JP2626436B2 - Effect giving device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an effect imparting device for changing a tone of a musical tone to change a tone.

[0002]

2. Description of the Related Art A phaser has been conventionally proposed as an effect circuit for continuously changing the tone of a musical tone (Japanese Patent Laid-Open No. 62-187392). The phaser uses a phase shift circuit whose phase delay varies depending on the frequency.
By changing the parameters given to the phase shift circuit, the frequency-phase shift delay characteristic of the phase shift circuit is changed to change the tone.

[0003]

However, the conventional phaser only accepts a one-channel tone signal and outputs a one-channel signal. Therefore, even if the tone can be changed, the spatial extent is increased. There was a disadvantage that it could not be obtained.

[0004] It is an object of the present invention to provide an effect imparting device capable of giving a musical sound a spaciousness by using a plurality of channels.

[0005]

According to the present invention, in a phasor device in which a plurality of phase shift means are connected in series, a synthesizing means for synthesizing one or a plurality of signals output from the plurality of phase shift means. Are provided, and the output signals of the respective combining means are output signals of independent channels.

[0006]

In the effect applying apparatus of the present invention, a plurality of (first to n-th) phase shift means are connected in series. The input tone signal is supplied to first phase shift means. The phase shift means varies the amount of phase delay depending on the frequency. Therefore, the tone signal output from the phase shift means has a phase shifted from that before input. The tone signal is sequentially input to a plurality of phase shifting means connected in series. The tone signals output from the phase shifting means have different phases (phase shifts). These signals are distributed to a plurality of channels by a plurality of combining circuits. The tone signals of multiple channels have the same fundamental tone because the harmonic components are the same, but since the phases of the harmonic components are different, the tone is slightly different in nuance, and these are emitted from different channels. It is possible to form a musical tone with a feeling of expansion.

[0007]

FIG. 1 is a block diagram of an effect applying apparatus according to an embodiment of the present invention. This effect imparting device is a device which imparts a phasor effect to an externally input digital musical tone signal by an effect circuit, converts the signal into an analog signal, and outputs the analog signal from a sound system. The digital tone signal is input to the effect applying unit 1. The effect imparting section 1 imparts various effects to the digital musical tone signal. The digital tone signal to which the effect is given is converted by a D / A converter (DAC) 2 into an analog tone signal. The tone signal converted to analog is output to the sound system 3. The sound system 3 amplifies the tone signal and emits the sound from a speaker or the like. Further, a modulation signal generating section 4 is connected to the effect applying section 1. The modulation signal generating section 4 includes the effect imparting section 1
This is a circuit for generating a modulation signal to be input to the. The effect imparting unit 1 increases / decreases the effect imparting amount and the change speed by the modulation signal. Control elements such as a pedal and a modulation wheel are connected to the modulation signal generator 4.

FIG. 2 shows the effect imparting section 1. This circuit is a phasor effect circuit. Note that the effect imparting unit 1 is constituted by a DSP in an actual device, and this phasor circuit is also realized by a DSP and a microprogram for controlling the DSP.

In this circuit, a plurality of all-pass filters 2
0 to 24 are connected in series. The outputs of the second-stage and fourth-stage all-pass filters 21 and 23 are added and synthesized by an adder 29, and further added and synthesized with an input signal by an adder 30 and output. This signal becomes the left channel output. The outputs of the third-stage and fifth-stage all-pass filters 22 and 24 are added and synthesized by an adder 31, and further added and synthesized with an input signal by an adder 32 and output. This signal becomes the right channel output. As a result, the tone signals input as monaural signals have different phases.
It can be output as a channel signal, giving a sense of spaciousness of the musical sound.

The all-pass filter has the following structure. A description will be given taking the all-pass filter 20 as an example. The all-pass filter 20 includes a delay 41, adders 40 and 42 provided before and after the delay 41, and a coefficient multiplier 4
3, 44. The output of the adder 42 is input to the adder 40 on the input side of the delay 41 via the coefficient multiplier 44. The coefficient multiplier 44 multiplies the output by a coefficient (modulated signal). The adder 40 adds the input tone signal and the output of the coefficient multiplier 44 and provides the result to the delay 41, thereby causing a phase delay. Coefficient multiplier 43
Multiplies the input tone signal by a coefficient (modulation signal) given from the outside, and inputs the result to an adder 42 connected to the output side of the delay 41. In the adder 42, the output of the coefficient multiplier 43 is subtracted from the output of the delay 41. This makes the frequency characteristics flat. Although the phase delay increases as the frequency increases as shown in FIG. 3, the degree is controlled by the coefficient input to the coefficient multiplier 43.

The outputs of the all-pass filters 21 to 24 are multiplied by predetermined coefficients by coefficient multipliers 25 to 28 and then added and synthesized to the left and right channels. Can be changed, and the feeling of spreading can be changed.

