JPH07248765A - Electronic musical instrument - Google Patents

Abstract

PURPOSE:To generate stereophonic sound without increasing the size of the constitution and to select stereophonic or monaural musical sound for each musical sound generator. CONSTITUTION:In accordance with the control of a read address control circuit 53, any one of first to third musical sound waveform data are read out of first and second waveform data memories 51 and 52, a gate circuit 58 is controlled by selection information S/M which is set for every musical sound generator. Further in accordance with whether the second musical sound waveform data read out of the memory 52 are shut off by the circuit 58 or not, each of right and left musical sound waveform data generating circuits 54 and 55 selectively generate stereophonic or monaural musical sound. Thus, there is not need to provide each two of a waveform reading and generating circuit and a waveform data memory which are required for a conventional device and the selection of stereophonic or monaural musical sound is controlled for every musical sound generator.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to electronic musical instruments, and in particular,
It is suitable for use in an electronic musical instrument capable of selectively generating either a stereo musical tone or a monaural musical tone by using a waveform reading and generating circuit.

[0002]

2. Description of the Related Art In electronic musical instruments such as electronic pianos, electronic keyboards, synthesizers, etc., performance can be performed by operating keys on a keyboard section. The musical tone generated during this performance is generated by using a plurality of types of musical tone waveform data stored in advance in the waveform data memory inside the electronic musical instrument.

That is, first, when a player operates a key on the keyboard section, the above-mentioned operation is performed based on the key information indicating the operation state and the tone parameter information such as the tone color set by each operator of the operation panel section. The corresponding tone waveform data is read out from the waveform data memory. And
The read musical tone waveform data is processed to generate a desired musical tone. The process of reading and processing the tone waveform data is performed by the waveform read generation circuit.

FIG. 7 is a block diagram showing an example of a conventional configuration of a musical tone generating section provided with the above waveform reading and generating circuit and waveform data memory. In FIG. 7, reference numeral 20 denotes a waveform data memory in which various musical tone waveform data corresponding to tone color, tone range, touch information regarding the operation speed of each key, and the like are stored in advance. Then, according to the address information given to the input terminal AB in a time division manner, the musical tone waveform data corresponding to the address information is outputted from the output terminal DB.

Further, the output enable terminal OE of the waveform data memory 20 is connected to a low level so as to keep the output state at all times. When the output enable terminal OE is connected to the high level, the output of the waveform data memory 20 becomes high impedance.

Next, reference numeral 30 is a waveform reading and generating circuit, which is usually constituted by a large scale integrated circuit (LSI) as one block. That is, the waveform read generation circuit 30 includes the constituent elements 31 as described below.
˜34 and 301 to 309 are integrated and configured on one block.

Below, the configuration of each of the constituent elements 31 to 34, 301 to 309 in the waveform reading and generating circuit 30 will be described in detail, while using the tone waveform data stored in the above waveform data memory 20 to digitally The operation of generating a musical tone signal of the form will be described.

First, among the constituent elements of the waveform reading and generating circuit 30, reference numeral 33 is an input / output terminal for various signals, which is connected to a signal bus composed of an address bus, a data bus, a control signal line and the like. As a result, the waveform read generation circuit 30 causes the other circuit (eg, CP (not shown) for controlling the entire electronic musical instrument to configure the electronic musical instrument.
U) can transmit and receive data to and from each other via the signal bus.

Address information and various data input from the CPU to the input / output terminal 33 via the address bus and the data bus are supplied to the CPU interface 301. Then, under the control of the CPU interface 301, various data necessary for generating a desired musical tone signal is written in a specific position in the parameter memory 302 designated by the address information.

That is, in the parameter memory 302, the same number m as a plurality of tone generators provided to enable a plurality of tones to be generated simultaneously.
Only the stage is equipped. Then, the various data described above are written at specific positions of each of these stages.

Here, the data written in the parameter memory 302 is, for example, the key-on / key-on obtained as a result of the assignment processing by the CPU according to the key depression / key release of each key.
OFF information, the key number assigned to each key to identify the pressed key, or the waveform readout section to determine the readout area and readout method of the tone waveform data.
For example, a method designation signal. Then, the various data written in the parameter memory 302 in this way are output to each circuit of the next stage in a time division manner according to the system sequence.

Of the various data output in time division, the key number of the depressed key is the frequency number memory 3
03. In this frequency number memory 303, a numerical value (frequency number) corresponding to a desired musical tone frequency is stored in advance for each key number of each key. The frequency number corresponding to the key number supplied from the parameter memory 302 is stored in the frequency number memory 30.
3 and is supplied to one input terminal of the frequency number calculator 304 in a time division manner.

The frequency number calculator 304 accumulates the frequency numbers sent from the frequency number memory 303 in a time division manner, and stores the accumulated value in the address value memory 305. The accumulated value thus stored in the address value memory 305 is supplied to the frequency number calculator 304 as a feedback value for performing the next accumulation.

As a result, the frequency number calculator 304
Is obtained by adding the current frequency number supplied from the frequency number memory 303 to one input terminal and the accumulated value up to the previous time fed back from the address value memory 305 to the other input terminal. , Generate a new accumulated value.

The frequency number calculator 304 is
According to the read section / method designation signal supplied from the parameter memory 302, the position at which the musical tone waveform data to be read is stored and the method of reading the musical tone waveform data (for example, an address loop method) are defined. . As a result, the frequency number calculator 304 generates the above-described accumulated value of the frequency number according to such a rule.

The address value memory 305 has the same number of stages m as the plurality of tone generators, like the parameter memory 302 described above. The parameter memory 302 is used for writing and reading data.
The time division is performed according to the system sequence described above so as to be synchronized with the writing and reading of data in the envelope memory 307 described later. Similarly, the envelope memory 307 has the same number of stages m as the plurality of tone generators, and the writing and reading of the data are performed in a time division manner according to the system sequence.

Next, the integer part of the accumulated value of the frequency numbers generated as described above is used as address information for designating the reading position of the musical tone waveform data, through the address output terminal 31, the waveform data memory. 20 input terminals AB
Are supplied in a time-sharing manner. As a result, the corresponding tone waveform data is read from the output terminal DB of the waveform data memory 20 according to the address information corresponding to the integer part of the accumulated value. The musical tone waveform data thus read is interpolated by the interpolator 308 via the waveform data input terminal 32.
Is supplied to one of the input terminals.

