JPS6380297A - Electronic musical instrument - Google Patents

Abstract

(57) [Abstract] 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 an envelope control device for an electronic musical instrument, and more particularly to a device for controlling the shape of the rise (tx) and fall (tx) of an envelope waveform using digital quantities.

Conventional digital envelope generators require a lot of digital information to control, and in order to be able to generate many tones, they require memory to store a large amount of digital information, making them unnecessary. It's the economy. The accuracy of envelope information does not need to be as precise as the accuracy of frequency information, etc., and belongs to the category of being audibly insensitive. Therefore, it is meaningless to increase the accuracy so much regarding the envelope.

However, the time ranges of the envelope length, attack time, decay time, etc. vary from those that change almost instantaneously to those that change over several seconds, so it is necessary to cover a wide i-range. .

Therefore, conventionally, in order to secure this range, we had no choice but to have unnecessary precision and digital information.

The purpose of this application is to improve this shortcoming by using speed parameters to have a wide envelope variation range and to generate many tones with a small storage capacity by compressing all digital information. Our goal is to provide economical and high-performance electronic musical instruments that can perform the following tasks.

Ninth to achieve the above object, the electronic musical instrument of the present invention is an electronic musical instrument that calculates and forms an envelope waveform to be generated in response to a key press, and includes an operator means for externally changing and controlling the time of the generated envelope. and a first converting means for converting the output from the operator means into a speed puff meter having a bit number smaller than the bit number of the calculation value used in the calculation, and storing the speed puff meter from the first converting means. storage means for converting the speed parameter outputted from the storage means into a calculation value used in the calculation; It is characterized by calculation and formation by division.

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

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

In the figure, key information from a keyboard 100 operated by a player is processed by a key assigner 150 and sent to an envelope generation circuit 170. Further, the nine tablets 110 and envelope control volume 120 set by the performer are processed by the tablet data processing circuit 140 and sent to the envelope data control circuit 160, which is the main part of the present invention. The value of the envelope control volume 120 is temporarily changed to the AD converter 15.
It is AD converted by 0 and then sent out. Envelope data control circuit 160 processes the data and sends velocity parameters that determine the shape of the envelope to envelope generation circuit 170. Envelope generation circuit 1
70 calculates an envelope based on the speed parameter and the key information of the key assigner 130 and stores it in the buffer 7 memory 190.
Transfer data to i friend, envelope generation circuit 17
0 temporarily stores the final calculated value of the envelope in memory 1
The data is temporarily stored in 80 as detailed data for time-division calculations, and is used for the next calculation. The buffer 1 memory 190 is repeatedly read out by an execution control circuit 40 (to be described later) at a speed different from the envelope calculation speed, and the data is sent to the DA converter 200. The DA converter 200 converts the digital value of the envelope into an analog voltage to form an envelope waveform.

The envelope generating circuit to which the present invention is applied is disclosed in Japanese Patent Application No. 55
It is preferable to use the envelope waveform full speed parameter of No. 165721 and calculate with a predetermined tying.

FIG. 2 is a diagram illustrating the principle of the previously proposed envelope generating circuit used in the present invention.

In the present invention, the envelope is divided into a plurality of phase ratios, for example, 12 phases (hereinafter referred to as gold phases) as shown in FIG.

The attack part of the envelope is Phase 1 to 7Aze 4.
It is divided into 1.

The release section is represented by phases 5 to 7 aces 8, the state in which the key is pressed is stopped at phase 8, and the release section after the key is released is represented by 12 7 aces from 7 aces 9 to 7 aces 12.

The envelope data is then represented as a floating point number and divided into an exponent and a mantissa as shown in Table 1.

Table 1 In the analogy of Table 9, if the maximum value is 1 or less, the maximum level of the envelope is expressed by the exponent "000" and the mantissa 1"C100J, and if it is 1,000 x 2°t-0db, the minimum level is the exponent "111J, mantissa 1'-aoo" is 1,0O
OX2-' (-424h).

Then, the exponential characteristic of the envelope is formed using this floating point characteristic. That is, the decay and release parts can be easily formed by down-counting the mantissa part and up-counting the finger a part. Also,
The attack portion is obtained by shifting data corresponding to 7 azes using a binary shift circuit, which will be described later.

The above-mentioned method of expressing and forming ADSR using binary floating point numbers is based on Japanese Patent Application Laid-Open No. 1989-1999 proposed by the present applicant.
-1609 "Amplitude generator for electronic organ", so details will be omitted.

