JPS602996A - Musical sound generator - 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 The present invention relates to a musical tone generator (JIL), particularly one using a waveform memory read method.

This type of waveform readout type musical tone generation device is used in electronic musical instruments, autorhythm performance devices, etc., but conventionally, waveform data for one period of a desired musical sound waveform is stored in a waveform memory in advance. The waveform data stored in the waveform memory is read out at a predetermined speed corresponding to the number of dove waves of the musical tone to be generated (that is, at a speed corresponding to the height assigned to the pressed key). ing. in this case,
The waveform of the musical tone signal is simply the one-cycle waveform stored in the waveform memory as the basic waveform from the start of sound generation (i.e., the rise of the sound) to the end of the sound generation (i.e., the fall of the sound). It was not possible to change the waveform of musical tone No. 48 over time, just by changing the level.

However, in general, the waveform of musical tones generated when a natural musical instrument is played changes rapidly from the time the musical tones begin until they end. The musical tones lacked a sense of naturalness, and it was inevitable that the performance expression would be monotonous.

In order to solve this problem, we created a drum shape (waveform approximating that of a natural instrument) between the start and end of musical tones.
It is conceivable to store the entire waveform memory in the waveform memory, but
If this is done, there is a problem that the storage capacity of the waveform memory becomes enormous.

This invention was made in consideration of the above points, and aims to generate musical tones as rich in naturalness as possible using a waveform memory with as small a storage capacity as possible. In the invention, the data of the reference waveform that is repeatedly included in the string sound drum shape of the song in 1 from the start to the end of the musical tone? At the same time, the data of the differential waveform representing the difference between the musical tone waveform and the early shaping is stored in the differential waveform memory, and the waveform data of the reference waveform memory is read back and used as the waveform of the differential waveform memory. Musical sounds can be created by synthesizing data.
to form.

An embodiment in which the present invention is applied to a chestnut maker will be described below in detail with reference to the drawings.In FIG. Samples of the reference waveform W1 (Fig. 3) in which the percussive sound waveform Δ・1 of a piano, guitar, etc. is repeatedly distorted from the time it starts sounding at time t1 until it ends at time t2. Point waveform data is stored with a series of addresses attached for a predetermined cycle, for example, one cycle.

Further, 2 is a differential waveform memory that stores waveform data of the differential waveform, which stores waveform data of each sample point of the musical sound waveform M from time t1 to time t2 in FIG. 2, and from time t□ to time t2. Difference waveform data between each sample point waveform data of the reference waveform W1 when the quantity reference waveform W1 is returned is stored by requesting a series of addresses. Here, the addresses for the differential waveform data are divided into a number of consecutive blocks, each block having a length corresponding to the length of one period of the address for the reference waveform data. Second. Third... A structure is employed in which, for example, the upper bits have a block address portion representing a block, and the lower bits have the same address portion as a series of addresses for reference waveform data.

Thus, the first . 2nd゜3rd
. . . Each time the address part corresponding to a block is specified, the first... 2nd゜3rd...
- The differential waveform data included in the block can be read out in synchronization with the repeated reading of the reference waveform data in the reference waveform memory 1.

In FIG. 1, reference numeral 3 denotes a pitch-corresponding numerical data memory, which receives pressed key number data S1 representing the key number of the pressed key from the key [4] as an address signal. For example, if the pitch becomes the capital, the numerical data that increases accordingly is given to the F'c-acculator 5 as cumulative data. The accumulator 5 is given a key-on pulse KON P, which is generated each time a new key is pressed on the keyboard 4, as a clear signal; Numerical data F, which is cleared and whose size corresponds to the pitch of the key, is repeatedly accumulated at a predetermined period. Thus, the accumulator 5 becomes 1.1.3.
Each time the cumulative output qF is repeated n times, the cumulative output qF rises in steps like 1F, 2F', 3F, etc., and this r is stored in the reference waveform memory 1 and It is applied to the differential waveform memory 2 as a sample point address signal AD1.

When the accumulated content of the accumulator 5 reaches the maximum value (for example, all bits are all "1"), the carry signal C
ARY is sent and a new accumulation operation is performed again, and as the numerical data F becomes larger (in other words, if the pitch of the operated key is higher), the cycle becomes shorter accordingly. By reading out the waveform data stored in the memories 1 and 2, reference waveform data W□ and differential waveform data DF of the pitch corresponding to the operated key are sent out.

The carry signal CALα of the accumulator 5 is given to the block counter 6, and the key-on pulse K
Counting starts from the state cleared by ONI', and the count output S4 is given to the differential waveform memory 2 as block address signal 6.

The block counter 60 count output S4 is given to the maximum block detection circuit 7. The maximum block detection circuit 7 is
The count output S4 is the number Zy of the largest block among the blocks of the differential waveform memo IJ2! When the value exceeds ', this is detected and an operation prohibition signal 85 is applied to the accumulator 5 to prevent the accumulator 5 from carrying out any further accumulation operation.

In this way, the reference waveform data W□ and the difference waveform data DF escaped from the reference waveform memory 1 and the difference waveform memory 2 after the accumulator 5 starts the accumulation operation and until it stops the accumulation operation are stored in the adder circuit. They are synthesized in a synthesizing circuit 8, and the synthesized output is given to a sound system 9 as each musical tone W2 and converted into a musical tone.

