JPS62177597A - 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 in electronic musical instruments and the like. In particular, the present invention relates to a musical tone generator capable of producing a sound consisting of a part that depends on pitch frequency and a part that does not depend on pitch frequency.

(Summary of the Invention) The present invention is an 8r source (hereinafter referred to as overtones) used in electronic musical instruments, etc., in which the frequency and amplitude of a plurality of sine waves are independently set to arbitrary values, and a single musical tone is obtained by combining them. In the additive sound source), for each sine wave (hereinafter referred to as partial tone), it is possible to select whether or not to depend on the pitch frequency, which increases the expressive ability of music &.

(Prior art) When a harmonic addition sound source is used in a conventional electronic musical instrument,
The overtone additive sound source was used to create the basic timbre. The basic tone is set so that each partial has a predetermined frequency ratio and a predetermined amplitude of 1J, and when producing, all partials Δ have a frequency equal to the product of the pitch frequency and the frequency ratio. It was configured. In other words, all partials depended on pitch.

(Problems to be Solved by the Invention) When a conventional acoustic musical instrument produces a musical tone, the pitch is determined by the two vibration sound sources of the instrument.

Also, independent of pitch, there is a fixed frequency component that is always produced for any pitch.

When the frequencies of all partials depend on the pitch frequency, as in conventional harmonic addition, in order to reproduce the fixed frequency component, a different series of sound sources that are independent of the pitch are used in parallel, and they are produced at the same time. It was necessary to let them do so.

(Means for Solving the Problems) In order to eliminate such problems, the present invention uses overtone addition and source to increase the frequency by a predetermined multiplier of 4 or 4 for each partial tone. Or add a predetermined magnification to the fixed frequency.
A switch is provided to select whether to use the input frequency or not.

(Function) For each partial tone, a switch selects whether to set the frequency by a predetermined multiplier to the pitch frequency, or to set the frequency by multiplying the fixed frequency by a predetermined multiplier. It can be divided into dependent partials and non-dependent partials. Furthermore, the partials that do not depend on pitch are
Since the frequency and amplitude can be set for each partial, it is possible to arbitrarily create a composition of the fixed frequency components of the sound.

(Example) Hereinafter, an example of the present invention will be described in detail according to the drawings. FIG. 1 is a block diagram of a musical tone generator. The pitch setting means 1 sets a frequency of a logarithmic scale with two bases in the pitch frequency register 2. Data from the pitch frequency register 2 is inputted from series a to switch 3a of series n 3n. Series a to n are each 1
It consists of two partials. Items with a subscript are held separately by each series, and items without a subscript are used by all series on a time-sharing basis. The following explanation will be based on the a series as a representative.

The partial frequency register 4a stores the ratio of the partial to the fundamental frequency on a logarithmic scale with two bases. The data from the partial frequency register 4a is sent to the adder 5.
input to a.

When the switch 3a is ON, the data from the pitch frequency register 4a is input to the adder 5 via the switch 3a, and partial tones depending on the pitch frequency are formed after the adder DXer 5. Further, when the switch 3a is OFF, the data from the pitch frequency register 4a is cut off by the switch 3a, and zero is applied to the adder 5. In this case, data related to a fixed frequency that is output from the partial 8 frequency register 4a is output from the adder 5a, independent of the pitch frequency, and fixed frequency partials are formed from the adder ζ'5 unit 5 onwards. Ru. Since the data in the interval frequency register 2 and the r-ta in the partial frequency register are on a logarithmic scale, the data added by the adder F1 unit 5 also becomes a logarithmic scale. Logarithmic addition → corresponds to multiplication on a linear scale.

The output from the adder 5a becomes an input to the exponent converter 6. The exponent converter 6 has the function of converting the logarithmic scale data from the adder 5 into linear school data. A block diagram of the index converter 6 is shown in FIG. The logarithmic data is input to the input register 6X, the decimal part is read out from the "base 2 exponent" table 6Y, and only the decimal part is converted to leaf data and input to the shift circuit 6Z. The integer part of the input register 6X is input to the shift circuit 6z, and according to the value, the data from the exponent table 6Y is shifted to the left.

Return to Figure 1 again. Data converted from logarithmic data to linear data by the index 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 the exponent converter 6 enters the trimming register 7X. The data in the addition value register 7X and the accumulation register 7z.

It is filtered by the adder 7Y and returned to the cumulative n register 7Z. The value of the accumulation register 71 becomes the address of the sine wave table 8, and every time the accumulation register 7X overflows, the sine wave table 8 is restarted from the beginning.
Starts to yang. The output from the sine wave table 8 is a sine wave with the frequency of each partial.

Return to Figure 1 again. The amplitude counter 10a is a counter that manages the amplitude of the a series, which is multiplied by the data from the sine wave table 8 in the multiplier 9 (, added to other series in the adder 11, Musical tone and L from converter 12)
is output.

(Effects of the Invention) According to the present invention, there is a switch for selecting whether to output the frequency according to the pitch frequency or at a fixed frequency for each partial, so that only a part of the musical tone to be sounded can be output according to the pitch frequency. , the rest can be output at a fixed frequency. This makes it possible to mix pitch-independent partials with pitch-based instrumental sounds, such as percussion sounds.
It significantly increases the expressive ability of musical tones.

[Brief explanation of drawings]

Fig. 1 is a block diagram of the musical tone generator, Fig. 2 G,
1. Exponent converter configuration diagram; FIG. 3 is a pitch counter configuration diagram. 1... Pitch setting means 2... Pitch frequency register 3... Switch 4... Partial frequency register 5... Adder 6... Exponent converter 7... Pitch counter 8... Sine wave table 9... Rider 10... Amplitude counter 11... Adder 12... D/A converter ((l! 1?S) Output index converter configuration diagram P.I.
Figure 2 Figure 3

Claims (1)

[Scope of Claim] A musical tone generator capable of independently setting the frequency and amplitude of a plurality of sine waves to arbitrary values, comprising a register containing a frequency ratio of the plurality of sine waves, and further comprising a register containing a frequency ratio of the plurality of sine waves, and means for multiplying the frequency ratio by the pitch frequency for each of the plurality of sine waves, and for each of the plurality of sine waves, multiplying the pitch frequency by the frequency ratio and the pitch frequency. Equipped with a switch that allows you to select whether to input to the multiplying means or to input a fixed frequency instead of the pitch frequency, and the frequency of multiple sine waves can be multiplied by the frequency ratio of the pitch frequency or multiplied by the frequency ratio of the fixed frequency. A musical tone generating device characterized in that it is possible to select whether to generate a musical tone.