In the present invention, the attack, decay, and release lengths are expressed as digital parameters, and these parameters are effectively applied to the envelope calculation means.

9. Considering the release part, in order to allow the release length to vary from 1 millisecond to 3 seconds, this is divided into 9 discrete steps, for example, 52 steps, and each position is represented by 5 bits of a binary number. Then, I send this to the speed parameter decoder as the speed parameter of Enperor 1, and generate a value corresponding to 5LxSC/RT SL; sustain level SC; system clock Cti calculation time) RT; release time. This value means the displacement it- for each calculation cycle included in the release time BT. Therefore, if a different speed parameter is given for each of the 7 aces during release, the release will proceed by 70 displacements during the calculation time involved in the phase agitation. The same goes for Decay.

jgs diagram (αL(&) is an explanatory diagram showing the configuration of the envelope generating circuit 170 shown in 0 deep-FIG. 1, which is particularly relevant to the present invention. FIG. 2 is a block diagram of an envelope generating circuit disclosed in Japanese Patent Application No. 165721/1982.

The numbers for each configuration are the same as the proposed example.

In FIG. 5, the initial values of each phase of ADSR of the envelope explained in FIG. It is used to control the phase transition of required circuits within the system. One of them is the 7-phase closing price prediction circuit 19 where =s5 sustain level data is input, and the predicted value of each phase closing price is sent to the comparator 18, where it is compared with the value from the calculation section described later, and if they match. The coincidence signal is sent to the phase decoder ADSR control circuit 12, 1 is added to the 7-Aze adder 15, stored in the phase memory 10, and sent to the phase decoder ADSR control circuit 12 via the phase initial value generation circuit 11t. Move on to the next phase.

On the other hand, the above-mentioned release part 9 is the change part of the falling time in the decay part t - discretely divided into 52 parts, each position is expressed as a 5-bit speed parameter, and the speed parameter at the required position is processed by a speed parameter decoder. 23
and decode the above sr, x SC/Br'
Generate D value. This decoder 23 and the next binary shift circuit 20 are controlled by the 7-process decoder control circuit 12, and in the case of release and decay, the decoder output passes through the binary shift circuit 20 without shifting, and addition/subtraction control is performed. The signal is sent to the circuit 21 and is controlled by the phase decoder ADSE control circuit 12 to control addition and subtraction to the p calculation section.In the case of IJ and DQ, it operates to add exponents and subtract mantissas. . Adder 16 in the calculation section
The adder 17 stores the exponent and mantissa of Table 1 according to the data from the addition/subtraction control circuit 21, adds and subtracts the data successively output from the nine exponent memory 14 and the mantissa memory 15, and
and is sent to the data selection circuit 24. In the comparator 18, the added nine exponent from the adder 16 and the subtracted nine mantissa from the adder 17 are stored in the phase closing price prediction circuit 19 and compared with the closing price data of each nine, and if there is a match, the calculation is performed until the closing price is exceeded. is repeated.

That is, the exponent from the adder 16 and the mantissa from the adder 17 are input to the data selection circuit 24, and this data is stored again in the exponent memory 14 and the mantissa memory 15 by the control signal of the phase decoder ADSR control circuit 12. do. In this way, calculations are repeated for each phase to form a release/decay whose length corresponds to the above-mentioned 5 bits and corresponds to the friend parameter. Note that the data selection circuit 240
As a function, if the adder 16 overflows, for example, the overflow is detected by the overflow detection circuit 28, and instead of sending the data to the exponent memory 14 and the mantissa memory 15, the memory output is selected.
is controlled by the phase initial amplitude value generation circuit 22 to select and send the next phase initial (if).

Next, in the case of attack, speed parameter decoder 2
3 decoded next data t-binary shift circuit 20
send to If the binary shift circuit 20 shifts the data so as to increase in response to the 7-Aze, a good attack shape can be obtained. In the ninth example, during phase 1, the data from the speed parameter decoder 25 is shifted to the left by t-1 bits, that is, shifted to be multiplied by 4. Next, in phase 2, the data t-1 bits are shifted to the left, that is, shifted to double. In phase 5, it is sent without shifting, and in phase 4, it is shifted to the right by 1 bit.

That is, when set as A, an attack having the shape as shown in FIG. 2 is formed.

The amplitude of each phase of the ADSE of the nine emperogues thus formed is temporarily stored in the exponent memory 14 and the mantissa memory 15 as output data.