In the above configuration, when a key is pressed on the keyboard 4 at time t□ in FIG. 2, the accumulator 5 and block counter 6 are cleared by the key-on pulse K (JNP), and The accumulator 5 receives the numerical data F by reading out the numerical data F of the corresponding pitch from the pitch-corresponding number 1 direct data memory 3.
The address of the reference waveform memory 1 is accessed at a rate corresponding to the size of . Thus, when the accumulation operation is repeated until the maximum value is reached (5 accumulators), the result is shown in Figure 4 (2).
One cycle of reference waveform data W as shown by the broken line in
1 is read out at a frequency corresponding to the pitch of the pressed key. At the same time, the first block is added to the differential waveform memo 1 and 2 by the block counter 60 count output S4, and each address in the first block is specified by the cumulative output qli''K of the accumulator 5, Thus, the differential waveform data Dli'1 of the first block as shown in FIG. 4) is escaped from the differential waveform memory 2.

In this way, the synthesis circuit 8 adds V[the output reference waveform data W□ and the differential waveform data DFIY to obtain
), a musical tone signal W2 as shown by reference numeral W21 is sent to the Y sound system 9.

Eventually, when the accumulator 5 exceeds the maximum value, the block counter 6 starts counting to 1 by the carry signal CARY from the accumulator 5, and the count output S4 of each block specifies the second block and the block counter 6
repeats the operation, visits and outputs the memories 1 and 2, and sends out the musical tone signal W2 to the sound system 9 in the same manner as in the above case.

Thereafter, each time the block counter 6 performs a counting operation, each address of the reference waveform memory 1 is read out, and each address included in the added block of the differential waveform memory 2 is read out. t. For the n-th block corresponding to
By adding the differential waveform data 1) Fn to the abstract waveform data W1, a musical tone signal W2 having a waveform W2n (Fig. 5 (8)) different from that of the first block is obtained.

Eventually, at time t2 in FIG. 2, the block counter 60 count output S4 exceeds the initial value and the differential waveform memo! Since the reading of the data stored in 72K is completed, the operation of the accumulator 5 is disabled and the sound generation operation is stopped.

As described above, with the configuration shown in FIG. 1, it is possible to obtain a musical tone generating device that can change the waveform as necessary from the start of sound generation to the end of sound generation. In doing so,
A comparatively large amplitude part of the waveform of each period of the musical tone signal W2 is assigned to the reference waveform W0, and a change in the waveform is assigned to a comparatively small amplitude differential waveform DF...DF'.・・・
・Waveform memo IJ
The total storage capacity of 1 and 2 can be significantly reduced compared to the case where all the waveform data of the musical tone signal W2 is stored.

By the way, the reference waveform W1 of the large amplitude part is the reference waveform memory 1.
By reading out the data repeatedly, the memory capacity can be made sufficiently small.

Here, especially for the whole block, the difference waveform DF1...
・If the waveform of the reference waveform W□ is selected so that the amplitude of DFn... is as small as possible, the overall [memory capacity t
can be made even smaller.

FIG. 6 shows another embodiment, in which the pitch-corresponding numerical memory 3 shown in FIG.
and shows a part to replace the accumulator 5. In FIG. 6, the pressed key number signal 81 sent from the nail board 4 is received by the note clock generation circuit 15, and a clock pulse sii of a frequency corresponding to the pitch of the pressed key is generated.
'v is generated and counter 1 is generated at this clock pulse Sll'.
6 as a count input.

The counter 16 receives the key-on pulse KONP' as a clear signal and starts the counter from an all "0" state, and also receives the detection signal 85 of the maximum block detection circuit 7.
Received as a Y operation prohibition signal. As a result, key on 41
The temporary count output 5i21ft in which the i-th KONP is generated and the counter 16 is cleared is sent to the reference waveform memory 1 and the differential waveform memory 2 as an address signal AI)1. Therefore, the counter 16 counts the contents (
Therefore, the same operation and effect as in the case of FIG. 1 can be obtained.

In the above description, a case has been described in which one period's worth of waveform data is stored in the reference waveform memory 1, but instead of this, the same effect as in the above case can be obtained even if multiple periods' worth of waveform data are stored. be able to.

As described above, according to the present invention, there is a reference waveform memory that is repeatedly read out, and a differential waveform memory that is read out sequentially from the time when musical tones are generated. With this arrangement, musical tones with a rich natural feel similar to those produced by natural musical instruments can be generated using a waveform memory with a significantly smaller storage capacity.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a musical tone generator according to the present invention, FIG. 2 is a signal waveform diagram showing generated gantry signals, FIG. 3 is a signal waveform diagram showing reference waveforms, and FIGS. FIG. 5 is a signal waveform diagram showing waveforms at times t1 and tn in FIG. 2, and FIG. 6 is a block diagram showing another embodiment of the present invention. ]...-Single waveform memory, 2...Differential waveform memory, 3
...Pitch-corresponding numerical data memory, 4...Keyboard, 5.
...Accumulator, 6...Block counter, 7.
... Maximum block detection circuit, 8... Synthesis circuit, 15.
- Note clock generation circuit, 16... counter. Figure 3 Figure 5 Figure n 4th factor 1': $ 6 Figure

Claims (1)

[Scope of Claims] a. A reference waveform memory that stores reference waveform data that is repeatedly read out while a musical tone is being generated; b. The above-mentioned reference waveform data corresponding to each sample time while generating a musical tone. and a differential waveform memory that stores differential waveform data representing the difference between the tone signal and the musical tone signal to be generated. C0 A musical tone generating device comprising: a musical tone synthesis circuit that synthesizes waveform data respectively read from the reference waveform memory and the differential waveform memory to form a musical tone signal.