JPH05341790A - Sound source device - Google Patents

Abstract

PURPOSE:To form musical sounds without monotonous using very small amount of data by storing loop waveform data and pitch variation and repeatedly reading the loop waveform data with the frequency modified by the pitch variation. CONSTITUTION:External sound is sampled by a microphone 20. By this sampling, musical sound waveform signals are stored in a sampling memory 19. In order to edit, the envelop of musical sound waveform signals, which are sampled, is displayed on a display 15. A player divides the entire waveforms of the musical sound into plural states by operating a panel switch 16. For each divided state, the the player designates either to store the entire waveform data or to store only one period of the waveforms as the loop waveform data and to loop it. And the stored data are successively read for every one period by a reading circuit 18 and the waveforms are displayed on the display 15. By selecting an appropriate one period from the displayed waveforms, a segmenting is performed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tone generator which saves memory capacity by repeatedly reading loop waveforms.

[0002]

2. Description of the Related Art A sampling sound source has been put into practical use as a sound source device for realistically reproducing the musical sound of a natural musical instrument. The basic function of the sampling sound source is to store the tone waveform of a natural musical instrument from sounding to muffling, and read this data from the beginning at a specified frequency. However, in such a system, it is necessary to store the musical tone waveform data of the length from the pronunciation to the muffling for one musical tone, which requires a huge memory capacity. In addition, the above system cannot be applied to the continuous tone as long as it is necessary to continuously form a tone signal as long as the pronunciation is instructed.

Therefore, only a short (1 to several cycles) loop waveform data is stored in the sustaining portion of the musical tone waveform with little fluctuation, and the looped waveform data is repeatedly read out to obtain a musical sound of any length (sustaining portion). ) Has been put to practical use in a loop-type sampling sound source.

[0004]

However, there is a drawback that the tone becomes monotonous because the loop waveform data must be repeatedly read many times in order to produce a long tone. On the other hand, if the loop waveform data is lengthened to eliminate monotonousness, the memory capacity required for one musical tone becomes large, and the effect of looping the sustaining portion is lost.

An object of the present invention is to provide a sound source device capable of eliminating monotonousness by storing only frequency fluctuations in a loop section (steady part) without forming a loop.

[0006]

The invention according to claim 1 of the present application is a sound source device for forming a stationary musical tone signal by repeatedly reading loop waveform data, which is a waveform storage for storing loop waveform data. Means, pitch variation storage means for storing a pitch variation that changes with the passage of time, and correction means for correcting the frequency of a musical tone over time with the pitch variation stored in the pitch variation storage means when the frequency is specified. And reading means for repeatedly reading the waveform storage means at a corrected frequency.

The invention of claim 2 of this application is a means for storing all waveform data, a waveform storage means for extracting and storing specific one or several cycles of loop waveform data from this all waveform data, and this loop. Pitch variation storage means for extracting and storing pitch variation of all waveform data with respect to the waveform data.

[0008]

According to the first aspect of the invention, the sound source device forms a tone signal by repeatedly reading the loop waveform data stored in the waveform storage means. This reading is performed at the frequency of the musical sound instructed to be sounded. At this time, this frequency is corrected over time based on the pitch fluctuation stored in the pitch fluctuation storage means (correction means), and the corrected frequency is corrected. To access the waveform storage means (reading means). Pitch variations are stored over the entire loop interval and the read frequency is modified over time (as the loop interval progresses), thus eliminating repetitive monotonicity.

In the sound source device according to the second aspect, the waveform data of one or several cycles is extracted as the loop waveform data from all the waveform data, and only this waveform data is stored in the waveform storage means.

Further, the pitch fluctuation of all the waveform data for this loop waveform data is extracted and stored in the pitch fluctuation storage means. The pitch fluctuation may be stored, for example, as a ratio or a difference between the frequency at each point of the waveform data and the frequency of the loop waveform data.

[0011]

1 is a block diagram of an electronic musical instrument having a sound source device according to an embodiment of the present invention. This electronic musical instrument is an electronic keyboard musical instrument having a keyboard 14 for playing. Further, the sampling circuit 17 is provided so that the tone waveform which is the basis of the tone signal to be formed can be sampled and stored.