A predetermined normal envelope is formed in the above manner, and similarly, a ninth envelope with an amplitude modulation effect is also formed by the same envelope generator. The next amplitude modulation effect practical envelope is formed once the Butts 1 memory 25
is memorized. Here, to create a repeat effect like a marimba, input a predetermined repeating signal as a start signal into the 2nd input of the key data, and create the attenuated sound wave shape OADEi.
By setting the R parameter, the repeat effect practical envelope a-f can be easily obtained.

The tx talessi end effect is created by inputting the logical sum of the O key press signals as the start signal
A similar result can be obtained by setting the DSR parameters.

Next, all calculated normal envelopes are read out from the exponent memory 14 and mantissa memory 15 and sent to the data selection circuit 39, and at the same time, the amplitude modulation effect envelope is read out from the buffer memory 25 under the control of the execution control circuit 40. and sent to the data selection circuit 39.

Here, the normal envelope and the amplitude modulation effect envelope are multiplied, and the multiplication method used in the present invention and which is based on the characteristics of the ADSR generator, which is based on nine floating point arithmetic operations, will be described below.

A ” (1+j!lX2 '+cHX2-"+a@×
2-riX 2-' (1)E: (1+61X2
-'+6fiX2-2+61X2-ri×2″1(2)A
, H can be expressed as a floating point number by converting the binary number t into the following equation (1) <21. This is the first
There are numbers corresponding to Ai.

Now, if we multiply A and Ef, we get the equation (3).

AXjl? = (1+ (a4+6+)Xr' +
(az+b2)X2-"+(am+&s)X2'
+a+ 6+X2-+(s1b2+LL2 bl)X2
″+Ca+bs+azb2+aslB)Xr+Ca2b
s+asb*)×r"+asbHx")x2-""
(3) (3) Formula t-α161xr'' and the following terms are rounded down to (1+(al+6+)
+btnXr'+(a5+63)×r" )×2-(c
(10d)
(41(4) is an approximate expression.

As can be seen from this approximate expression, the multiplication of A and B can be expressed by adding the decimal parts of each mantissa part and adding the exponent parts. According to actual measurements, this truncation error has a maximum error of about ±24E, and it can be assumed that it can be applied to envelope waveforms that are monotonically increasing or monotonically decreasing functions, and even in fc auditory tests. Satisfactory results have been obtained.

The first step of multiplication is the normal ADSR data and the tones that differ depending on the timbre or range of tones described below.
It is multiplied by the loudness data to be output. First, normal ADSR data is selected by the data selection circuit 39 under the control of the execution control circuit 40, and the exponent part is sent to the exponent adder 27 and the mantissa part to the mantissa adder 29.

On the other hand, the data selection circuit 50 selects the 2nd level data under the control of the execution control circuit 40, and similarly the exponent adder 27
and the other input of the mantissa adder 29. The exponent adder 27 adds the exponent parts of the normal ADSE data and the loudness data and sends the result to the exponent subtractor 53. Similarly, the mantissa adder 29 adds the mantissa part and sends it to the two-way 34. If a carry occurs as a result of adding the mantissa parts, a signal is sent to the exponent subtracter 53 to subtract the numerical value 1t by 1 from the calculation result of the exponent part. The exponent subtractor 35 subtracts 1t from the exponent when the carry signal is included, and when not, sends the data as is to the twitch 34. The latch 34 receives the result of these operations t? Finish the step.

Next, as a second step, the above-mentioned result is multiplied by an amplitude modulation effect envelope. As in the 10th step, the data selection circuit 59 is now buffer 1 memo + J25O.
Data is selected and sent to an exponent adder 27 and a mantissa adder 29. Data selection circuit 50 selects the data in latch 34 and sends it to exponent adder 27 and mantissa adder 29. Exponent adder 27. Mantissa adder 29. The exponent subtractor 63 operates in the same manner as in step 1, and the resulting data is latched in the latch 34, and the exponent part is sent to the decoder 31 and the mantissa part to the binary shift circuit 52. The decoder 51 decodes the data of the exponent part and controls the binary shift circuit 52t. If an exponent carry occurs during the calculations in steps 1 and 2, a carry signal is sent from the exponent adder 27 to the overflow detection circuit 26.

