JPS5830796A - Electronic musical instrument - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an electronic musical instrument that allows a plurality of musical sound waveforms with different tones to be read out simultaneously.

FIG. 1 shows a musical sound waveform reading device used in a conventional electronic musical instrument. In FIG. 1, an address counter 1 counts clock pulses from a read clock generator 2 and supplies the count value to a waveform memory 3 as an address control signal. With this address control signal, the musical sound waveform stored in advance in the waveform memory 3 is read out as a digital value, which is converted by the D/A conversion circuit 4 from a gauge value of 3.-7 to an analog value. is output from the speaker 7 through the amplifier 6.

However, in order to simultaneously produce a plurality of different tones using such a waveform reading device, a plurality of the devices shown in FIG. The drawback was that the entire system became large-scale.

The present invention provides an electronic musical instrument that eliminates the drawbacks of the conventional example.

Embodiments in which the present invention is applied to a rhythm sound source that generates sounds such as drums and percussion will be described below with reference to the drawings.

FIG. 2 shows the overall configuration of a rhythm performance device using the present invention. The rhythm selection means 8 includes march, rock,
It consists of a switch that selects the rhythm of Manpohiro. The tempo specifier 9 is composed of an oscillator that generates a clock for specifying the basic tempo at which the rhythm is played. The rhythm pattern generating means 16 inputs the input information from the rhythm selecting means 8 and the tempo specifying means 9, and also determines the timing at which rhythm instruments such as bass drums, snare drums, bongos, etc. should be played according to this input information.
Further, depending on the case, tones such as accent and mute are instructed to the seat address control means 11 by counting the clocks from the tempo specifying means 9.

On the other hand, the time-division readout control means 12 supplies the address control means 11 with control information for specifying a readout timing predetermined by the musical instrument.

The address control means 11 supplies an address control signal corresponding to the read timing to the waveform memory 3 based on information from the rhythm pattern generation means 10 and the time-division read control means 11.

Waveform information based on digital data outputted from the waveform memory 3 is converted into an analog value by a D/A conversion circuit 9, passed through a clock removal filter 4 and an amplifier 6, and then outputted from a speaker 7.

Next, the address control means 11 and time-division read control means 12, which are the core of this embodiment, will be explained together with a specific circuit.

The waveform memory 3 contains the bass drum shown in Table 1.

Four types of instrument sounds, snare drum, cowpel, and bongo, are pre-written in 12-bit PCM.

(Left below) 6-1 The address of the bass drum is in hexadecimal from "oooo" (hereinafter written as 0000H) to 07FFH.

2o48 addresses (1 address is 12 pits of data)
The read speed is 20 KHz, or 50 μB, and the data length is 102.4 mg. Similarly, for the snare drum, the address is 2 from 08ooH to 0FFFH.
048 address, read speed is 40KHz or 2
0 Cowbell, which is 6 μB and has a data length of 61.2 mg, stores data for two tones corresponding to the open playing style and muted playing style at addresses 1oooH to 13FFH and 1400H to 17FFH "t" (7) 10247.
)"t, ', the read speed can be switched between 40KHz and 20KHz, and the data length is 40Ktlz.
26.6 m t+ at time, 51.2 at 20 KHz
mg. By switching the reading speed, it is possible to switch between a loud, low-pitched caravel sound and a small, high-pitched caravel sound.

For bongos, the data of two tones, high pitch and low pitch, are each 1800H7)k to IBFFH4 and IC0.
It has a 1o24 address from OH to I FFFH,
Read speed is 20KHz, data length is 51.2mB
It is.

In order to simultaneously sound the musical tone data of the four types of musical instruments written in the waveform memory 3 as described above, one cycle T is divided into four equal parts by the time division readout control means 12 as shown in FIG. T2. Create T3 and set To interval, that is, φ
When 1 is 0 and φ2 is 0, the bass drum, T1 (φ1-
1 and φ2-0) is the snare drum, T2 (φ1=0 and φ2-1) is the caravel, T3 (φ1=1 and φ2=1)
) as bongo.

This is shown in a concrete circuit in Figure 4, 16
The outputs obtained by dividing the 0KH2 clock by two ÷2 counters are respectively φ1. It becomes φ2.

On the other hand, if, for example, you want to sound the bass drum and -caravel at the same time, as shown in Figure 6, after reading the data of a, which is the waveform of the bass drum, into the Dooi interval TO, the data of b, which is the waveform of the caravel, is read out. D21i is read in interval T2, and in the same way, Dol, D21, and next cycle K are read in the next cycle.
It is sufficient to read them one after another in time division, such as DO2 and D22.

