator 14! +(J+h is sent to the AND gate 24α, 246.240 of the selection control circuit 16-1, and the output signal e is sent to the two-stage binary counter 28 and the selection control circuit 16-1.
1 or gate 25, respectively.

The counter 28 is counted by the output signal e of the sequential pulse generator 14 every time the output of the sequential pulse generator 14 goes around, and the output signal i is counted every time the output of the sequential pulse generator 14 goes around. The output logic state of the signal j changes every two cycles of the output of the sequential pulse generator 14. Five output signals of the ratte 27 providing selection control signals ps Q r ? '+8 +U is counter 28
The output signals are supplied to OR gates 29a, 29b and AND gates 24a, 24b, 24c, respectively. The output signal 05 of the OR gate 25 which receives the output signals of the AND gates 24α and 246° 24c and the output signal e of the sequential pulse generator 14 is an OR game) 2
The output signal 06 of the AND gate 61 is supplied to the AND gate 61 together with the output signals of the AND gates 9a and 29b.

On the other hand, the output signal of the AND gate 60 which receives the two output signals Ztj of the counter 28 and the output signal 5 of the sequential pulse generator 14 is supplied as a clear input of the flip-flop 26. The output clears 7 rips and 26 flops in each final stage after 4 rounds.

In the configuration shown in FIG. 6 above, the operation of this implementation tzt+ will be explained using the waveform diagram shown in FIG. 7.
The output signal of the sequential pulse generator 14 supplied with I is 'J
+(1+h), and the output signal of the counter 28 is Z+j.Here, for example, the selection control signal of the ratte 27 is r="kl", s="L".

When U="H", the output signal of the OR gate 25 is 05
become that way. The selection control signals p and q of the latch 27 are applied to the AND gate 61 for the four possible combinations of the color q for 1i4@Os.
1 output signal 06 is Osa r Oa & , Osc
, 06d, the output signal 07 of the flip-flop 26 operating with this input signal 06 as a changing point becomes 07αs 07b +07a g Otd.

In this way, the selection control signals r, 8. 'll
Rather than being able to selectively control the output waveform as appropriate by r, the period of the output waveform can be controlled by adjusting the output of the sequential pulse generator 14 to 1.
It is possible to selectively control the waveform for four times the cycle period, and if the number of stages of the counter 28 is set to four, generally 27@
It can be expanded to In addition, by clearing the flip-flop 26 by the output signal of the ANDGOO) 50, the output of the sequential pulse generator 14 is output four times (generally 2n times )
The same repeated waveform output is obtained in the period of .

(6) Effects of the Invention As described above, the present invention enables a wide variety of types to be generated with a simple configuration by appropriately selecting and controlling only the pulses corresponding to the changing points of the waveform output from among the output pulses of the sequential pulse generator. It is possible to obtain an effective waveform output, and to be able to select a wide variety of waveform outputs with rich arbitrariness using the same circuit configuration.
In electronic musical instruments,
This is very effective for generating performance sounds with rich musicality.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of the configuration of an embodiment of the sound source device of an electronic musical instrument according to the present invention, FIG. 2 is a detailed explanatory diagram of main parts of the embodiment of FIG. 1, and FIGS. A waveform diagram showing the operation of the embodiment, FIG. 5 is a waveform diagram showing another operation of the embodiment of FIG.
FIG. 6 is an explanatory diagram of the configuration of another embodiment of the present invention, and FIG.
This is a waveform diagram showing the operation of the embodiment shown in the figure.
2 is a tablet, 3 is a key press detection/pronunciation assignment device, 4 is a sound source device, 5-1""3- is a tone circuit, 6 is a sound system, 7 is a push-pull calculation circuit, 8 is a clock generation circuit, 9
10 is a data generation circuit; 11 is a timing generation circuit; 12 is a control circuit; 16 is a storage circuit;
is a sequential pulse generator, 15-1 to 15-m, 18°2
7 is a latch circuit, 16-1 to 16- are selection control circuits,
17-1 to 17-1 are signal generation circuits, 19 is an envelope generation circuit, and 20-1 to 20-m are envelope change tA.
! l! l path, 21 is a basic pulse train generation circuit, 22 is a pulse conversion circuit, 23 is a sequential pulse shaping circuit, 24α+24
b, 24c+60+61 is an and gate, 25.29α
, 29b is an or gate, 26 is a flip-flop, 28
indicates a counter. Patent applicant Kawai Musical Instruments Co., Ltd. Representative Patent attorney 1) Yoshishige Saka + a + @ - country 2, -1, chain and 0

Claims (4)

[Claims] (1) A sequential pulse generator that generates sequential pulses by inputting a clock signal corresponding to a musical tone frequency, and a sequential pulse generator that corresponds to a change point of a sound source signal output waveform by inputting an output signal of the sequential pulse generator and a selection control signal. The device includes a selection control circuit that selects a pulse, and a signal generation circuit that receives an output signal from the selection control circuit as input and whose state changes to generate a sound source signal, so that the output signal waveform of the signal generation circuit can be controlled. A sound source device for an electronic musical instrument, characterized by the following. (2) a sequential pulse generator that generates sequential pulses by inputting a clock signal corresponding to a musical tone frequency; 1; a counting circuit that counts each time the output of the sequential pulse generator goes around; and an output of the sequential pulse generator. a selection control circuit that receives the signal, the output signal of the counting circuit, and the selection control signal as inputs and selects a pulse corresponding to a changing point of the sound source signal output waveform; It is characterized by comprising a signal generation circuit that generates a signal, and capable of controlling the output signal waveform of the signal generation circuit over a cycle that is 2' times the cycle of the output of the sequential pulse generator. Sound source device for electronic musical instruments. (3) The signal generation circuit is cleared and initialized every time the output of the sequential pulse generator goes around. Sound source device for electronic musical instruments. (4) 2 of the period in which the output of the sequential pulse generator goes around;
3. The sound source device for an electronic musical instrument according to claim 2, wherein the 1d number generation circuit is cleared and initialized at every cycle times 1.