The over 70-detection circuit 26 holds this signal and sends it to the decoder 31. For this signal, the exponent part is -7-7=-
If the result is 14, it means a value other than the dynamic range that can be realized. The decoder 31 therefore operates to round the numerical value to the minimum level when this signal is present. 2
The decimal shift circuit shifts the mantissa data based on the signal from the decoder 31, converts the data from a floating point number to a fixed point number, and puffs! Send to memory 190. Bats! The memory 190 temporarily stores this data under the control of the execution control circuit 40. The buffer 7 memory 190 is repeatedly read out by the execution control circuit 40 at a rate different from the calculation rate of the ADSIe generator. The DA converter 200 converts this data into an analog voltage and forms an envelope waveform.

FIG. 5 (&) is a specific circuit example showing the easyness data O input section.

The loudness data is given by the loudness level data stored in the loudness memory 37 and the loudness level data controlled from the outside. Loudness memory 37
is read out based on the frequency information of the operated keyboard and the information of the tone to be formed, and is sent to the data selection circuit 58. The data selection circuit 58 selects this data and the 2nd level data using a data selection signal. The selected 92 noise data is used as described above. Two F
The data of Ness Level Mesosu 37 controls the level by adjusting the frequency of the sound to be played on the keyboard. 2 loudness level data is the tth data that adjusts the volume bounce t'' between tones.This loudness level data 3
7. If you memorize i number of patterns, which is less than the number of tones that can be produced, and perform the aforementioned floating point multiplication from the 2-tone level data to the t-th data of the balance between O tones, the memory will be less than 4 volumes and 1 (2). The system is created economically.

FIG. 4 is a diagram illustrating the configuration of the main parts of the present invention, and shows a detailed block diagram of the envelope control circuit 160 of FIG. 1.

The data processed by the tablet data processing circuit 140 in FIG. 1 is sent to the envelope data control circuit 160 by the tablet data bus in FIG.

The data sent to this data bus includes switch data for the sustain/effect that lengthens the decay time of the sound (this may be different from the sustain level, which indicates the steady state of the envelope); , a knee lever switch that is controlled by the performer's knee, which aims to create a silencing effect similar to that of a damper pedal on a piano, a next-o marimba switch that adds an amplitude modulation effect depending on the tone, a cresciendo switch, and a synthesizer that synthesizes sounds. Switch data such as switches, the sustain/time polymem that adjusts the length of the decay time of the sustain effect mentioned above, the crescendo timepolyme that adjusts the rise time of the sound, and the sound of the synthesizer. attack, decay, sustain, release
-9 digital data such as the volume to be adjusted, and 9 digital numbers added to the tablet switch of the 9 tones that are produced (this is the 2nd grade data called the tone number.The data of each switch mentioned above is the tablet The data is stored in the data memory 50.

FIG. 5(α) illustrates the contents of the tablet data memory 500. Tablet data memory 50 is nine toeha R
The state of each switch is stored at each address (RAMC). For Kutoe, the upper keyboard sustain tablet switch US (hereinafter referred to as VS) is ON.
If 0FIP is 1'6, it is stored as "1", and if 0FIP is 1'6, it is stored as 10.

Below, LS is the lower keyboard sustain tablet, ps is the foot keyboard sustain tablet, pss is the percussion sound (piano-like decay sound sustain tablet,
B! L is a sustain tablet for brass and woodwind sounds, K
L Honey Lever and MA Hamarimba are tablets for practical use with amplitude variation that repeats attenuated sounds, CE is a tablet for Talessiendo effect (increasing the sound gradually), and SY is a synthesizer tablet. As described above, the state of each tablet switch is stored by the memory control circuit 55.

Next, the aforementioned volume value is stored in the polyneme value memory 58, and the contents of the polyneme value memory 58 are shown in FIG. 5(6).
Illustrated in Here, UST indicates the upper keyboard sustain time. LET is the lower keyboard sustain time,...
...The following is the same as above. Furthermore, 5YAT is the attack time of a synthesizer.

5YDT is the decay time, 5YEH is the sustain level (steady sound level), and EIYRT is the release time.

The scale and timbre number data are written into the timbre number memory 52 by the memory control circuit 55.

This tone number is a rough number assigned to each of multiple tones, for example, and has a mechanism that allows them to selectively produce one tone. There are two series of B.

Next, the contents of the buffer 7 memory 61 are shown in FIG. 5 (#).