Corresponding to the time intervals To, TI, T2, and T3 determined by the time-division readout control means 12 in this way,
The address control means controls the readout speed, tone color switching, data length switching, and on/off (whether or not to produce sound) control for the waveform memory 3 for each assigned musical instrument. It is 11.

Here, a concrete block diagram of the address control means 11 is shown in the sixth section.
As shown in the figure.

The waveform memory 3 is a C8 that controls whether to output data to the 13th address input (8192 address) from AO to Al2 and output or set it to an offset value (AC 0 level).
There is an input.

The upper two bits (A11.Al2) of the address are connected to the time division signal from the time division read control means 12,
Switch the address corresponding to each instrument in Table 1. On the other hand, a readout address counter 131° connected to the output of the time-division readout control means 12 supplies the readout speed switching means 14 and the data length switching means 16 with addresses for reading out all waveforms of each musical instrument.

The readout speed switching means 14 selects the address for reading out the waveform of the instrument corresponding to the time interval based on the time interval information from the time division readout control means 12, and selects the address of the lower 10 bits of the waveform memory 3 ( By connecting to A○ to A9), the reading speed can be changed. The tone color switching means 16 reads out all 2048 addresses like the bass drum and snare+°ram in Table 1, or reads out two tones at 1024 addresses like the caravelle and bongos, that is, the 11th bit A10 of the address. 'i Switch for each time interval for each instrument.

The data length switching means 16 is connected to the read address counter 1.
Based on the information from 3.25. of the data length shown in Table 1.
6mg, 51.2mg, and 102.4mg are switched for each time interval for each instrument, and after the predetermined data length is read out, information that prohibits waveform reading is stored in the waveform memory 3.
is supplied to the C8 terminal of the Oh 11,, knee.

The on/off control means 17 controls whether each musical instrument should produce sound (on) or not produce sound (off).

The off information is supplied to the C3 terminal of the waveform memory 3 in the same way as the data length switching means 16.

Next, FIG. 7 shows a circuit that is a more specific block diagram of the address control means.

The read address counter 13 is operated by the 13-, b-1f counters 18 and the inhibit gate 19, and when the reset signal is released, the read address counter 13 counts up the clock signal φ2 of the time-division read control means 12, and counts up the clock signal φ2 of the time division read control means 12, Output QO~
When Q12 is output and counts 4096, the output Q12 becomes high level (hereinafter abbreviated as "H"), the inhibit gate 19 inhibits the siccant clock, and this state is maintained until the next reset is applied.

The read speed switching means 14 is a read speed selection MPX.
(multiplexer) 20, an inverter 21, and a selection matrix 22. Read speed selection MPX20 is
Clock signal φ1. from time division read control means 12.
Based on φ2, set @L” with a reading speed of 20KH2 for TO (bass drum) and T1 (snare drum).
For 40KHz 1H'', for T2 (Caravelle),
40KH2 and 20K from the rhythm pattern generating means 10
Hz switching information, T3 (pump), 20K) I
'L' of z is output respectively.

Next, the operation of the selection matrix 22 will be explained using FIG. 8. 8. Orthogonal line A shown in FIG.

The circle mark at the intersection of C, B, and D means an AND gate, and the diagonal line E means an OR gate, and when converted into a logic diagram, it becomes like b. In other words, when A is “H” and B is “L”, the output E =
When A is "L" and B is "H", the output E=D and a selection operation is performed.

In this way, the selection matrix 22 selects the output QO' of the 13bif counter 18 (40KHz output such as z waveform memory address input Ao, Ql to A1, etc.) when the output of the read speed selection MPX 20 is 'H'. Connect read address. Also read speed selection MPX
When the output of inverter 20 is °L'', the output of inverter 21 is '
H"tonashi, Q113 -,.

to AO, Q2 to A1, etc. 20. KHz
tT) Connect read address.

The timbre switching means 16 can be realized by the timbre switching MPX 23, and the φ1. The necessary tone color is switched based on φ2.

In the time intervals To and T2, that is, the bass drum and snare drum, by connecting the output of the selection matrix 22 to A10 of the uppermost full waveform memory 3, all 2048 addresses are read out. In time intervals T2 and T3, that is, caravelle and bongo, by connecting the tone switching information from the rhythm pattern generating means 1o to A10, the 10
Two tones are selected and read out for each 24 addresses.