The operation of this electronic musical instrument is controlled by the CPU 10. ROM1 to CPU10 via bus 11
2, RAM 13, keyboard 14, display unit 15, panel switch 16, sampling circuit 17, reading circuit 18,
The sound source 21 and the writing circuit 22 are connected. R
The OM 12 stores a control program for controlling the operation of this electronic musical instrument. A register for temporarily storing various data generated during performance or sampling is set in the RAM 13. The panel switch 16 is provided with a switch for selecting a tone color and various operators for editing a musical tone waveform sampled at the time of sampling. A microphone 20, a reading circuit 18, and a sampling memory 19 are connected to the sampling circuit 17. An analog musical tone signal of a natural musical instrument is input from the microphone 20. The sampling circuit 17 digitizes the analog musical tone signal input from the microphone 20 and sequentially stores it in the sampling memory 19. Readout circuit 18
When editing the sampled musical tone waveform data, the sampling memory 1
The tone waveform signal stored in memory 9 is read out to RAM1.
Transfer to 3. The sound source 21 has a structure as shown in FIG. 2, and is connected with a waveform memory 23, a frequency ratio memory 24 and a writing circuit 22. When the sound source 21 forms a tone signal, the waveform memory 23 is accessed at the frequency designated by the CPU 10 in the normal section to read the waveform data. In the case of the loop section, the frequency designated by the CPU 10 is corrected by the data of the frequency ratio memory 24, and the waveform memory 23 is accessed to repeatedly read the loop waveform data. The writing circuit 22 is a circuit for writing the musical tone waveform data and the frequency ratio read from the sampling memory 19 into the waveform memory 23 and the frequency ratio memory 24.
Here, the frequency ratio is the frequency ratio of the waveform data of the other part to the loop waveform data in the loop section.
The tone signal generated by the sound source 21 is output to the sound system 25, amplified, and then output to the outside.

Now, the sampling system of the electronic musical instrument will be described with reference to the flow chart of FIG. 3 and the various signal waveforms of FIGS. First microphone 20
Is used to sample an external sound (a musical sound of a natural musical instrument) (n1). By this sampling, Fig.4 (A), (B)
A tone waveform signal (original sound) as shown in FIG. Here, FIG. 4 (A) shows the envelope of the original sound, and FIG. 4 (B) shows the pitch fluctuation.
For editing, the envelope of the sampled tone waveform signal is displayed on the display unit 15. The player operates the panel switch 16 or the like to divide the entire waveform of the musical sound into a plurality of states (see vertical broken lines in FIGS. 4 and 5).
The division may be performed, for example, at the boundary of the characteristics of the tone signal such as the attack / decay portion, the sustain portion, and the attenuation portion. 4 and 5
The tone signal is divided into five states (ST = 1 to 5). For each divided state, specify whether to store all waveform data or only one cycle waveform as loop waveform data and loop it (n
2). In the case of the tone waveforms of FIGS. 4 and 5, all waveform data are stored in the states ST = 1, 3, 5 (all waveform states), and only loop waveform data are stored in the states ST = 2, 4 (loop State). The waveform of one cycle is cut out from the loop state and this amplitude is normalized (n
3). The loop state waveform data is sequentially read by the reading circuit 18 every one cycle, and the waveform is displayed on the display unit 15. The cutting is performed by the user selecting an appropriate one cycle from the displayed waveform. Figure 4
80 and 81 in (A) represent one selected cycle. After that, the waveform data is written in the waveform memory 23 (n4). The waveform data of all waveform states is transferred to the waveform memory 23 via the read circuit 18 and the write circuit 22, and the waveform data of the loop state (loop waveform data) is processed by the RAM 13 and then passed through the write circuit 22. Are transferred to the waveform memory 23. Each waveform data is stored in a predetermined address in order of state (see FIG. 5 (A)). Further, the frequency ratio data is written in the frequency ratio memory 24 (n5). This data is stored only for loop states. The frequency ratio between the cut-out loop waveform data and the waveform data of other portions is calculated for each cycle and written in the frequency ratio memory 24. The frequency ratio is calculated by comparing the lengths of one cycle, and the frequency ratio data at the cutout points 80 and 81 of the one cycle waveform is 1. The calculated frequency ratio data is shown in FIG.
It becomes the data like 60 and 61.

FIG. 2 is a block diagram of the sound source 21.
To the sound source 21 via the bus 11, a note-on signal NON,
A note number (data indicating frequency) and a tone color number are input. In addition, the tone color data register 30 stores tone color data of a plurality of tone colors in advance. The tone color data of the inputted tone color number is inputted to the data supply circuit 31. The data supply circuit 31 is a circuit for outputting various data input from the tone color data register to each circuit at a necessary timing.

On the other hand, the waveform memory start address SA, the waveform memory end address EA and the loop signal LP are inputted from the data supply circuit 31 to the address counter 35 which accesses the waveform memory 23. LP is 1 in the loop state and 0 in the full waveform state (FIG. 4 (D)). In addition, a note-on signal N is sent via the bus.
ON is input. Further, an F number, which is data indicating the frequency of a musical tone, is input from the multiplier 41 to the address counter 35. The F number is converted by the F number conversion circuit 32 based on the note number input from the CPU 10. The converted F number is modified by the frequency ratio data in the multiplier 41. The multiplier input to the multiplier 41 is obtained by interpolating the data in the frequency ratio memory 24 in the loop state, and is 1 in the entire waveform state. That is, the F number is not modified in all waveform states. The address counter 35 starts to output the address AD triggered by the input of the note-on signal NON (FIG. 5 (A)). The address AD is output from the waveform memory start address SA in increments based on the F number, and ends when the waveform memory end address EA is reached. However, in the case of a loop, SA is output again after outputting EA (see (70), (71) in FIG. 5A and FIG. 6).
Is a partially enlarged view of (70). ). This is repeated a predetermined number of times, and the loop end detection signal LE is output for each repetition. The number of LEs is counted by the loop counter.
The count value LN of the loop counter 37 is input to the comparator 36 together with the loop count data LT output from the data supply circuit 31. The comparator 36 outputs the loop state end signal OV when LN exceeds the loop count data LT (FIG. 5 (B)). On the other hand, when EA is output in all waveform states, the address counter 35 causes the state end signal EN.
D is output (FIG. 5 (B)). Both END and OV are input to the state counter 33. The state counter 33 is a counter that is reset by the note-on signal NON (1 is preset) and is counted up by the input of END or OV. The count value is input to the data supply circuit 31 as state data ST (see FIG. 4C). The data supply circuit 31 outputs various data according to the input state ST.

The LN is also input to the adder 38.
The frequency ratio memory start address PSA is supplied from the data supply circuit 31 to the adder 38. PSA and L
The added value of N is used as an access address in the frequency ratio memory 2
4 is supplied. Therefore, new frequency ratio data is read for each loop in the loop state (see (60) and (61) in FIG. 5C). The read frequency ratio data is interpolated by the interpolation circuit 39 and then input to the adder 41 via the selector 40.

The interpolation circuit 39 performs a cross-fade process so that the frequency ratio data of the previous time is smoothly shifted to the frequency ratio data of this time. The loop signal LP is input to the selector 40. LP is 1 (loop state)
In the case of, the frequency ratio data input from the interpolation circuit 39 is output to the multiplier 41, and when LP is 0 (all waveform states), 1 is output to the multiplier 41.

Waveform data is output from the waveform memory 23 accessed by the address AD. This waveform data is input to the multiplier 42. The envelope signal is input to the multiplier 42 from the envelope generator 34. The digital tone waveform with the envelope added by the multiplier 42 is input to the D / A converter 43 and converted into an analog tone signal. This tone signal is input to the sound system 25. The envelope generator 34 is reset by the note-on signal NON, and the parameters for generating the envelope are input from the data supply circuit 31.

Thus, in the loop state, the frequency of the waveform data is corrected in each cycle even in one cycle, and the monotony of the repetition can be eliminated.

In this embodiment, one cycle of waveform data is used as the loop waveform data, but a plurality of cycles of waveform may be used. Further, the frequency ratio data is also calculated and stored for each cycle, but the frequency ratio data may be calculated for each cycle.

[0021]

As described above, according to the present invention, the loop waveform data and the pitch fluctuation are stored, and the loop waveform data is repeatedly read at the frequency corrected by the pitch fluctuation. With, it is possible to form a tone signal having no monotonicity.

[Brief description of drawings]

FIG. 1 is a diagram showing a configuration of an electronic musical instrument to which the present invention is applied.

FIG. 2 is a diagram showing a configuration of a sound source of the electronic musical instrument.

FIG. 3 is a diagram showing an operation procedure when sampling a musical sound of a natural musical instrument in the electronic musical instrument.

FIG. 4 is a diagram for explaining a change state of various signals in the electronic musical instrument.

FIG. 5 is a diagram for explaining a change state of various signals in the electronic musical instrument.

FIG. 6 is a diagram for explaining a change state of various signals in the electronic musical instrument.

[Explanation of symbols]

 17-sampling circuit 21-sound source 23-waveform memory 24-frequency memory

Claims (2)

[Claims] 1. A sound source device for forming a stationary tone signal by repeatedly reading loop waveform data, comprising a waveform storage means for storing the loop waveform data and a pitch for storing a pitch variation that changes with time. Fluctuation storage means, correction means for correcting the frequency of a musical tone over time with the pitch fluctuation stored in the pitch fluctuation storage means, and repeating the waveform storage means with the corrected frequency A sound source device comprising: a reading unit for reading. 2. Means for storing all waveform data, waveform storage means for extracting and storing specific one or several cycles of loop waveform data from this all waveform data, and pitch of all waveform data for this loop waveform data. A pitch tone storage means for extracting and storing a variation, and a sound source device.