JPH086566A - Electronic musical instrument - Google Patents

Abstract

PURPOSE:To provide an electronic musical instrument capable of obtaining easily the timewise change of the timbre of a musical sound generated by a sinusoidal synthesis without providing an envelope calculating circuit, etc. CONSTITUTION:In an electronic musical instrument synthesizing a musical sound based on higher harmonic coefficient set information being different at every timbre, this device is provided with a higher harmonic coefficient set storage memory 21 storing plural higher harmonic coefficient sets corresponding to at least one part of musical sound waveform ranging from the start of the sounding of one musical sound signal to the completion of the sound signal, a readout address generating means 20 reading out one of the higher harmonic coefficient set information repeatingly prescribed times and thereafter moving to the readings of next higher harmonic set information and musical sound signal generating means 25 to 30 generating a musical sound signal based on higher harminic coefficient set information read out by the readout address generating means 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic musical instrument, and more particularly to control of harmonic coefficients in a musical tone generating apparatus adopting a sine synthesizing method.

[0002]

2. Description of the Related Art Some conventional electronic musical instruments generate a plurality of harmonics of a tone of a certain tone by a sine synthesizing method and synthesize them to obtain a tone signal of a desired tone. It was In this sine synthesis method, in order to synthesize a tone waveform whose tone color changes with time, each harmonic coefficient of the reference harmonic coefficient set is modulated with an envelope that changes with time, or There has been a method of correcting with a formant filter that changes with time.

[0003]

In the conventional electronic musical instrument of the sine synthesizing method as described above, one musical tone is generated by dividing the reference harmonic coefficient and the element for temporally modulating it. The amount of data needed to
Compared with PCM (waveform memory) sound source, it is much less,
For example, there is a problem in that it is necessary to provide an envelope arithmetic circuit or the like for controlling each harmonic coefficient. The object of the present invention is to improve the problems of the prior art as described above,
An object of the present invention is to provide an electronic musical instrument which can easily obtain a temporal change in the tone color of a tone signal generated by sine synthesis without providing an envelope calculation circuit or the like.

[0004]

According to the present invention, in an electronic musical instrument for synthesizing a musical tone signal based on different harmonic coefficient set information for each timbre, at least a musical tone waveform from the start to the end of the generation of one musical tone signal. Harmonic coefficient set storage means for storing a plurality of harmonic coefficient sets corresponding to a part, and read address for shifting to the reading of the next harmonic coefficient set information after repeatedly reading one harmonic coefficient set information a predetermined number of times The present invention is characterized by comprising a generating means and a musical tone signal generating means for generating a musical tone signal based on the harmonic coefficient set information read by the read address generating means.

[0005]

According to the present invention, the musical tone signal is generated by switching the harmonic coefficient at every predetermined time by the means as described above. Therefore, any temporal change of the arbitrary harmonic coefficient can be easily obtained. . In addition, since the same harmonic coefficient set is repeatedly read at a portion where the same harmonic coefficient continues, an increase in the data amount of the harmonic coefficient set is suppressed. Furthermore, if a jump function is added and a specific harmonic coefficient group is repeatedly read out, it is possible to generate a continuous tone with a small amount of data. It is also possible to apply the present invention to the formant coefficient instead of the harmonic coefficient.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 2 is a block diagram showing the configuration of an electronic musical instrument to which the present invention is applied. The CPU 1 is a central processing unit that controls the entire electronic musical instrument, such as scanning keys and switches, assigning keys, and controlling pronunciation based on a program stored in the ROM 2. The ROM 2 stores control programs, tone color parameters, and the like. RAM3
Is used as a work area, and an area for storing tone color parameters set from the panel, various control tables, a MIDI buffer area, etc. are provided. Also,
It is battery backed up and is configured to retain the set information even when the main power is turned off.

The panel section 4 has a display device for displaying characters and figures by means of various selection switches for tone color, volume, liquid crystal, LED and the like. The keyboard unit 5 includes, for example, a keyboard including a plurality of keys each having two switches, and a circuit for scanning the state of each switch. The tone generation section 6, which will be described in detail later, is a sine synthesis type tone generation circuit that generates and synthesizes desired tone signals independently of a plurality of channels. The D / A converter 7 D / A converts the digital musical tone signal. The analog signal processing unit 8 is composed of a filter circuit for removing noise. The amplifier 9 amplifies the musical tone signal to drive the speaker 10. The bus 11 connects each circuit in the electronic musical instrument. In addition to this, a MIDI interface circuit, a floppy disk interface circuit, a memory card interface circuit, or the like may be provided if necessary.