FIG. 4 is a diagram showing a configuration of the modulation signal generator 4. The selector 54 is connected to the LFO 50, the envelope extraction unit 51, and the control operator 52. The control operator 52 is connected to a selector 54 via a coefficient multiplier 53. The selector 54 is connected to a fourth power circuit 55. The fourth power circuit 55 is a circuit for raising the input data to the fourth power. The data output from the fourth power circuit 55 is output as a modulation signal via an inverter 56 and an adder 58.

The envelope extracting section 51 is a circuit for extracting and outputting the envelope of the input tone signal.
The controller 52 includes a pedal, a modulation wheel, and the like, and outputs operation amount data when operated by a player during a performance. The manipulated variable data is supplied to the coefficient multiplier 53.
Is input to The coefficient multiplier 53 multiplies the manipulated variable data by a predetermined coefficient and inputs the data to the selector 54. On the other hand, L
The FO 50 is an oscillation circuit that generates a triangular wave, and its frequency and amplitude (depth) are determined by input parameters. The LFO 50, the envelope extraction unit 51, and the coefficient multiplier 53 output data normalized to 0 ≦ x ≦ 1 (x: output of each unit).

A selector 54 to which these data are input
Inputs any one of the triangular wave of the LFO 50, the envelope signal extracted by the envelope extraction unit 51, or the operation amount data of the controller 52 to the fourth power circuit 55 based on the select signal.

The select signal outputs these data in a time-division manner. The above-described effect imparting unit 1 outputs this data (adder 5
8), and allocates and inputs to each coefficient multiplier in a time-division manner.

The fourth power circuit 55 has two multipliers connected in series. Each multiplier squares the input signal.
This is repeated twice to obtain the fourth power. By quadrupling the input signal, a linear change is approximately converted into an exponential change. The listener's perception of changes in frequency, volume, etc., is logarithmic. That is, the higher the frequency and the higher the volume, the less the sense of change. Therefore, in order to linearly change the frequency and the volume in an audible manner, it is necessary to change these exponentially. Therefore, an exponential function is approximated and converted by a fourth power circuit.

The inverter 56 is a circuit for inverting the data raised to the fourth power. The adder 57 is a circuit that shifts the inverted data by plus (1 × BIAS).

It should be noted that the adder 5 depends on the output destination of the modulated signal.
8, the shift amount is different, so the shift amount is determined based on the output destination of the modulation signal. Further, since the waveform to be used differs depending on the output destination of the modulation signal, the inverter 56
Is determined based on the output destination of the modulation signal.

The above-mentioned fourth power circuit 55 is a circuit for calculating y = x ⁴ (where x: input data, y: output data). As shown in FIG. 5, the y = x ⁴ curve is 0. ≦ x ≦
In section ^{1, the} curve approximates to a y = 55.3 ^x-1 curve.
Therefore, a linear function change can be converted into an exponential function change by performing the fourth power operation. For example, a linear triangular wave output from the LFO 50 can be converted into a waveform obtained by combining exponential function curves as shown in the upper part of FIG.

Although y = x ⁴ is used as a function approximating the exponential function in the above embodiment, the function to be used is not limited to this. It is also possible to approximate in a section other than 0 ≦ x ≦ 1.

In the above embodiment, the phase circuits assigned to the left and right channels are fixed (the phase circuits 21 and 23 are assigned to the left channel, and the phase circuits 2 and 23 are assigned to the right channel).
2, 24), as shown in FIG. 6, inputting the output signals of all the phase circuits to a selection unit capable of arbitrarily changing the combination,
The assignment may be made to the left and right channels based on selection instruction data generated in response to the selection instruction by the operator. Further, the number of channels is not limited to two channels on the left and right.

[0022]

As described above, according to the present invention, a monaural tone signal can be output as a tone signal of a plurality of channels by dividing and outputting the outputs of the plurality of phase shift circuits to a plurality of channels. The spread of the musical sound can be obtained.

[Brief description of the drawings]

FIG. 1 is a block diagram of an effect providing apparatus according to an embodiment of the present invention.

FIG. 2 is an effect imparting section (phasor circuit) of the effect imparting circuit.
Figure showing

FIG. 3 is a diagram showing a phase change of a phase shift circuit used in the phasor circuit;

FIG. 4 is a detailed block diagram of a modulation signal generator of the effect applying device.

FIG. 5 is a diagram showing output characteristics of a fourth power circuit used in the modulation signal generation unit.

FIG. 6 is a diagram showing another embodiment of the phasor circuit.

[Explanation of symbols]

 1-Effect giving section 20-24-All-pass filter (phase shift circuit)

Claims (1)

(57) [Claims] 1. A phasor device in which a plurality of phase shifting means are connected in series, a plurality of combining means for combining one or a plurality of signals output from the plurality of phase shifting means are provided, and each combining means is provided. Wherein the output signals are output signals of independent channels.