JPS62144198A - Musical sound generator - 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 [Field of Industrial Application] The present invention relates to a musical tone generator used as a sound source for electronic musical instruments and the like. In particular, the present invention relates to a musical tone generator capable of periodically changing frequency.

(Summary of the Invention) The present invention is used in electronic musical instruments, etc., in which the frequencies and amplitudes of a plurality of sine waves are arbitrarily determined, and a sound source (hereinafter referred to as an overtone addition sound source) that obtains one musical tone by combining the frequencies and amplitudes of a plurality of sine waves. By making it possible to select whether or not to vary the frequency periodically (hereinafter referred to as vibrato) for each sine wave (hereinafter referred to as partial tone), the ability to express musical tones can be significantly increased.

[Conventional technology]

In conventional electronic musical instruments, the way to create vibrato is to modulate the basic clock connected to all sound sources at low frequency and speed it up or slow it down, so that all sound sources are at the same speed and
They had the same depth of vibrato. In this case, you can apply several triggers at the same time and play sounds of different pitches. Even if it is an island, the same vibrato will be applied to all sounds in the same phase.

Furthermore, with recent digital sound sources, it is now possible to apply vibrato to each sound produced by a single trigger. In this case, the multiple overtones that constitute the musical tone will be affected by vibrato at the same speed and depth.

[Problem that the invention seeks to solve]

When the same vibrato is applied to a plurality of pitches as in the conventional example described above, the naturalness of an ensemble performance is not created, and the problem of mechanical confusion arises. Even when each note had an independent vibrato, the tone was monotonous, so it was necessary to prepare a separate series without vibrato and add it together to obtain an effect called chorus. (Hereinafter referred to as chorus effect) [Means for solving the problem] In order to solve the above problem, the present invention uses a harmonic addition type sound source that independently manipulates the amplitude and frequency of the harmonic, and further, By providing a switch for each partial tone to select whether or not to apply vibrato, a chorus effect can be obtained between the partial tones, and a natural ensemble platform can be obtained during ensemble performance.

[Effect]

By providing a switch for each partial, and performing the vibrato 0N10FF system ('fl) independently for each partial,
A low frequency modulation signal is applied only to the partial tone whose switch is turned on.

〔Example〕

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a block diagram of a musical tone generator.

The vibrato counter 1 is a counter for repeatedly scanning the waveform stored in the vibrato waveform table 2. The counter value is vibrato waveform table 2
The address will be The vibrato counter 1 has a configuration as shown in FIG. The vibrato counter consists of an accumulation register IX, an added value register IZ, and an adder IY that adds the values of the added value register IZ. The data in the accumulation register IX becomes the input to the vibrato waveform table 2 in FIG. Accumulation register IX scans the vibrato waveform table again from the beginning due to overflow. Further, the addition value register IZ is a register that determines how many addresses of the vibrato waveform table are to be skipped when scanning. Since the vibrato counter 1 operates with the same clock, when the value of the addition value register IZ is large, the scanning speed of the vibrato waveform table is fast, and when it is small, the scanning speed of the vibrato waveform table is slow.

Returning to Figure 1 again. The output from the vibrato waveform table 2 enters the switches 3a to 3n. The output from the vibrato waveform table 2 is data on a logarithmic scale obtained by multiplying the frequency by a logarithm.

In FIG. 1, n series from the first partial to the nth partial are shown in a plane, but each series is processed in a time-division manner. The following will explain series a as a representative.

The pitch register 4a contains data for creating the reference frequency of series a in the form of logarithmically transformed frequencies. The switch 3a is an 'MtR switch which passes or does not pass the data of the vibrato waveform table 2 and gives zero to the adder.

When the switch +3a is selected to be conductive (ON state), the adder 5 adds the data in the pitch register 4a and the data from the switch 3a.

Addition on a logarithm is equivalent to multiplication on a linear scale.

The logarithmic data from the addition 35 is converted to a linear scale by a linear converter 6. Namely, Zhou.

Data that is proportional to the wave number is generated here.

The configuration of the linear converter is shown in FIG. Logarithmic data is input to the input register 6X, the decimal part thereof is used as an address, and y-y of the exponent table 6Y with a base of 2 is read. The data is shifted to the left by the shift circuit 6Z the number of times indicated by the integer part of the input register 6X.