The decimal part of the accumulated value of the frequency number is supplied to the other input terminal of the interpolator 308 as an interpolation coefficient for sample-interpolating the tone waveform data read from the waveform data memory 20. Then, the interpolator 308 interpolates the musical tone waveform data read from the waveform data memory 20 with an interpolation coefficient according to the decimal part of the accumulated value. As a result, the noise of the musical tone waveform data is reduced.

On the other hand, of the various data output from the parameter memory 302 in a time division manner, the key on / off information and the key number are supplied to one input terminal of the envelope calculator 306. Also, the envelope calculator 30
The other input terminal of 6 is fed back with the current value of the envelope generated by the previous calculation and stored in the envelope memory 307.

Then, the envelope calculator 306 performs a predetermined calculation on the current value of the envelope according to the key on / off information and the key number, and, for example, the attack, decay, and suspension corresponding to each range. Teen,
A new envelope operation value with release is generated. The calculated value of the envelope thus generated is stored in the envelope memory 307 as a feedback value for performing the next calculation, and the multiplier 309
Is supplied to one of the input terminals.

At the other input terminal of the multiplier 309,
The tone waveform data subjected to the interpolation processing by the interpolator 308 is supplied. The amplitude of the musical tone waveform data is controlled by multiplying the musical tone waveform data supplied to the other input terminal by the envelope value supplied to the one input terminal. The musical tone waveform data subjected to the amplitude control in this manner is output as a digital tone signal through the tone signal output terminal 34 to the D / A converter provided in the next stage.

[0022]

In the conventional electronic musical instrument, a desired musical tone is generated in accordance with the above-mentioned waveform reading method (usually called the PCM method). Further, in recent years, stereophonization of generated musical tones has come to be implemented. Conventionally, the generation of this stereo musical tone has been performed by providing two waveform data memories 20 and two waveform read generation circuits 30 shown in FIG.

That is, as shown in FIG. 8, two first and second waveform data memories 20A and 20B are provided as memories corresponding to the waveform data memory 20 of FIG. Further, as a circuit corresponding to the waveform read generation circuit 30, a first waveform read generation circuit 30A and a second waveform read generation circuit 30A are provided.
Two waveform read generation circuits 30B are provided. And
By operating the first waveform read generation circuit 30A and the second waveform read generation circuit 30B together, a stereo musical tone is generated.

As described above, the conventional electronic musical instrument is designed to generate stereo musical tones by simply doubling all the components required to generate musical tones. Even if it is wonderful, there is a problem that its configuration becomes large and the cost becomes very high.

As described above, the selection of whether to generate a stereo musical tone or a monaural musical tone is performed by operating the second waveform read generating circuit 30B together with the first waveform read generating circuit 30A. That is, that is, whether or not all the circuits inside thereof are operated collectively. Therefore, in the conventional electronic musical instrument, since a plurality of musical sound generators are collectively controlled, it is not possible to control the selection of stereo musical sound or monaural musical sound for each musical sound generator.

The present invention has been made in order to solve such a problem, and it is possible to selectively generate either a stereo musical sound or a monaural musical sound without making the structure large. In addition, the purpose is to enable selection of stereo tones or monaural tones for each tone generator.

[0027]

In the electronic musical instrument of the present invention, the first musical tone waveform data used for generating a stereo musical tone and the third musical tone waveform used for generating a monaural musical tone.
Waveform data storage means having first waveform data memory means for storing the musical tone waveform data of No. 2 and second waveform data memory means for storing the second musical tone waveform data used for generating stereo musical tones. A read address control circuit for generating address information for reading any of the first to third tone waveform data from each of the first waveform data memory means and the second waveform data memory means; According to the address information generated by the read address control circuit, using the first and second musical tone waveform data read from the first and second waveform data memories, a right musical tone which is one of stereo musical tone waveform data. Waveform data is generated or the third tone waveform data is read from the first waveform data memory. Data is read from the first and second waveform data memories in accordance with the first musical tone waveform data generating circuit for generating monaural musical tone waveform data using a computer and the address information generated by the read address control circuit. A second musical tone waveform data generating circuit for generating left musical tone waveform data which is another one of the stereo musical tone waveform data by using the first and second musical tone waveform data is provided, and the read address control circuit is controlled. To read any one of the first to third musical tone waveform data from each of the first and second waveform data memories, and use the read musical tone waveform data to determine whether it is stereo musical tone waveform data or monaural musical tone waveform data. One of the above is selectively generated.

Another feature of the present invention is that the second waveform data memory read from the second waveform data memory according to the content of selection information for selecting either a stereo musical tone or a monaural musical tone. A gate circuit for passing or blocking the musical tone waveform data is provided, and either the stereo musical tone or the monaural musical tone is selectively selected depending on whether or not the second musical tone waveform data is blocked by the gate circuit. It is something that is generated.

Still another feature of the present invention is that
The contents of the selection information can be set for each of a plurality of tone generators provided so that a plurality of tones can be simultaneously generated.

[0030]

According to the present invention configured as described above, the first and second tone waveform data are read from the first and second waveform data memories respectively in accordance with the address information generated by the read address control circuit. When generated, stereo musical tones are generated by the first and second musical tone waveform data generating circuits, and when the third musical tone waveform data is read from the first waveform data memory, the first musical tone waveform is generated. Since the data generation circuit can generate a monaural tone, it becomes possible to selectively generate either a stereo tone or a monaural tone with a single waveform read generation circuit, which is the same as in the conventional method. It is possible to generate a stereo musical sound without providing two circuits and two waveform data memories.

According to another feature of the present invention, the second tone waveform data read from the second waveform data memory is not blocked by the gate circuit to generate a stereo tone waveform, or the second tone waveform is generated. By shutting off the musical tone waveform data of No. 1 by the gate circuit, a monaural musical tone waveform is generated using only the first musical tone waveform data. It is possible to selectively generate one of the monaural musical sounds.

Furthermore, according to another feature of the present invention,
By controlling the gate circuit according to the content of the selection information set for each tone generator, it is possible to control the selection of stereo tones or monaural tone for each tone generator.

[0033]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is a block diagram showing the elemental characteristics of a musical tone generating section including a waveform read generating circuit in an electronic musical instrument of the present invention. First, the configuration of the musical sound generating unit will be described with reference to FIG.

In FIG. 1, reference numeral 51 is a first waveform data memory, which stores first musical tone waveform data used to generate stereo musical tones and third musical tone waveform data used to generate monaural musical tones. Plural types are stored in a predetermined storage area. A second waveform data memory 52 stores a plurality of types of second stereo tone waveform data used for generating stereo tones.

Next, reference numeral 50 is a waveform read-out generation circuit, which is composed of the circuits 53 to 58 described below. That is, in the configuration of the waveform read generation circuit 50, reference numeral 53 is a read address control circuit, which is provided with predetermined information (for example, key on / off information detected in response to key press / release of the keyboard, key number, etc.). Address information for reading out necessary musical tone waveform data from the first waveform data memory 51 and the second waveform data memory 52.

Next, reference numeral 54 is a right-side tone waveform data generation circuit, which produces first and second waveform data memories 51 and 52 when stereo tones are generated. Using the musical tone waveform data of, the right musical tone waveform data forming the stereo musical tone is generated.

The right tone waveform data generation circuit 5 is also used.
When a monaural tone is generated, 4 generates monaural tone waveform data by using either the first tone waveform data or the third tone waveform data read from the first waveform data memory 51.

Next, reference numeral 55 is a left musical tone waveform data generating circuit, which produces first and second waveform data memories 51 and 52 when stereo musical tones are generated. Using the musical tone waveform data, left musical tone waveform data forming a stereo musical tone is generated.

The left tone waveform data generation circuit 5 is also used.
Reference numeral 5 generates monaural tone waveform data by using either the first tone waveform data or the third tone waveform data read from the first waveform data memory 51 when a monaural tone is generated.

Next, 56 is a right envelope generating circuit, which is a right envelope waveform for controlling the amplitude of the right tone waveform data generated by the right tone waveform data generating circuit 54, or a monaural tone waveform data. Generates a monaural envelope waveform for controlling the amplitude of.

Next, reference numeral 57 is a left envelope generating circuit, which controls the left envelope waveform for controlling the amplitude of the left tone waveform data generated by the left tone waveform data generating circuit 55, or the amplitude of the monaural tone waveform data. To generate a monaural envelope waveform.

Next, 58 is a gate circuit, which is a selection signal S / set by an S / M selection switch 6c (a switch for selecting either stereo or monaural) provided on the operation panel section 6. Depending on the content of M, the second musical tone waveform data read from the second waveform data memory 52 is passed or blocked.

By the way, the waveform reading and generating circuit 50 of the present embodiment has a plurality of musical tone generators and can generate a plurality of musical tone waveform data at the same time. The selection signal S / M described above is prepared as one element in various parameter sets set for each of these tone generators. As a result, a stereo musical tone or a monaural musical tone can be selected for each musical tone generator according to the setting content of the selection signal S / M.

Next, the operation of generating stereo musical tone waveform data or monaural musical tone waveform data with the above configuration will be described. First, when the performer operates the keyboard to perform a performance, key information detected in response to the key operation is given to the read address control circuit 53. And
The read address control circuit 53 causes the first and second waveform data memories 51 and 52 to store the first waveform data.
Address information for reading out necessary musical tone waveform data from the third musical tone waveform data is generated based on the key information.

Then, the read address control circuit 53
The address information generated in 1 is given to the first waveform data memory 51 and the second waveform data memory 52.
As a result, the first and second waveform data memories 5
From 1, 52, musical tone waveform data corresponding to the address information is read.

Here, in the case of generating a stereo tone, the first tone waveform data is read from the first waveform data memory 51, and the first tone waveform data is converted from the second waveform data memory 52 into the first tone waveform data. The corresponding second tone waveform data is read out.

The first musical tone waveform data thus read is given to both the right musical tone waveform data generating circuit 54 and the left musical tone waveform data generating circuit 55. Also, the second
The musical tone waveform data of No. 2 passes through the gate circuit 58 as it is and is given to both the right musical tone waveform data generating circuit 54 and the left musical tone waveform data generating circuit 55.

Then, the right musical tone waveform generating circuit 54 uses the first musical tone waveform data and the second musical tone waveform data to generate one right musical tone waveform data forming a stereo musical tone. Further, the left musical tone waveform data generation circuit 55 uses the first musical tone waveform data and the second musical tone waveform data to generate the other left musical tone waveform data that constitutes a stereo musical tone.

Further, each of these tone waveform generating circuits 5
The right and left musical tone waveform data generated at 4 and 55 are amplitude-controlled by the right envelope waveform supplied from the right envelope generating circuit 56 and the left envelope waveform supplied from the left envelope generating circuit 57, respectively.

The right musical tone waveform data and the left musical tone waveform data whose amplitudes have been controlled as described above are D / A converters provided in the next stage as digital musical tone signals for generating stereo musical tones. (Not shown).

On the other hand, when a monaural tone is generated, the first waveform data memory 51 according to the address information given from the read address control circuit 53.
To read only the third tone waveform data.

The thus-read third tone waveform data is applied to both the right tone waveform data generation circuit 54 and the left tone waveform data generation circuit 55. Then, each of these tone waveform generating circuits 54 and 55 generates monaural tone waveform data based on the given third tone waveform data.

Furthermore, each of these tone waveform generating circuits 5
The two monaural tone waveform data generated in 4, 55 are the right and left envelope generating circuits 5 respectively.
Amplitude control is performed by the monaural envelope waveforms given from 6, 57. As a result, the left and right of the two monaural tone waveform data generated by the tone waveform data generation circuits 54 and 55 are balanced.

The two monaural musical tone waveform data generated as described above are D / A converters (not shown) provided in the next stage as digital musical tone signals for generating monaural musical tones. Is output to.

The above-mentioned musical tone waveform data generating circuit 5 is used.
Since the two monaural tone waveform data generated at 4, 55 are the same as each other, the monaural tone waveform data may be generated by only one of the tone waveform data generating circuits.

Further, the waveform read generation circuit 50 of the present embodiment.
, The S / M selection switch 6c of the operation panel section 6
Is operated to change the setting content of the selection signal S / M, it is possible to arbitrarily select a stereo tone or a monaural tone for each tone generator.

That is, in this embodiment, the selection signal S
The gate circuit 58 is controlled by the setting contents of / M, and the second
By passing or blocking the second musical tone waveform data read from the waveform data memory 52, the stereo musical tone or the monaural musical tone can be arbitrarily selected for each musical tone generator. .

For example, when the second musical tone waveform data passes through the gate circuit 58 as it is, the first musical tone waveform data generating circuit 54 for the right and the musical tone waveform data generating circuit for the left 55 are respectively provided with the first musical tone waveform data. Both the tone waveform data and the second tone waveform data are given. Therefore, in this case, since the right musical tone waveform data and the left musical tone waveform data are generated in the respective circuits, the generated musical tone becomes a stereo musical tone.