Here, UP-°°Upper keyboard flute type UO...I Orchestra type (tone series such as strings) LF...Lower keyboard flute type LO...I Orchestral type PF...Pedal keyboard flute type po...・ l Orchestral PS...Percussion S/Yon B...Plus system (Brass Woodwind MA...Marimba effect CE...Cresciendo effect SY...Synthesizer, with attack, decay, and sustain, respectively) , release, and loudness data.This buffer 7 memory 61 is composed of Em.

Next, to explain the envelope data control circuit 160, assuming that 67t is processed sequentially from address D in FIG. In addition, the memory control circuit 55 has a buffer 1 memory 6.
Specify address 1 of 0. Address 0 is the memory area for attack parameter data in the UP.

Next, the memory control circuit 55 sends a signal to the envelope data memory succession circuit 53. The envelope data memory output circuit 53 sends an address signal to the envelope data memory 54 and envelope data control memory 56.

The contents of the envelope data memory 54 are shown in FIG. 5(6), and the contents of the envelope data control memory 56 are shown in FIG. 5(d). Envelope data memory 54
The attack parameter data of the UF is read out using the aforementioned address signal and sent to the data selector 0.

At the same time, a ninth signal for controlling envelope data is read from the envelope data control memory 56 and sent to the envelope data selection control circuit 51. This signal is represented by 1 bit, and the envelope data memory 5
The data box stored in the envelope data memory 54 is a rounding signal for selecting at of the polyneme stored in the polynomial value memory 58. If this signal is "0", the contents of the envelope data memory 54 are t-, " 1″, the polyme value memory 58
operates to select the contents of.

The envelope data selection control circuit 51 converts the above-mentioned signal into 1
data from the tablet data memory 50 as another input. Tablet data memory 5
0 is a signal from the memory control circuit 55 and 1 is read out. The envelope data selection control circuit 51 sends these two inputs to a logical product tube and a data selector 60, for example. If you look at nine, the US of tablet data memory 50 is 1.
If the attack control data of the UF in the envelope data control memory 56 is "mouth", the output signal of the emphasizing data selection circuit 51 becomes "0" and the output of the envelope data memory 54 of the data selector 60 is selected. In this way, the data selector 60 sends the attack parameter data to the buffer 1 memory 61, and writes the data to the address of the attack parameter data of the UF in the buffer 7 memory 61 in response to the write signal from the memory control circuit 55. .

Similarly, each data of the decay parameter, sustain level, and 2nd density level is -i! F is inserted.

On the other hand, if the signal read from the envelope data control memory 56 during release parameter processing O is "1",
The AND of i in the envelope data selection control circuit 51 and the signal from the tablet data memory 50 becomes 11, and the data selector 60 selects the data in the conversion circuit 59. The poly/z-me value memory 58 reads out the value of UST by the memory control circuit 55 and sends the data to the conversion circuit 59. The conversion circuit 59 has a plurality of conversion circuits with different characteristics, and the memory control circuit 55 specifies which characteristic to use. In this way, the data from the polygon value memory 58 is converted and sent to the data selector 60.
and written to buffer 7 mesosu 61. As a result, the release time of the UF is controlled by the polyisland. Data such as O and below are written.

On the other hand, for the percussion system and the plus system, the timbre number stored in the timbre number memory 520 is read out by the memory control circuit 55 and sent to the envelope data memory continuation circuit 53. The envelope data memory succession circuit 53 determines which data t-of PS or B in the envelope data memory 54 is to be read out based on this tone color number. The data is then processed in the same way as the method described above.

If KL in the tablet data memory 50 is "1", even if it is ff, U3. A signal is sent to the envelope data selection control circuit 51 so that PS and BS are 1"K, and it works to perform a logical sum with each signal. In this way, the decay time can be controlled not only by the tablet but also by the knee lever. .

If HA is @11 and 6, perform the same processing as F, and if it is +, write the EFFECT OFF data in the envelope data memory 54 to the buffer memory 61. This adds an effect. The same goes for CB. When SY is "1", 5YAT in the variable value memory 61 is set.

Each data of 5YDT, 5YJL, and 5YRT is written through the conversion circuit 59t'.

Next, the phase data is sent from the envelope generation circuit 170 of FIG. 1 to the memory control circuit 55. Addressing of the buffer memory 61 is executed by this 7Aze data and a signal from the execution control circuit 40. For example, data in the buffer 1 memory 61 is read out, such as attack parameter data during the attack phase and decay parameter data during the decay phase, and the necessary data is sent to the envelope generation circuit 170 via the data selector 57. be sent in a time-sharing manner.