FIG. 1 is a block diagram showing the configuration of the musical sound generating unit 6 according to the present invention. The selected address generator 20
Although details will be described later, key information (key on / off information, tone range, touch information, etc.), tone color information (tone color selection) and a clock signal (X) are input, and the harmonic coefficient set read address is input to the harmonic coefficient calculation unit 21. And supply data for interpolation calculation. The harmonic coefficient calculation unit 21, which will be described in detail later, has a built-in harmonic coefficient set memory and reads out two harmonic coefficients for each harmonic order based on the address supplied from the selection address generation unit 20. The interpolation calculation is performed and the harmonic coefficient Hq is output. The harmonic memory 22 is A,
B is a buffer memory capable of storing a harmonic coefficient set in each of the two areas. For example, while the harmonic coefficient calculating unit 21 is writing output data in the A area, the harmonic previously written in the waveform calculating unit 25 from the B area. The wave coefficient set is read. The selector 23 is for switching the write address Wq and the read address Rq output from the execution control circuit 24.

The execution control circuit 24 is a circuit for controlling the operation of the musical sound generating section 6, includes a counter circuit for counting clocks, and generates various timing signals and address signals. Although the details will be described later, the waveform calculation unit 25 receives the harmonic coefficient set Hq read from the harmonic memory 22 and the phase information P output from the execution control circuit in the same cycle as the harmonic coefficient calculation unit 21. Input and sequentially output musical tone waveform data for one cycle (for example, 256 sample values). The waveform memory 26 has two areas A and B, and each area has a waveform storage area for 32 channels, for example. Then, for example, while the waveform calculator 25 is writing the waveform data in the area A, the previously written waveform data is read from the area B under the control of the read address generation circuit 28.

The read address generating circuit 28, the envelope generator 29, and the multiplier 30 have the same functions as those used in the tone generating circuit of the PCM (waveform memory) system. The read address RA of the waveform memory is generated at address intervals corresponding to the key number (frequency) to be used. Selector 2
Reference numeral 7 is for switching the write address WA and the read address RA of the waveform memory 26. The envelope generator 29 generates envelope signals having different shapes depending on the tone color, tone range, and touch information. The multiplier 30 multiplies the waveform data and the envelope data. In addition,
The tone generation section of FIG. 1 performs a time division multiplexing operation, and simultaneously generates, for example, 32 channels of tone signals. Also,
Although not shown in the figure, after the multiplier 30, an addition / synthesis circuit for a tone signal of each channel, a sound image effect circuit, an effect addition circuit for reverberation or the like is provided.

FIG. 3 is a block diagram showing the configuration of the waveform calculator 25 of FIG. The read address generator 40 outputs phase information corresponding to each harmonic order by accumulating current value information P of the phase of the fundamental wave input from the execution control circuit 24. The sine function table 41 is a memory that stores sine waveform amplitude data for one cycle (for example, 256 sample values).
Using the phase information corresponding to each harmonic order output from the address as an address, the amplitude value of the sine waveform corresponding to the phase is read. The multiplier 42 multiplies the amplitude value read from the sine function table 41 and the corresponding harmonic coefficient Hq. The amplitude accumulator 43 sequentially outputs amplitude value data of musical tone waveforms by accumulating amplitude values corresponding to the first harmonic, that is, the fundamental wave to the 32nd harmonic.

FIG. 4 is a block diagram showing the configurations of the selected address generator 20 and the harmonic coefficient calculator 21. P
EG50 is a circuit that generates a pulse when the input signal rises, that is, when the key is turned on, and the pulse clears the counter H56. The EG 51 generates pulses when the input signal rises and falls, that is, at key-on and key-off. With this pulse, the counter L55
Is cleared and the flip-flop (FF) 52 is set. When the FF 52 is set, its output Q becomes 1 and is supplied to one input of the AND gates 53 and 60. Therefore, the AND gate 53 outputs the clock X to the counter L5.
5 is output.