On the other hand, when the second tone waveform data is cut off by the gate circuit 58, each of the tone waveform data generating circuits 54, 55 has the first waveform data memory 51 which reads the first tone waveform data. Only one tone waveform data will be given. In this case, since the tone waveform data generating circuits 54 and 55 generate tone waveform data based only on the first tone waveform data,
The musical tone waveform data generated by the one musical tone waveform data generation circuits 54 and 55 are the same. Therefore, the generated musical sound is a monaural musical sound.

Here, the selection signal S / M is prepared as one element in the parameter set set for each tone generator, and is externally operated by operating the S / M selection switch 6c. The contents can be set arbitrarily. Therefore, since the operation of the gate circuit 58 can be controlled for each tone generator, it is possible to control for each tone generator whether it is a stereo tone or a monaural tone.

FIG. 2 is a block diagram more specifically showing the configuration of the musical tone generating section shown in FIG. 1. FIG. 3 shows a schematic configuration of the entire electronic musical instrument in which the musical tone generating section is implemented. It is a block diagram.

First, in the electronic musical instrument shown in FIG.
U1, ROM2, RAM3, keyboard section 5, operation panel section 6 and tone generation section 7 are respectively provided with an address bus,
It is configured to be connected to a signal bus 4 such as a data bus and a control signal line so that data can be mutually transmitted and received.

Here, the keyboard portion 5 is composed of one or a plurality of keyboards including a plurality of keys for performing a performance and a key switch provided corresponding to each of the keys. The key switch is configured to detect a key press and a key release as well as a key operation speed.

The operation panel section 6 is provided with various operators for setting rhythm, tone color, volume, effect, etc., and an LCD (liquid crystal display device) for displaying the setting state of these.
Alternatively, in addition to a display device including an LED (light emitting diode), a switch for selecting whether to generate a musical sound in stereo or monaural is provided. Note that FIG. 3 shows a tone color setting switch 6a for setting a tone color.
, A volume 6b for setting the volume, and an S / M selection switch 6c for selecting stereo tones or monaural tones.

Next, the CPU 1 is a central processing unit for controlling the entire electronic musical instrument, and executes the following processes according to the control program stored in the ROM 2 while using the RAM 3 as a work memory. For example, the CPU 1 performs a scan process of each key switch of the keyboard unit 5 and a scan process of each operator of the operation panel unit 6 to obtain key information (key on / key off) accompanying key depression / release of each key.
OFF information, key number, touch information relating to key operation speed, etc.) and the operation state of each operator of the operation panel unit 6 are detected.

Then, the key information detected as described above is assigned to the musical tone generator provided in the musical tone generating section 7, and the tone color and volume set by the tone color setting switch 6a and the volume 6b are set. A process for generating a desired musical tone signal from the musical tone generating section 7 is performed according to the musical tone parameter information.

The ROM 2 is a read-only memory and stores various data necessary for generating a desired musical tone signal from the musical tone generating section 7 in addition to the control program of the CPU 1 described above. There is.

The RAM 3 is a readable / writable memory, and has a storage area for temporarily storing various necessary data during the program execution process of the CPU 1 and storing data obtained as a result of various processes. Have A part or all of the RAM 3 is backed up by a battery so that necessary data corresponding to the tone color set by the tone color setting switch 6a can be retained even when the power of the electronic musical instrument is turned off. Has been done.

Next, the musical tone generating section 7 is provided with a plurality of musical tone generators for generating a musical tone signal with a tone color set by the operation of the tone color setting switch 6a according to a depressed key. Then, the musical tone generating circuit 7 determines, based on the key information or the like given in response to the pressing of any key.
Musical tone waveform data is read from a waveform data memory described later, and the read musical tone waveform data is processed to generate a digital tone signal.

The digital tone signal generated by the tone generator 7 is applied to the D / A converter 8 and converted into an analog tone signal. As the D / A converter 8, one or a plurality of D / A converters are used depending on whether a monaural tone or a stereo tone is generated.

The analog tone signal thus D / A converted is subjected to simple filter processing (noise removal processing) and amplification processing in the analog signal processing section 9, and then amplified to an appropriate level in the power amplifier 10. It is given to the speaker 11. The speaker 11 is for emitting the given analog musical tone signal as an audible signal,
It is composed of one or more.

In the configuration of the musical tone generating section 7 shown in FIG. 2, reference numeral 101 is a first waveform data memory, which is musical tone waveform data recorded or synthesized to generate a stereo musical tone. Tone waveform data (R +) obtained by adding the tone waveform data for left and the tone waveform data for left.
L) and a plurality of tone waveform data (M) for generating monaural tone are stored.

Reference numeral 102 denotes a second waveform data memory, which is musical tone waveform data recorded or synthesized to generate a stereo musical tone, and is a musical tone sound obtained by subtracting the right musical tone waveform data and the left musical tone waveform data. Plural types of waveform data (RL) are stored.

Next, reference numeral 100 is a waveform read-out generation circuit, which is usually constructed by forming an ASIC (application specific integrated circuit). The waveform read generation circuit 100
Is an improvement of the conventional waveform read generation circuit 30, and only those necessary for explaining the features of the present embodiment are illustrated in a simplified manner.

Of the constituent elements of the waveform read generation circuit 100, 103 is a CPU interface, and the parameter memory 10 designated by the address information input from the address bus via the signal input / output terminal 118.
4 is for writing various data input from the data bus via the input / output terminal 118 to a specific position.

Here, FIG. 4 shows an example of the contents of the parameter memory 104 in which the above various data are written. That is, the parameter memory 104 is provided with the same number of stages m as the plurality of tone generators described above, and each stage has key on / off information, a key number, a waveform readout section / method designation signal. , Selection signal S / M,
And other parameters are written.

The above-mentioned key on / off information is the information obtained as a result of the assigning process by the CPU 1 according to the key press / release of each key of the keyboard section 5, and the key number is the key pressed. It is a number attached to each key to identify the key. The waveform readout section / method designation signal is information for determining the area to be read out of the musical tone waveform data and the reading method.

The selection signal S / M is information for controlling whether a stereo musical tone or a monaural musical tone is generated by controlling the operation of the gate circuit 108 described later. Further, the other parameters include right loudness control information RL for controlling the volume of the right tone, and left loudness control information LL for controlling the volume of the left tone.

Next, a read address generator 105 receives the key on / off information, the key number and the read section / method designation signal from the parameter memory 104, and uses these pieces of information to obtain a desired musical tone. Find the frequency. Then, based on the tone frequency thus obtained, the following two pieces of information s1 and s2 are output.

That is, the read address generator 105
Is an integer value of the musical tone frequency obtained as described above as address information s1 for reading out the desired musical tone waveform data at the desired musical tone frequency, via the address output terminal 119 for each waveform data memory 101, Output to 102. In addition, the first interpolator 109 and the second interpolator 110 are used as the interpolation coefficient s2 for performing the sample interpolation on the tone waveform data read from the waveform data memories 101 and 102 by using the decimal value of the tone frequency. Supply to.

Next, reference numeral 106 denotes an R envelope generator, which generates a right envelope waveform used when a stereo tone is generated or a monaural envelope waveform used when a monaural tone is generated. Here, the R envelope generator 106 responds to the change in the operation state of the key in accordance with the key on / off information, the key number, and the right loudness control information RL supplied from the parameter memory 104, and outputs the generated musical tone. Volume is right loudness control information R
It produces an envelope waveform which is controlled entirely by L and whose range is controlled by the key number.

Next, 107 is an L envelope generator which generates a left envelope waveform used when a stereo musical tone is generated or a monaural envelope waveform used when a monaural musical tone is generated. Here, the L envelope generator 107 responds to a change in the operation state of the key in accordance with the key on / off information, the key number, and the left loudness control information LL supplied from the parameter memory 104, and generates the sound volume of the musical tone. Is the left loudness control information L
It produces an envelope waveform which is controlled entirely by L and whose range is controlled by the key number.

Next, reference numeral 108 denotes a gate circuit, which is a musical tone read from the second waveform data memory 102 through the second waveform data input terminal 121 in response to the selection signal S / M supplied from the parameter memory 104. Waveform data (RL) is supplied to the second interpolator 1 provided in the next stage.
Pass or block 10 as it is.

For example, the gate circuit 108 uses the selection signal S
When / M is 1 (when a stereo tone is generated), the tone waveform data (RL) read from the second waveform data memory 102 is passed through as it is and supplied to the second interpolator 110. Further, when the selection signal S / M is 0 (when a monaural tone is generated), the tone waveform data (RL) read from the second waveform data memory 102 is cut off, and the second interpolator 110 outputs " Supply 0 "data.

Next, 109 is a first interpolator, which uses the first waveform data memory 101 to generate the first waveform by the interpolation coefficient s2 corresponding to the decimal value of the tone frequency supplied from the read address generator 105. Data input terminal 12
The tone waveform data (R + L) or (M) read via 0 is sample-interpolated.

Further, the second interpolator 110 described above is read from the second waveform data memory 102 by the interpolation coefficient s2 supplied from the read address generator 105 and supplied via the gate circuit 108. The musical tone waveform data (RL) to be sampled is sample-interpolated.

Next, 111 is a first adder, which is the musical tone waveform data sample-interpolated by the first interpolator 109 and the musical tone waveform data sample-interpolated by the second interpolator 110. Is added to generate one of the right musical tone waveform data or the monaural musical tone waveform data forming the stereo musical tone.

For example, when the selection signal S / M is 1 (when a stereo tone is generated), the musical tone waveform data (R + L) supplied from the first interpolator 109 and the second interpolator 110 are supplied. By adding the tone waveform data (R−L), the right tone waveform data 2R (= (R + L) +
(RL)) is generated.

When the selection signal S / M is 0 (when a monaural tone is generated), the data supplied from the second interpolator 110 is "0" data, and therefore the first interpolator 109 is used.
The musical tone waveform data (R + L) or (M) supplied from is directly supplied to the first shift circuit 114 in the next stage.

Next, reference numeral 112 denotes a complementer, which obtains the 2's complement of the musical tone waveform data (RL) subjected to the sample interpolation by the second interpolator 110 to obtain the musical tone waveform data [-(R- L)] is generated.

Next, reference numeral 113 denotes a second adder, which combines the musical tone waveform data sample-interpolated by the first interpolator 109 and the musical tone waveform data two-complemented by the complementer 112. By adding, the other left tone sound waveform data or monaural tone sound waveform data forming the stereo tone is generated.

For example, when the selection signal S / M is 1 (when a stereo tone is generated), the tone waveform data (R + L) supplied from the first interpolator 109 and the tone waveform data supplied from the complementer 112 are supplied. [-(R-L)] is added to the left musical tone waveform data 2L (= (R + L)-
(RL)) is generated.

When the selection signal S / M is 0 (when a monaural tone is generated), the data supplied from the second interpolator 110 is "0" data, and therefore the first interpolator 109 is used.
The tone waveform data (R + L) or (M) supplied from is directly supplied to the second shift circuit 115 in the next stage.

Then, the first shift circuit 114 described above is used.
Is a circuit for halving the tone waveform data supplied from the first adder 111, and its operation is controlled by the selection signal S / M supplied from the parameter memory 104.

That is, the first shift circuit 114, when the selection signal S / M is 1 (when a stereo musical tone is generated), the musical tone waveform data (2R) generated by the first adder 111.
Is shifted to ½ to generate musical tone waveform data (R), which is supplied to the first multiplier 116. When the selection signal S / M is 0 (when a monaural tone is generated), the tone waveform data (R + L) or (M) supplied from the first adder 111 is used as the first multiplier 1
16 as it is.

Then, the second shift circuit 115
1/2 of the tone waveform data supplied from the adder 113 of
This is a circuit for multiplying, and is the parameter memory 104.
The operation is controlled by the selection signal S / M supplied from

That is, the second shift circuit 115, when the selection signal S / M is 1 (when a stereo musical tone is generated), the musical tone waveform data (2L) created by the second adder 113.
Is shifted to ½ to generate tone waveform data (L), which is supplied to the second multiplier 117. When the selection signal S / M is 0 (when a monaural tone is generated), the tone waveform data (R + L) or (M) supplied from the second adder 113 is used as the second multiplier 1
Supply to 17 as it is.

Next, when the selection signal S / M is 1 (when a stereo tone is generated), the first multiplier 116 outputs the amplitude of the right tone waveform data (R) supplied from the first shift circuit 114. Are controlled by the right envelope waveform supplied from the R envelope generator 106.

When the selection signal S / M is 0 (when a monaural tone is generated), the amplitude of the tone waveform data (R + L) or (M) supplied from the first shift circuit 114 is changed to the R envelope generator. It is controlled by the monaural envelope waveform supplied from 106. Then, the musical tone waveform whose amplitude is controlled as described above is output to the D / A converter 8 provided in the next stage via the first output terminal 122.

Next, the second multiplier 117, when the selection signal S / M is 1 (when a stereo tone is generated), the left tone waveform data (L) supplied from the second shift circuit 115.
Is controlled by the left envelope waveform supplied from the L envelope generator 107.

When the selection signal S / M is 0 (when a monaural tone is generated), the amplitude of the tone waveform data (R + L) or (M) supplied from the second shift circuit 115 is changed to the L envelope generator. It is controlled by the monaural envelope waveform supplied from 107. Then, the musical tone waveform whose amplitude is controlled as described above is output to the D / A converter 8 provided in the next stage via the second output terminal 123.

Next, the operation of the musical tone generating section configured as described above will be described with reference to FIGS.

First, when the performer operates each operator of the operation panel section 6 shown in FIG. 3 to set the volume of the generated musical sound and whether the sound is stereo or monaural, the waveform read section is set in accordance with the setting contents. Method designation signal, right loudness control information RL, left loudness control information LL, selection signal S /
Each information such as M is given to the musical sound generating section 7 via the signal bus 4. Then, the respective information given in this way is shown in FIG.
It is stored in a specific position in the parameter memory 104 via the CPU interface 103 of the.

When the player operates each key of the keyboard section 5 shown in FIG. 3, the key on / off corresponding to the key operation is performed.
Key information such as OFF information and a key number is given to the musical sound generating section 7 via the signal bus 4. Then, the key information thus provided is stored in a specific position in the parameter memory 104 via the CPU interface 103 of FIG.

Next, of the information stored in the parameter memory 104, the key on / off information, the key number, and the read section / method designation signal are supplied to the read address generator 105, where a predetermined calculation is performed. Is performed, the musical tone frequency corresponding to each information given to the read address generator 105 is obtained.

The integer part of the musical tone frequency thus obtained is used as the address information s1 for reading out the necessary musical tone waveform data, and the first waveform data memory 101 and the second waveform data are outputted via the address output terminal 119. It is provided to the memory 102. The fractional part of the tone frequency is given to the first interpolator 109 and the second interpolator 110 as an interpolation coefficient s2 for performing sample interpolation.

Here, in the storage area of the first waveform data memory 101, when the position where the musical tone waveform data (R + L) is stored is designated by the address information s1, the musical tone waveform data (R + L). Is read from the first waveform data memory 101, and the tone waveform data (R−L) corresponding to the tone waveform data (R + L) is read.
L) is read from the second waveform data memory 102.

The tone waveform data (R + L) read from the first waveform data memory 101 is supplied to one input terminal of the first interpolator 109 via the first waveform data input terminal 120. It Thus the first interpolator 1
09, the tone waveform data (R
+ L) is the interpolation coefficient s given to the other input terminal
After the sample interpolation is performed by 2, the first adder 1
11 and the second adder 113, respectively.

On the other hand, the second waveform data memory 102
The tone waveform data (R-L) read from is supplied to one input terminal of the gate circuit 108 via the second waveform data input terminal 121. This gate circuit 108
Is controlled according to the selection signal S / M given to the other input terminal. When the selection signal S / M is 1 (when a stereo musical tone is generated), the tone waveform data (R -L) is directly supplied to one input terminal of the second interpolator 110.

The tone waveform data (RL) given to one input terminal of the second interpolator 110 is sample-interpolated by the interpolation coefficient s2 given to the other input terminal, and then sampled. It is supplied to the other input terminal of the adder 111 of 1 and is also supplied to the complementer 112. Then, the musical tone waveform data (R-
L) is converted into musical tone waveform data [-(RL)] by being subjected to 2's complementation, and the second adder 113
Is supplied to the other input terminal.

Next, the first adder 111 causes the first interpolator 109 and the second interpolator 11 to operate as described above.
Music waveform data (R + L) and (R-
L) is added to generate musical tone waveform data (2R). The musical tone waveform data (2R) is converted to musical tone waveform data (R) by being halved by the first shift circuit 114, and then supplied to one input terminal of the first multiplier 116. It

By the way, at the other input terminal of the first multiplier 116, the key ON / OFF information in the parameter memory 104, the key number and the right loudness control information RL are input.
The right envelope waveform generated by the R envelope generator 106 based on the above is given. Then, the amplitude of the musical tone waveform data (R) supplied to the one input terminal is controlled by the envelope waveform for the right side, and the musical tone waveform data (R) is D / A converted in the next stage as a digital musical tone signal for the right side. Output to the container 8.

Further, in the second adder 113, the musical tone waveform data (R + L) and [-(RL)] supplied from the first interpolator 109 and the complementer 112 are added,
Musical tone waveform data (2L) is generated. Then, the musical tone waveform data (2L) is set to 1 by the second shift circuit 115.
After being multiplied by / 2 to be converted into musical tone waveform data (L), it is supplied to one input terminal of the second multiplier 117.

By the way, at the other input terminal of the second multiplier 117, the key ON / OFF information, the key number and the left loudness control information LL in the parameter memory 104 are provided.
The left envelope waveform generated by the L envelope generator 107 based on the above is given. The amplitude of the musical tone waveform data (L) supplied to the one input terminal is controlled by the left envelope waveform, and the musical tone waveform data (L) is used as a left digital musical tone signal in the D / A converter 8 of the next stage. Is output to.

After that, with respect to each of the right and left digital tone signals generated as described above, the D / A converter 8, the analog signal processing section 9 and the power amplifier 10 shown in FIG. Such processing is performed, and a stereo musical sound is generated from the speaker 11.

On the other hand, when the selection signal S / M applied to the other input terminal of the gate circuit 108 is 0 (when a monaural tone is generated), the tone waveform data (R-L) read from the second waveform data memory 102 is read. ) Is cut off by the gate circuit 108, and "0" data is supplied to the second interpolator 110.

In this case, the first interpolator 109 outputs the musical tone waveform data (R + L) read from the first waveform data memory 101, and the second interpolator 110 outputs "0" data. Is output. Therefore, the tone waveform data generated by the first adder 111, the first shift circuit 114, and the first multiplier 116 and the complementer 112,
The tone waveform data generated by the second adder 113, the second shift circuit 115, and the second multiplier 117 are all (R + L).

As described above, when the selection signal S / M is set to 0 by the operation of the S / M selection switch 6c of the operation panel section 6, the first multiplier 116 and the second multiplier 117 are operated. Each tone waveform data output from each is
Both are musical tone waveform data of the same type. As a result, D /
A converter 8, analog signal processing unit 9, power amplifier 10
The musical sound generated from the speaker 11 through each process in 1 is a monaural musical sound.