The data length switching means 16 includes an inverter 24, a NOR gate 26, 26, a selection matrix 27, and a data length switching M
Consists of PX28. As shown in FIG. 9, the output of the inverter 24, which is the inverse of 012, is 102.4 ms, Qll
and Ql2. The output of the NOR gate 25 with a large input 'r is 51.
2 ms,, 51.2 ms signal inversion and 010
The output of the manually operated NOR gate 26 is "H" for each period of 25.6 mg, and becomes 'L' after that period. To (bass drum) is 102.4m5i, T1 (snare drum) is 51.2ylsi, T2 (caravelle) is the output of selection matrix 27, and T3 (bongo) is 51.2ms'.
z Select and output.

The selection matrix 27 changes the data length in accordance with the pitch change of the caravel, and as explained in FIG. 8, when reading at 40KHz, the data length is 25.6mg, and when reading out at 20KtlzO, the data length is 61.271s. and connected to the data length switching MPX.

The on/off switching means 17 can be realized by an on/off switching MPX 29, and the φ of the time division readout control means 42
1. Based on φ2, on/off information from the rhythm pattern generating means 10 is selectively output in a time interval corresponding to each musical instrument.

30 receives the data read end signal from the data length switching MPX 28 and the on/off switching MP
A logical product is performed with the on/off signal by X29, and the output is supplied to the CS terminal of the waveform memory 3. In other words, the output is offset so as not to read unnecessary waveform data. In the above manner, the rhythm pattern generating means 1o shown in FIG. When the speed switching information is set and a reset signal is output to the reset terminal of the 13btt counter 18 shown in FIG. 7, the 13bit counter 18 is reset and starts counting up, and the operation of each circuit described above is Accordingly, only necessary pieces of waveform data among the plurality of waveform data are read out from the waveform memory 3 in a time-division manner.

Although the embodiment shows the case where the present invention is applied to a rhythm sound source, the present invention can be applied to any case where it is necessary to read out a plurality of musical sound waveforms at the same time.

As described above, the present invention can generate multiple tones at the same time by reading out data in a time-sharing manner using digital means. You don't need as many tones as you want, you just need to provide one for each, so you can use a large capacity one.
It is suitable for chip memory and can greatly reduce the number of parts. Moreover, since the present invention allows for tone color switching, readout speed switching, and data length switching, it is possible to achieve the very excellent effect of efficiently using the memory according to the musical sound waveform to be read out.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a conventional waveform readout device, FIG. 2 is a block diagram showing an entire embodiment of the present invention, and FIGS.
FIG. 6 is an explanatory diagram of time-division readout, FIG. 6 is a block diagram showing the address control means of the above embodiment, FIG. 7 is a circuit diagram showing the specific configuration of the address control means, and FIG.
Figure 4al e (b> is an explanatory diagram of the selection matrix, No. 9
The figure is a diagram showing the timing of data length switching. ' 3...Waveform memory, 4...D/A
Conversion circuit, 6°-7... Electroacoustic conversion device, 1
DESCRIPTION OF SYMBOLS 1... Address control means, 12...- Time division readout control means, 13... Readout address counter, 14... Readout speed switching means,
15... Tone color switching means, 16... Data length switching means, 17... On/off control means. Name of agent Patent attorney Toshi Nakao Haga 1 person 13
Figure 1 Figure 4 Figure 1, $2 tail 5 Figure 8 Figure 9 ty lρ2

Claims (3)

[Claims] (1) A waveform memory storing a plurality of pieces of musical waveform data, an address control means for controlling the readout address, and a time unit for reading out the plurality of musical tone waveform data in a time division manner in a plurality of corresponding time intervals. The plurality of waveform data can be read out by controlling the readout address of the waveform memory in a time-division manner, comprising a division readout control means and a means for converting the digital data from the waveform memory into an acoustic signal. An electronic musical instrument characterized in that arbitrary waveform data are read out substantially simultaneously. (2) The electronic musical instrument according to claim 1, wherein the address control means is provided with readout speed switching means to change the playback pitch or select a readout speed suitable for a musical sound waveform. 2,,- (3) In addition to providing a plurality of waveform data with different tones among the plurality of musical waveform data stored in the waveform memory,
The address control means is provided with a timbre switching means for switching between the plurality of waveform data having different tones, and arbitrary waveform data among the plurality of waveform data having different tones is switched and read in a predetermined time interval. An electronic musical instrument according to claim 1, characterized in that: