JP3118863B2 - Musical tone generator using scale detection device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION In each of the embodiments of the present invention, a pitch is extracted by inputting a musical instrument sound, a human voice, or the like, and the scale is determined whether or not the extracted pitch is a pitch of a desired scale. Detects the scale and level of the scaled tone that has been determined, and generates a musical tone by generating a scale tone or changing the tone to be generated in accordance with the range or level. The present invention relates to a musical sound generation device using a scale detection device.

[0002]

2. Description of the Related Art Conventionally, pitches are extracted by inputting musical instrument sounds or human voice sounds and the like, a scale determination is performed, and the results are printed out in the form of a musical score or a series of determination results are coded and recorded. After that, a technique of outputting as another musical instrument sound and performing automatically is proposed (JP-A-57-692).
No. JP-A-58-97179).

[0003] However, in such a conventional technique, it is basically possible to cope only with a single tone input, and no consideration has been given to a double tone (including a chord) input.

Therefore, it has been proposed to detect a chord name in response to a chord input and display a chord name in accordance with the chord name signal (Japanese Utility Model Application Laid-Open No. 60-26091).

[0005] However, the one disclosed in this publication discloses an analog band-pass filter circuit for the number of musical scales, a peak hold of each output, and a level detection circuit for constructing a chord from a peak having a large peak. It is a candidate for sound.

According to the technique using such an analog filter, the judgment result fluctuates due to the influence of the external temperature,
There is a problem that it is not stable, and there is also a disadvantage that the circuit configuration becomes large-scale and large.

Therefore, the applicant of the present invention first detects the scale of the sound in a short time whether the input sound signal is a single sound or a double sound, and furthermore, the circuit scale is small. (Japanese Patent Application No. 2-12).
No. 3789).

The scale detecting device basically includes a storage means for sequentially storing digital waveform signals representing a given acoustic signal, and a digital waveform signal stored in the storage means for each scale. Digital signal processing means for sequentially performing digital filtering of different characteristics in a time-division manner to detect the level of a frequency spectrum relating to a corresponding frequency; and the digital signal processing means based on a result of the digital filtering performed by the digital signal processing means. Detecting means for detecting one or a plurality of chromatic sounds included in the acoustic signal to be obtained, wherein the electronic musical instrument using the chromatic sound detecting device includes, in addition to the above-described means, one to four detected by the detecting means. Musical tone signal generating means for generating a musical tone signal corresponding to a plurality of scale tones with a predetermined tone color.

[0009] Therefore, according to the scale detecting device filed by the applicant of the present invention, all signal processing can be digitally processed, and whether the input acoustic signal is a single tone or a double tone is obtained. The sound scale of the sound can be detected in a short time, and the circuit can be operated stably on a small scale.

[0010]

However, in the scale detecting device and the electronic musical instrument using the same which the applicant of the present invention has applied, first, the scale detecting device converts the level of the frequency spectrum into digital signal processing means. When the envelope value is equal to or greater than a predetermined reference value according to the digital filtering processing result, the chromatic note is detected as a chromatic note, and the detected chromatic note is currently assigned as the chromatic note for pronunciation. When the scale tone is detected, when the scale tone is detected, it is assigned as a scale tone for pronunciation, and each scale tone assigned as the scale tone for pronunciation is produced by the musical tone signal generating means in a single tone, and When the scale note assigned as the scale note is no longer detected, it is deleted from the scale note for pronunciation,
Since the generation of the musical tone corresponding to the deleted scale tone is stopped, there is a problem that data of any part in any range is sounded with exactly the same timbre and lacks in musicality.

That is, music usually includes various parts,
For example, it is divided into parts such as accompaniment and melody, and the sounds of these parts are compositely overlapped and played as music.

However, in the scale detecting device filed by the applicant of the present invention, when a scale different from the scale tone currently assigned as the scale tone for pronunciation is detected, the scale tone is assigned as the scale tone for pronunciation. However, since the tone is generated with a constant tone, the scale tone of each part is pronounced with the exact same tone, and there is a problem that the musicality is lacking.

Therefore, the inventions of the present application perform time-division digital filtering processing of an input acoustic signal to detect scale sounds, determine the detected scale sounds, perform level detection, and perform level detection. By specifying the timbre based on the reference range and the level, and making the scale tone not be emitted, it is possible to perform a musically rich performance, and to extract the scale tone of a predetermined part. It is intended to give a so-called minus one effect to give a musicality different from the input audio signal.

[0014]

According to the first aspect of the present invention,
The sound signal is analyzed by the scale detecting device, the scale sound included in the sound signal is detected, and the detected scale sound is applied to a musical tone generating device that emits a predetermined tone color. Digital signal processing means for sequentially performing digital filtering processing of different characteristics in a time-division manner to detect a level of a frequency spectrum related to a frequency corresponding to each scale; and a digital filtering processing result obtained by the digital signal processing means. A scale detecting means for detecting one or a plurality of scale sounds included in the sound signal; and a range discriminating means for determining whether or not the scale sound detected by the scale detecting means is within a predetermined reference range. Means for comparing each scale tone of each range determined by the range determining means with a predetermined reference level. A tone detecting means, a musical tone generating means for generating an input scale tone by a predetermined tone, and a tone scale of a detected tone scale based on a tone range determination result of the tone range determining means and a level detection result of the level detecting means. And control means for providing predetermined tone color data and outputting to the musical tone generating means according to the level of the scale tone.

For example, as set forth in claim 2, the control means includes, among the scale sounds detected by the scale detection means, those other than the scale note having the predetermined reference level or higher within the predetermined reference range. It may output only a chromatic note to the musical tone generating means as a chromatic note for pronunciation, and as described in claim 3, among the chromatic notes detected by the chromatic note detecting means, For chromatic tones that are equal to or higher than the predetermined reference level within a predetermined reference range, output to the musical tone generating means together with predetermined timbre data, and for chromatic tones other than chromatic tones equal to or higher than the predetermined reference level within the predetermined reference range. Alternatively, it may be output to the musical tone generating means together with tone color data other than tone color data assigned to the scale tone.

Further, the musical sound generating device may be, for example,
As described in the above, the range determining means determines whether there is a scale tone detected by the scale detecting means within a plurality of preset reference range, and the level detecting means, For each scale tone determined by the determination means, a plurality of reference levels are compared, and a comparison result for each reference level is output to the control means.
A predetermined tone color data is assigned to each of the scale sounds detected by the scale detecting means based on the determination result of the tone range determining means and the level detection result of the level detecting means, for each of the plurality of reference ranges and the plurality of reference levels. Output to the musical tone generating means.

Further, the digital signal processing means includes:
For example, as described in claim 5, bandpass filtering processing in which a frequency corresponding to each of the scales is set as a center frequency is sequentially executed in a time-division manner.
As described in the above, a signal for executing band-pass filtering processing with a frequency corresponding to each scale as a center frequency sequentially in time division and extracting an envelope from a waveform signal obtained as a result of the band-pass filtering processing By sequentially performing processing operations, the level of a frequency spectrum related to the frequency corresponding to each of the scales may be detected, and a high-pass filtering process having a predetermined characteristic may be performed as described in claim 7. 9. A low-pass filtering process in which a resonance having a peak at a frequency corresponding to each scale is added and the low-pass filtering process is sequentially performed in a time-division manner.
As described in, a high-pass filtering process having a predetermined characteristic is performed, and a low-pass filtering process in which resonance having a peak is added at a frequency corresponding to each scale is sequentially executed in a time-division manner. A signal processing operation for extracting an envelope from a waveform signal obtained as a result of the filtering process may be sequentially performed to detect a level of a frequency spectrum related to a frequency corresponding to each scale.

[0018]

According to the first aspect of the present invention, an acoustic signal generated from a musical instrument such as a piano or an electronic musical instrument is digitally converted and input to digital signal processing means. The digital signal processing means detects a frequency spectrum level related to a frequency corresponding to each scale by sequentially performing time-division digital filtering processing of different characteristics on the digital waveform signal as the acoustic signal,
Output to scale detecting means. The scale detecting means detects one or a plurality of scale sounds contained in the sound signal based on a result of the digital filtering performed by the digital signal processing means. The scale sound detected by the scale detecting means is compared with a predetermined reference range which is set in advance by the range determining means to determine which range the scale sound is.
Each scale sound whose range is determined by the range determining means is compared with a preset reference level by the level detecting means, and the level of each scale sound is detected. The control means controls the output of the scale tone for which the range determination and the level detection have been performed to the musical sound generating means. That is, the control means assigns timbre data based on the gamut and level of the scale sound detected by the scale detection means based on the gamut discrimination result and the level detection result, and outputs the timbre data to the musical tone generation means together with the timbre data.
The musical sound generating means generates the inputted scale sound with a designated tone color.

Therefore, the inputted acoustic signal is subjected to digital filtering processing, and the scale note detected by the scale is located in any preset reference range where the scale note is set in advance.
In addition, it is possible to produce a tone with different timbres depending on the chromatic tone of the level, thereby performing a musically rich performance.

According to the second aspect of the present invention, the control means, among the scale sounds detected by the scale detection means, only the scale sounds other than the scale sounds having a predetermined reference level or higher within a predetermined reference range. It is output to musical tone generating means as a musical scale tone.

Therefore, it is possible to prevent the generation of a scale tone higher than the predetermined reference level within the predetermined reference range, and to exert a so-called minus one effect.

According to the third aspect of the present invention, the control signal is provided for a predetermined scale within a predetermined reference range, among the scale sounds detected by the scale detection means. The musical tone data is output to the musical tone generating means together with the timbre data. For chromatic tones other than chromatic tones of a predetermined reference level or higher within the predetermined reference gamut, the musical tone generating means is output together with timbre data other than the timbre data assigned to the chromatic sounds. Output to

Therefore, the inputted acoustic signal is subjected to digital filtering processing, and the scale note detected by the scale is generated by using different timbres of a scale sound exceeding a predetermined reference level in a predetermined reference range and other scale sounds. And a more musically rich performance can be performed.

According to the fourth aspect of the present invention, the range determining means determines whether or not the scale sound detected by the scale detecting means is within a range of a plurality of preset reference ranges. The detecting means compares each scale sound determined by the range determining means with a plurality of reference levels, and outputs a comparison result for each reference level to the control means. Based on the discrimination result of the tone range discriminating means and the level detection result of the level detecting means, the control means decomposes each scale sound detected by the scale detecting means into the plurality of reference ranges and the plurality of reference levels. Predetermined tone color data is assigned and output to the musical tone generating means.

Therefore, the input acoustic signal is subjected to digital filtering processing, and the scale sounds detected on the scale are classified based on a plurality of ranges, and are classified based on a plurality of levels to give different timbres. And different tones depending on the level. As a result, sounds of different parts can be pronounced as sounds of different timbres, and a more musical performance can be performed.

According to a fifth aspect of the present invention, the digital signal processing means sequentially executes band-pass filtering processing using a frequency corresponding to each of the scales as a center frequency in a time-division manner. By sequentially performing time-division band-pass filtering processing with a frequency corresponding to each scale as a center frequency, and sequentially performing signal processing operations for extracting an envelope from a waveform signal obtained as a result of the band-pass filtering processing,
The level of the frequency spectrum related to the frequency corresponding to each scale is detected. According to a seventh aspect of the present invention, the digital signal processing means performs a high-pass filtering process having a predetermined characteristic and sequentially performs a low-pass filtering process to which a resonance having a peak at a frequency corresponding to each scale is added in a time-division manner. Running,
The invention according to claim 8 performs a high-pass filtering process of a predetermined characteristic, and sequentially executes a low-pass filtering process in which resonance having a peak is added at a frequency corresponding to each scale in a time-division manner. By sequentially performing a signal processing operation for extracting an envelope from a waveform signal obtained as a result of the filtering process, a level of a frequency spectrum related to a frequency corresponding to each of the above-mentioned musical scales is detected.

Therefore, according to the present invention, all signal processing can be performed in the digital domain, and high-speed and efficient scale extraction processing can be performed.

[0028]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of each invention of the present application will be described below. <Basic Principle> First, the basic principle of digital filter processing used in the embodiment will be described. In the embodiment, the digital filter processing is performed by a DSP (Digital Signal Processing).
r: Digital signal processor). That is, a program and data necessary for operating the digital filter as a digital filter are written in the DSP, a band pass filter H _t (z) as shown in FIG. 1 is formed, and an envelope extracting circuit is further formed to perform digital filtering and processing. Performs envelope extraction processing.