By the way, as described above, the gate circuit 10
The selection signal S / M given to 8 can be set for each tone generator. Therefore, by setting the selection signal S / M for each tone generator and controlling the gate circuit 108, the selection between stereo tone generation and monaural tone control is controlled for each tone generator. be able to.

The read address generator 105 described above is also used.
When the position in which the musical tone waveform data (M) is stored is designated from the storage area of the first waveform data memory 101 by the address information s1 given from, the musical tone waveform data (M) is the first Waveform data memory 101
Read from. In this case, no tone waveform data is read from the second waveform data memory 102.

In this case, the tone waveform data (M) is output from the first interpolator 109 and the second interpolator 110 is output.
Will output "0" data. Therefore, the musical tone waveform data generated by the first adder 111, the first shift circuit 114, and the first multiplier 116,
The tone waveform data generated by the complementer 112, the second adder 113, the second shift circuit 115, and the second multiplier 117 are all (M).

Thus, the first waveform data memory 10
When the musical tone waveform data (M) is read from 1, the musical tone waveform data output from each of the first multiplier 116 and the second multiplier 117 is the same type of musical tone waveform data. . As a result, the musical sound generated from the speaker 11 through the processes in the D / A converter 8, the analog signal processing unit 9, and the power amplifier 10 becomes a monaural musical sound.

When a monaural tone is generated in this way, the tone waveform data output from the two multipliers 116 and 117 are the same.
The complementer 112, the second adder 113, the second shift circuit 115, and the second multiplier 117 may not be used. In this way, power consumption can be saved.

As described above, in the electronic musical instrument according to this embodiment, the circuit portion for generating either the right musical tone waveform data (R) or the monaural musical tone waveform data (M) and the left musical tone are provided inside. And a circuit portion for generating waveform data (L). Then, the musical tone waveform data to be supplied to each of these circuit portions is first divided in accordance with the address information generated by the read address generator 105.
By controlling the waveform data memory 101 and the second waveform data memory 102 to be read from a predetermined storage area, either a stereo musical tone or a monaural musical tone can be selectively generated. Therefore, unlike the conventional case, it is not necessary to provide two waveform read generation circuits and two waveform data memories in order to generate stereo musical tones, and it is possible to generate stereo musical tones with a simple configuration. it can.

In this embodiment, the S / M selection switch 6c of the operation panel section 6 is operated to select the selection signal S / M.
The gate circuit 108 is controlled by setting
By passing or blocking the musical tone waveform data (RL) read from the waveform data memory 102, the stereo tone sound or the monaural tone sound is selectively generated. Therefore, similarly to the above, it is possible to generate a stereo musical tone without providing two waveform reading generation circuits and two waveform data memories, and it is possible to generate a stereo musical tone with a simple configuration. it can.

Further, in the present embodiment, since the selection signal S / M can be set for each tone generator, one tone generator can generate a stereo tone or a monaural tone. It is possible to control the selection of stereo tones and monaural tones for each tone color.

Thus, for example, with respect to the tone color of a piano or the like in which a sound with added value is obtained by generating a stereo musical tone, the stereo musical tone is generated, and even if the stereo musical tone is generated, there is no great effect. It is possible to generate a monaural tone for a tone color that can obtain a sufficient effect even with a monaural tone.

FIG. 5 is a conceptual diagram showing respective operations in the case where a stereo musical tone or a monaural musical tone is generated in accordance with the target tone color as described above. Of these, FIG. 5A shows a case where a stereo tone is generated, and FIG. 5B shows a case where a monaural tone is generated.

As shown in FIG. 5A, when a stereo tone is generated, first, the first waveform data memory 101 and the second waveform data memory 101 are generated according to the address information s1 output from the read address generator 105. From 102, musical tone waveform data (R + L) and (R-L) are read.

Next, the tone waveform data (R + L) and (R-L) thus read out are subjected to predetermined processing by the circuits 108 to 115 shown in FIG. Data (R) and (L) are generated.
Of these, the musical tone waveform data (R) is the first multiplier 11
6, the amplitude is controlled by the right envelope waveform given from the R envelope generator 106, and is output as a right digital tone signal.

The amplitude of the musical tone waveform data (L) is controlled by the second multiplier 117 by the left envelope waveform given from the L envelope generator 107, and is output as a left digital musical tone signal.

On the other hand, as shown in FIG. 5B, when a monaural tone is generated, first, the read address generator 10
5 based on the address information s1 output from the first waveform data memory 101, only tone waveform data (M)
Is read. Next, the musical tone waveform data (M) thus read is subjected to a predetermined process in each of the circuits 108 to 115 to generate two musical tone waveform data (M).

Then, these two musical tone waveform data (M) are converted into the first multiplier 116 and the second multiplier 11 respectively.
7, the amplitude is controlled by the monaural envelope waveforms supplied from the R envelope generator 106 and the L envelope generator 107, and the monaural digital musical tone signal is output.

When the monaural tone is generated, the monaural envelope waveforms given from the R envelope generator 106 and the L envelope generator 107 respectively balance the left and right of the two tone waveform data (M). It functions as a signal for taking.

Furthermore, according to the electronic musical instrument of this embodiment, as described above, it is possible to control whether each musical tone generator generates a stereo musical tone or a monaural musical tone, so that one musical tone is generated. When generated by two or more tone generators, it is possible to select a stereo tone sound or a monaural tone sound for each tone generator.

For example, as shown in FIG. 6, consider a case where one tone of tone color A is generated by using two tone generators i and i + 1. In this case, the musical sound of tone color A is the partial sound a.
And partial sound b, of which partial sound a is generated by the tone generator i. Further, the partial sound b is a musical sound generator i +
It is generated by 1.

The partial sounds a and b generated by the tone generators i and i + 1 are added to each other by the adders 130 and 131 and output. At this time, each partial sound a, b
Is controlled so that the amplitude and the like differ according to the touch information of the key and the passage of time. As a result, the tone color of the tone color A is changed in accordance with the touch information and the passage of time. In this case, the musical tones generated by the musical tone generators i and i + 1 can be controlled in three combinations as shown in Table 1 below.

[0138]

[Table 1]

In the embodiment described above, the first waveform data memory 101 and the second waveform data memory 102.
Has a hardware configuration separate from that of the musical tone waveform data (R + L) and the musical tone waveform data (R) by one address information s1 given from the read address generator 105.
-L) and are read.

However, the present invention is not limited to this. For example, both musical tone waveform data (R + L) and (R−L) are stored in different storage areas in one waveform data memory. Then, the read address generator 10
Two pieces of address information are generated from the integer part of the tone frequency obtained in 5, and two pieces of tone waveform data (R + L) and (R-L) stored in the different storage areas are generated by using the two pieces of address information thus generated. ) And may be read.

Further, in the above-mentioned embodiment, the selection signal S / M for controlling the stereo tone sound or the monaural tone sound is set according to the operation of the S / M selection switch 6c. It may be automatically set according to the tone color set by the operation of the switch 6a. For example, for a tone color having a sufficient added value in generating a stereo tone such as a piano tone, a tone color with which the selection signal S / M is automatically set to 1 and a sufficient effect is obtained even with a monaural tone. For selection signal S
/ M may be automatically set to 0.

In the above description, the envelope waveform generated by the envelope generator (envelope calculator and envelope memory) corresponds to the attack, decay, and It is said that the waveform has sustain and release, but the shape of the envelope waveform is also changed according to the selected timbre. The loudness control information is also controlled according to the selected tone color.

[0143]

As described above, according to the present invention, the first musical tone waveform data generating circuit for generating the right musical tone waveform data or the monaural musical tone waveform data and the left musical tone sound are generated in one waveform reading and generating circuit. A second musical tone waveform data generation circuit for generating waveform data is provided, and a read address control circuit controls a position for reading musical tone waveform data from each of the first waveform data memory and the second waveform data memory. Thus, any one of the musical tone waveform data is read out from the first to third musical tone waveform data, and either a stereo musical tone or a monaural musical tone is selectively generated according to the read musical tone waveform data. Therefore, it is possible to generate a stereo musical sound without providing two waveform reading generation circuits and two waveform data memories as in the conventional case. It becomes possible way. Therefore, it is not necessary to increase the size of the structure for generating stereo tones, and the cost can be reduced.

According to another feature of the present invention, the first tone waveform data and the second tone waveform data read from the first waveform data memory and the second waveform data memory, respectively.
Among the musical tone waveform data of No. 2, the stereo musical tone or the monaural musical tone is selectively generated according to whether or not the second musical tone waveform data is cut off by the gate circuit. In addition, it becomes possible to generate stereo musical tones with one waveform reading and generating circuit, and it is possible to reduce the cost.

Further, according to another feature of the present invention,
Since the contents of the selection information for controlling the operation of the gate circuit can be set for each of a plurality of musical tone generators, it is possible to select a stereo musical tone or a monaural musical tone according to a desired musical tone waveform. It becomes possible to control for each tone generator, and it is possible to control selection of stereo tone and monaural tone for each tone color. Further, when one musical tone is generated by two or more musical tone generators, stereo musical tone or monaural musical tone can be selected for each of these musical tone generators, and the degree of freedom of selection can be increased. it can.

[Brief description of drawings]

FIG. 1 is a block diagram showing the elemental features of a musical tone generation section including a waveform read generation circuit in an electronic musical instrument of the present invention.

FIG. 2 is a block diagram showing a configuration of a musical sound generating section in the electronic musical instrument which is an embodiment of the present invention.

FIG. 3 is a block diagram showing a schematic configuration of the entire electronic musical instrument in which the musical sound generating unit of the present embodiment is implemented.

FIG. 4 is a diagram showing an example of data stored in a parameter memory inside a waveform read generation circuit.

FIG. 5 is a conceptual diagram showing a case of generating a stereo musical tone and a case of generating a monaural musical tone.

FIG. 6 is a conceptual diagram showing a case where one musical sound is generated by two musical sound generators.

FIG. 7 is a block diagram showing a configuration of a conventional musical tone generating section.

FIG. 8 is a diagram showing a conventional configuration for generating stereo tones.

[Explanation of symbols]

 1 CPU 2 ROM 3 RAM 4 signal bus 5 keyboard section 6 operation panel section 6a tone color setting switch 6b volume 6c S / M selection switch 7 tone generation section 8 D / A converter 9 analog signal processing section 10 power amplifier 11 speaker 50 waveform Read generation circuit 51 First waveform data memory 52 Second waveform data memory 53 Read address control circuit 54 Right tone waveform data generation circuit 55 Left tone waveform data generation circuit 56 Right envelope generation circuit 57 Left envelope generation circuit 58 Gate Circuit 100 Waveform read generation circuit 101 First waveform data memory 102 Second waveform data memory 103 CPU interface 104 Parameter memory 105 Read address generator 106 R envelope generator 107 L envelope generation Unit 108 gate circuit 109 first interpolator 110 second interpolator 111 first adder 112 complementer 113 second adder 114 first shift circuit 115 second shift circuit 116 first multiplier 117 Second multiplier

Claims (3)

[Claims] 1. A first waveform data memory means for storing first musical tone waveform data used for generating a stereo musical tone and third musical tone waveform data used for generating a monaural musical tone, and a stereo musical tone. Waveform data storage means having second waveform data memory means for storing second tone waveform data used to generate the waveform, and each of the first waveform data memory means and the second waveform data memory means. From the read address control circuit for generating address information for reading any of the first to third musical tone waveform data from the above, and the first and second waveforms according to the address information generated by the read address control circuit. The stereo tone waveform data is read using the first and second tone waveform data read from the data memory. A first tone waveform for generating right tone waveform data, which is one of the above, or for generating monaural tone waveform data using the third tone waveform data read from the first waveform data memory. According to the address information generated by the data generation circuit and the read address control circuit, stereo musical tone waveform data is generated using the first and second musical tone waveform data read from the first and second waveform data memories, respectively. A second musical tone waveform data generation circuit for generating the other musical tone waveform data for left is provided, and the first to second waveform data memories are controlled by the read address control circuit. Any of the third musical tone waveform data is read out, and the read musical tone waveform data is used to determine whether it is stereo musical tone waveform data. An electronic musical instrument characterized in that any one of monaural tone waveform data is selectively generated. 2. The electronic musical instrument according to claim 1, wherein the second waveform data memory reads the second waveform data memory in accordance with the content of selection information for selecting either a stereo musical tone or a monaural musical tone. A gate circuit for passing or blocking musical tone waveform data is provided, and either a stereo musical tone or a monaural musical tone is selectively selected depending on whether the gate circuit blocks the second musical tone waveform data. An electronic musical instrument characterized by being generated. 3. The electronic musical instrument according to claim 2, wherein the content of the selection information is set for each of a plurality of musical tone generators provided so that a plurality of musical tones can be simultaneously generated. An electronic musical instrument characterized by being made.