On the other hand, the counter H56 is cleared when the key is turned on. The output of the counter H56 is the sequence memory 5
It is input to the lower address of 7. Further, tone color information TC is connected to the upper address of the sequence memory 57. In addition to the tone color information, the tone range, touch information, etc. may be input and the tone color may be changed by these as well. In FIG. 6A, the sequence memory 57 has 1
It is an explanatory view showing the format of the sequence data stored corresponding to one tone color information, and shows what harmonic coefficient is used to synthesize a musical tone from the beginning to the end of the musical tone generation. I remember. In reality, there are such data sets as many as the tone color information. In the fields of target D and source S,
Address information (S1, S2 ...) Indicating the harmonic coefficient set stored in the harmonic coefficient set memory 61 is stored, and the number of times of repeated reading of the harmonic coefficient set is normally stored in CON.

The value of CON is input to the comparator 58 and compared with the value of the counter L55. When they match, the output of the comparator 58 becomes 1. This signal is input to the clock terminal of the counter H56 via the AND gate 60 to increment the counter H and clear the counter L55 via the OR gate 54. Further, when CON is 0, the state is controlled until the key is turned off. The NOR gate 59 is 1 when the value of CON is 0.
Then, the FF 52 is reset. Output of FF52 is 0
Then, the AND gates 53 and 60 cause the counter H,
Since the L input signal is cut, the selected address generation unit 20 holds the state until the key-off occurs.

The harmonic coefficient calculation unit 21 performs an interpolation calculation for gradually shifting from the source harmonic coefficient set to the target harmonic coefficient set over the number of times designated by CON. The selector 70 switches the source address SA and the target address DA output from the sequence memory 57 to switch the harmonic coefficient set memory 6
Feed to 1. The harmonic coefficient set memory 61 stores a plurality of harmonic coefficient sets for each tone color, and the format thereof has a structure as shown in FIG. 7A, for example. The figure shows an example in which one harmonic coefficient set is configured by 32 harmonic coefficients. Latches 62 and 63 latch the target harmonic coefficient and the source harmonic coefficient, respectively. The multiplier 64 multiplies the target harmonic coefficient by the output of the converter 69, and the multiplier 65 multiplies the source harmonic coefficient by the output of the complementer 67. An adder 66 adds the outputs of both multipliers 64 and 65 and outputs the interpolated harmonic coefficient to the harmonic memory 22.
Output to.

The divider 68 controls the output value of the counter L to CON.
Divide by the value of. When CON is 0, 0 is output. The converter 69 is a converter using, for example, a ROM for changing the characteristics of the interpolation, and by changing the conversion characteristics according to the timbre, the range, etc., it is possible to make a delicate timbre change. Note that this converter may be omitted. Complementer 6
7 performs an operation such that y = (1−x), where x (0 ≦ x <1) is the output value from the converter and y is the output from the interpolator. That is, x is converted into 2's complement notation to obtain -x, and 1 is added to the value.

FIG. 10 is a waveform diagram showing an example of changes in the waveform and data of the main part during operation of the selected address generator 20. When key-on occurs, both counters H and L are cleared and FF52 is set. Then, the counter L advances by the clock X, and a pulse is generated at the output of the AND 60 at the moment when it becomes equal to the value of CON, the counter H advances, and the output of the comparator 58 clears the counter L. When the counter H steps to k, 0 is output to CON, so the FF 52 is reset and the step is interrupted. When the key-off occurs, the output pulse of EG resets the FF 52 and restarts the step. A value as shown in the figure is output from the divider 68, and interpolation calculation is performed.

FIG. 11 is a waveform diagram showing the waveform of the main part of the harmonic coefficient calculating section 21. In the first half of the basic operation unit (for example, 1 microsecond), the target address DA and the source address S output from the sequence memory 57
A is sequentially output from the selector 70. From the harmonic coefficient set memory 61, the target harmonic coefficient DH and then the source harmonic coefficient SH are sequentially read based on DA, SA, and the harmonic order information Wq, and the latch 62,
63, respectively. Now, assuming that the output of the converter 69 (divider 68) is 1/5, the value of (1-1 / 5) = 4/5 is output from the complementer 67. In the multiplier 64, the target harmonic coefficient DH
Is multiplied by 1/5, and in the multiplier 65, the source harmonic coefficient SH is multiplied by 4/5. The outputs of both multipliers are added by the adder 66, and the interpolated harmonic coefficient Hq is output.

In the harmonic coefficient calculating section 21, if the basic operation unit is repeated by the harmonic order (for example, 32), 1
One harmonic coefficient set is stored in the harmonic memory 22,
If this is repeated for the number of musical sound generation channels (for example, 32), one harmonic order update cycle (hence, the waveform memory 26
Is also the musical sound waveform update cycle of)) ends. Clock x
Can be input at each update cycle in the shortest case, but since the waveform update cycle required to realize the tone color change of the musical tone waveform is generally longer, the clock X is n of the waveform update cycle. The period is set to double (n is an integer of 2 or more). Therefore, during the clock X, the same data operation and update are repeatedly performed. As described above, according to the electronic musical instrument of the present invention, a musical tone waveform whose tone color changes with time can be generated with a very small amount of data as compared with the waveform storage method and without using a circuit such as an envelope generator. It becomes possible to obtain.

Next, another embodiment will be described. Figure 5
FIG. 6 is a block diagram showing a second embodiment of the selected address generator 20. The difference from the first embodiment shown in FIG. 4 is that RTN information as shown in FIG. 6B is added to the sequence memory 57, and if this information is 1, C
The output value of ON is loaded into the counter H, that is, jumped. For this purpose, the counter H
The load terminal LD of the sequence memory 57 is connected to the RTN output of the sequence memory 57, and the preset input terminal of the counter H56 is connected to CON. When the sequence memory 57 in which the information as shown in FIG. 6B is set is used,
Immediately after the value of the counter H reaches n, RTN is set to 1 and CO
The value of N becomes k. Therefore, the counter H is loaded with k, and the data at the address k is output. Since the NOR gate 59 detects that both CON and RTN are 0 and resets the FF 52, the stepping of the counter H can be stopped at the position where CON and RTN are 0 as in the first embodiment. It is possible.

FIG. 8 is a block diagram showing a third embodiment of the selected address generator 20. The difference from the first embodiment shown in FIG. 4 is that, as shown in FIG. 8A, only one target harmonic coefficient set address is stored in one address of the sequence memory 57, and At the time of reading, the plus 1 adder of the address is used to read the coefficient sequentially from two consecutive addresses. FIG. 8B is a block diagram showing the main part of the third embodiment. The output of the counter H56 is input to the +1 adder, and the address one ahead is calculated. The selector 73 sequentially outputs the value of the counter H and the output value of the +1 adder to the sequence memory 57 as addresses, and the latches 74 and 75 latch DA and SA at timings corresponding to the respective addresses. Other operations are the same as those in the first embodiment, and it is possible to stop the stepping of the counter H at the position where CON is 0, for example.

FIG. 9 is a block diagram showing an example in which the present invention is used for giving a temporal change of a formant coefficient. Figure 9
4 is provided in place of the harmonic coefficient calculation unit 21 of FIG. 4, and as shown in FIG. 7B, a formant coefficient set memory 87 storing a plurality of formant coefficient sets.
And the harmonic coefficient Hq or the formant coefficient Fq.
Is output. The HNo → KNo conversion memory 80 determines the harmonic order (first order, second order, ...) At the key number interval (0,
12 ...) (KNo = 12 Log ₂ q). The bias generator 82 generates a predetermined bias value corresponding to the strength of the touch signal. Adders 81 and 83 are key numbers KN
The outputs of the conversion memory 80 and the bias generator 82 are added to o.

The integer part In of the output of the adder 83 is input to the +1 adder 84, and (In + 1) from the +1 adder 84.
Is output. The address signals of the formant coefficient memory 87 are output from the selectors 85 and 86, respectively, and the combination order of the output signals is (In, DA),
(In, SA), (In + 1, DA), (In + 1, S
A). The latches 88 and 89, the multipliers 90 and 91, the adder 92, and the complementer 93 perform the same functions and operations as those of the first embodiment shown in FIG. 4 (although not shown, a divider, Also has a converter). And the integers In and In
The temporal interpolation values corresponding to +1 are sequentially output. Interpolator 9
Reference numeral 4 denotes an interpolation calculation circuit having the same configuration as the block surrounded by a dotted line in FIG. 9, and has a decimal part fr of the key number.
Interpolation calculation is performed based on.

As described above, the information output from the interpolator 94 may be written in the harmonic memory 22 as the harmonic coefficient Hq, but a circuit for generating the harmonic coefficient corresponding to the tone color information is separately provided. Provided, the output of the circuit and the interpolator 9
The harmonic coefficient Hq may be obtained by multiplying the information Fq output from No. 4 by the information Fq.

Although the embodiment has been described above, the following modifications are also possible. The sequence memory may be configured by a RAM, and the CPU may be configured to write the sequence information based on parameters such as tone color. Further, the jump function is not limited to a simple jump, and a conditional jump function such as jumping only when the key is off or a jump function capable of designating the number of jumps can be implemented.

[0026]

As described above, according to the electronic musical instrument of the present invention, the musical tone signal is generated by switching the harmonic coefficient at every predetermined time, so that the arbitrary time of the arbitrary harmonic coefficient is generated. Changes can be easily obtained. In addition, since the same harmonic coefficient set is repeatedly read at a portion where the same harmonic coefficient continues, an increase in the data amount of the harmonic coefficient set is suppressed. Furthermore, if a jump function is added and a specific harmonic coefficient group is repeatedly read out, it is possible to generate a continuous tone with a small amount of data. It is also possible to apply the present invention to the formant coefficient instead of the harmonic coefficient.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a musical tone generating section 6 according to the present invention.

FIG. 2 is a block diagram showing a configuration of an electronic musical instrument to which the present invention is applied.

3 is a block diagram showing a configuration of a waveform calculation section 25 in FIG.

FIG. 4 is a block diagram showing configurations of a selected address generator 20 and a harmonic coefficient calculator 21.

FIG. 5 is a block diagram showing a second embodiment of the selected address generator 20.

FIG. 6 is an explanatory diagram showing a storage format of a sequence memory.

FIG. 7 is an explanatory diagram showing storage formats of a harmonic coefficient set memory and a formant coefficient set memory.

FIG. 8 is a block diagram showing a third embodiment of the selected address generator 20.

FIG. 9 is a block diagram showing an example in which the present invention is used for giving a temporal change of a formant coefficient.

FIG. 10 is a waveform diagram showing an example of changes in waveforms and data of a main part during operation of the selected address generation unit 20.

11 is a waveform diagram showing a waveform of a main part of the harmonic coefficient calculation unit 21. FIG.

[Explanation of symbols]

1 ... CPU, 2 ... ROM, 3 ... RAM, 4 ... Panel section,
5 ... Keyboard part, 6 ... Musical sound generating part, 7 ... D / A converter, 8 ... Analog signal processing part, 9 ... Amplifier, 10 ... Speaker, 11 ... Bus

Claims (5)

[Claims] 1. An electronic musical instrument for synthesizing a musical tone signal based on different harmonic coefficient set information for each tone color, wherein a plurality of harmonics corresponding to at least a part of a musical tone waveform from the start to the end of the generation of one musical tone signal. Harmonic coefficient set storage means for storing a coefficient set, read address generation means for shifting to the reading of the next harmonic coefficient set information after repeatedly reading one harmonic coefficient set information a predetermined number of times, and read address generation means And a musical tone signal generating means for generating a musical tone signal based on the harmonic coefficient set information read by the electronic musical instrument. 2. The harmonic coefficient set storage means also stores read repetition number information corresponding to each harmonic coefficient set, and the read address generation means reads from the harmonic coefficient set storage means. 1 based on the issued repeat count information
The electronic musical instrument according to claim 1, wherein one harmonic coefficient set information is repeatedly read. 3. An interpolating means for performing an interpolating operation for gradually changing the harmonic coefficient information based on the read harmonic coefficient set information and the repetition number information. Item 2. The electronic musical instrument according to Item 2. 4. The electronic musical instrument according to claim 1, wherein the harmonic coefficient set storage means also stores information for jumping to predetermined harmonic coefficient set information. . 5. An electronic musical instrument which synthesizes a musical tone signal based on different formant coefficient set information for each tone color, wherein a plurality of formant coefficient sets corresponding to at least a part of a musical tone waveform from the start to the end of the generation of one musical tone signal. Formant coefficient set storage means for storing, formant coefficient set storage means for reading one set of formant coefficient set information repeatedly for a predetermined number of times, and then for reading the next set information, and formant coefficient read by the read address generation means. An electronic musical instrument, comprising: a musical tone signal generating means for generating a musical tone signal based on set information.