Next, if the keyboard is pressed more than the number of channels that can be sounded, the key assigner 130 detects this, reads out the phase data of each channel from the 4 o'clock storage memory 180 connected to the envelope generation circuit 170, and selects the most advanced phase data. Detects the channel, calculates the envelope of that channel, and sends a request signal to the memory control circuit 5 in the envelope data control circuit 16G in synchronization with the sulting.
Send to 5.

Memory control circuit 55 sends a signal to data selector 57 to select high speed parameter data. In this way, the channel can be quickly released by sending parameter data such that the sound attenuation ends at a high speed to the envelope generator 17o.

Next, loudness control will be explained.

The two-tone level data in the envelope data memory 54 is composed of 8 bits each, with the MSB being a control bit and the lower 7 bits being data.

It becomes a data selection signal, and the lower 7 bits become 2nd level data. If this control bit is "0", the data selection circuit 5B selects the loudness level data. Next, when the control bit is 0, the data selection circuit 38 selects the output of the loudness memory 57. 2. The sound memory 37 is the key assigner 15 in FIG.
Frequency information from 0 (a certain i is the keyboard information that is pressed and i is read out as timbre information. This timbre information is 9, for example, when the aforementioned control bit is 0, the lower 7 of that data If the timbre information is stored in the bit, the 2nd input of the timbre information will consist of the same line as the loudness level data line.

In the embodiment, each data read from the buffer 7 memory 61 is transferred to the fifth 'IA (
a) sent to the envelope generation circuit 170 at +(6), and ADSR in the envelope generation circuit 170;
Parameter data, Nasteen level bar/) meter,
/F loudness level data The aforementioned data is distributed to the human power, and a latch circuit is required to latch each data sent in a time-sharing manner. The drawing describes it as a trout.

As explained above and as follows, according to the present invention, the envelope waveform is expressed using the previously proposed velocity parameter, this is stored in the storage means, and this velocity parameter is sequentially displayed in a time-division manner to determine the rise of the envelope. The next step is to time-divisionally calculate the falling 5o shape. This eliminates the need for numerous CB circuits and CR oscillators that determine the shape of the envelope, as well as complex configurations such as the accumulators and clock generation circuits that were proposed to improve this, making it much simpler and cheaper. It can be configured as follows. It is possible to generate as many envelopes as possible, which are calculated in a time-division manner, and also to generate envelopes for sliding 7 orthogonals at the same time using one envelope generator. Note that since all envelope data is digitally controlled, it is suitable for integrated circuits and miniaturization.

[Brief explanation of the drawing]

FIG. 1 is a schematic explanatory diagram of an electronic musical instrument to which the present invention is applied;
The figure is an explanatory diagram of the principle of an envelope generator to which the present invention is applied, FIG. 5(,) to (#) show specific examples of the contents of each memory in the configuration of FIG. 4. In the figure, 40 is an execution control circuit, 50 is a tablet data memory, 51 is an envelope data selection control circuit, 52 is a 9-color number memory, 53 is an envelope data memory successive circuit, 54 is an envelope data memory, and 55 is a memory. a control circuit; 56 is an envelope data control memory;
57 is a data selector, 58 is a volume value memory, 59
1 is a conversion circuit, 60 is a data selector, 61 is a buffer 7 memory, 160 is an envelope control circuit, and 17o is an envelope generation circuit. Patent applicant Kawai Musical Instruments Co., Ltd. Representative Patent attorney 1) Yoshishige Saka ＼ Audience J-BeΔhehe 1 ol'lt

Claims (2)

[Claims] (1) In an electronic musical instrument that calculates and forms an envelope waveform to be generated in response to a key press, an operator means for changing and controlling the time of the generated envelope from the outside, and an output from the operator means is used for the calculation. a first conversion means for converting the speed parameter into a speed parameter having a smaller number of bits than the number of bits of the calculated value; a storage means for storing the speed parameter from the first conversion means; and a speed parameter outputted from the storage means. An electronic musical instrument comprising: a second converting means for converting parameters into calculated values used in the calculation; and calculating and forming an envelope waveform in a time-sharing manner based on the calculated values from the second calculating means. (2) A patent characterized in that the first conversion means has a plurality of different conversion characteristics, and is a conversion means that selects an optimal conversion characteristic according to the musical tone generation sequence and converts it into the speed parameter. An electronic musical instrument according to claim 1.