Return to Figure 1 again. The output from the linear converter 6 is input to the pitch counter 7a. The pitch counter 7a is a counter for scanning sine waves stored in the sine wave table 8. FIG. 3 shows the configuration of the pitch counter 7a. Data from linear converter 6 enters addition value register 7Z.

The data in the addition value register 7Z and the accumulation register 7X are added by the adder 7Y and returned to the accumulation register 7X again. The value of the accumulation register 7X becomes the address of the sine wave table 8, and each time the accumulation register 7X overflows, it starts scanning the sine wave table 8 again from the beginning.

Return to Figure 1 again. The sine wave table 8 addressed by the pitch counter 7a outputs sine wave data corresponding to each address.

The amplitude counter 10a is a counter that manages the a-series amplitude data. The amplitude output of the amplitude counter 10a and the frequency output of the sine wave table 8 are multiplied by a multiplier 9, and added to signals of other series by an adder 11. The digital output signal of the adder 11 is converted into an analog signal by a D/A converter 12 and output.

In the embodiment of FIG. 1, one sequence is responsible for the generation of a partial. Pitch counters 7a-7n control the frequency of each partial, and amplitude counters 10a-Ion relate to the amplitude of each partial. By selecting whether to open or close the switches 3a to 3n, it is determined whether or not the vibrato I data from the vibrato waveform table 2 is reflected in each partial tone.

The output of each series before entering the adder 11 in FIG. 1 is digital, but FIG. 5 shows a diagram in which the amount is expressed as an analog IQ)7-. In FIG. 5, the series a to d are schematically shown. The horizontal axis is time, and the vertical axis is frequency on a linear scale. Set the center frequency to 10011z for series a, 20011z for series 2, 30011z for c, and 400H for d.
It is set as z. The switch 3a is shown in an open state, that is, a non-conducting state, the switches 3b and 3C are shown in a closed state, that is, a conducting state, and the switch 3d is shown in an open state. Note that this is a schematic diagram when the data of the vibrato waveform table 2 is a substantially sine wave. In such a case, from 10011z to 400l
The harmonics up to lz are the first to fourth harmonics, respectively. The 1st and 4th harmonics are not affected by vibrato, and the 2nd harmonic is
Vibrato will be applied to the overtones and the third overtone.

FIG. 6 is also the same as FIG. 5, but with different settings. 100Hz for series a and b, 20Hz for series C1d
The switch has a center frequency of 011z and shows an open state in series a and c and a closed state in series b and d. In this case, series a and b indicate a chorus effect, and series A and D indicate a chorus effect.

〔Effect of the invention〕

According to the present invention, there is a switch for whether or not to apply vibrato for each G note that is produced by one trigger.
■You can select partials of a sound and apply vibrato, and you can also get a chorus effect between partials. Also, by applying vibrato to some partials of the l-tone,
Unlike conventional vibrato, which has a softer vibrato and is mechanically uniform, it can produce a natural vibrato effect.

[Brief explanation of drawings]

FIG. 1 is a block diagram of the musical tone generator, FIG. 2 is a configuration diagram of a vibrato counter, FIG. 3 is a configuration diagram of a pitch counter T75, and FIG. 4 is a configuration diagram of a linear converter. FIG. 5 shows a diagram of frequency changes over time. FIG. 6 shows a frequency change diagram over time showing the chorus effect. 1... Vibrato counter 2... Vibrato waveform table 3... Switch 4... Pitch register 5... Adder 6... Linear converter 7... Pitch counter 8... Sine wave table 9... Multiplier 10... (Tatsuwabi Kaunota 11... Adder 12... D/A converter and above Time change Ahi group funeral of the circumference t of each thread row 5 Menkura b Figure

Claims (1)

[Scope of Claims] A musical tone generator capable of independently setting the frequency and amplitude of a plurality of sine waves constituting a musical tone to arbitrary values, comprising: a frequency modulation signal generation means; and an output of the frequency modulation signal generation means. connected to the terminal,
a plurality of switches provided corresponding to the plurality of sine waves forming the musical tone; one input terminal being connected to the output terminal of each of the plurality of switches, and the other input terminal being connected to the plurality of sine waves forming the musical tone; and an adder connected to a sine wave, and wherein conduction or non-conduction of the plurality of switches can be arbitrarily selected.