In FIG. 1, as an input signal X (n), a value obtained by sampling an analog sound signal at a predetermined sampling timing is converted into a digital signal (if it is originally supplied as a digital signal, it may be used as it is) and input. The input signal X (n) is subjected to filtering processing of n band-pass filters H _t (z) by DSP time division processing. In this filtering process, the transfer functions of the n bandpass filters H _t (z) are changed depending on the scales of a plurality of octaves.

[0030] Figure 2 shows the magnitude of the frequency characteristic in the case of adopting those Chebishiefu shaped as a band-pass filter H _t (z). The transfer function in this case is as follows, where t is a suffix (subscript) designating each scale.

(Equation 1) Here, if this bandpass filter _Ht (z) is configured with i = 1, the processing of the DSP is as follows.

(Equation 2) Will be executed. When i ≧ 2, the same calculation as the above expression is repeatedly executed. Further, the coefficients of each bandpass filter _Ht (z) can be obtained by numerical calculation.

As a specific example, when a band-pass filter of A ₄ = 440 Hz is configured under the following conditions (see FIG. 2), digital filtering of a transfer function having the following coefficient values is executed. . That is, under the condition of = 1 dB = (sampling frequency f _s ) = 10 KHz = 12 dB or more = 415 Hz = 430 Hz = 450 Hz = 466 Hz, the respective coefficients of the two-stage digital filter of i = 1 and 2 are as follows. H440Hz (0) = 0.08192384 For i = 1, a ₁ (1) = − 1.91442200776 a ₂ (1) = 0.9933673 b ₁ (1) = − 1.91105345727 b ₂ (1) = 1. For i = 2, a ₁ (2) = − 1.9210712 a ₂ (2) = 0.993606 b ₁ (2) = − 1.93525314797 b ₂ (2) = 1. Thus, the calculation of the band-pass filter H _t (z) is performed for each scale. It is executed in a time-sharing manner, and as a result, the signals Y _t (n), t
= 1 to N are obtained.

Next, DS is added to the result signal Y _t (n).
P performs the envelope extraction processing in a time-sharing manner. This envelope processing is performed by obtaining a peak level (absolute value) at predetermined time intervals (for example, for each frequency corresponding to each scale) with respect to the waveform of each result signal Y _t (n). Alternatively, a specific digital filter as described later is | Y _t (n) |
(The absolute value signal of Y _t (n)).

As described above, by the time division processing of the DSP, the envelope signals E _t (n),
t = 1 to N are obtained, and the CPU (microcomputer or the like) of the tone generator or the like to which the DSP is applied performs a level judgment on the output to obtain the original input signal X (n). One or more scale signals included in the waveform can be detected.

[0034] Thus, the basic principle is a band-pass filter H _t (z) having a peak for each chromatic is performed by time division filtering process, band-pass filter H _t (z) is above The present invention is not limited to the Chebyshev-type band-pass filter described above, and various functions can be realized by various types of digital filters. Further, the band-pass filter can also be realized by cascading a low-pass filter and a high-pass filter.

In the above-mentioned Chebyshev-type band-pass filter, in which A ₄ = 440 Hz, eight multiplications are required. Therefore, one improvement principle of the filtering process which reduces the number of multiplications when performing the filter operation and facilitates the real-time filtering will be described below.

<Improvement Principle> FIG. 3 shows an improvement principle of causing a DSP to perform a digital filter operation with a reduced number of multiplications. This bandpass filter includes a high-pass filter H ₁ (z) and a low-pass filter H _2t. is composed of (z) and a low pass filter H _E (z). In this bandpass filter, an input audio signal X (n) expressed in digital form is used.
The first input to the high-pass filter H1 (z), the high-pass filter H1 (z) is the details of which will be described later, the frequency 0 0 a high-pass digital filter with a maximum at a frequency f _s / 2.

The output Y (n) of the high-pass filter H ₁ (z)
Is a low-pass filter H _{2t that} operates time-divisionally for each scale t
(z), the low-pass filter H _2t (z) has the characteristics of a resonance-type low-pass digital filter having a peak at the scale frequency, as will be described in detail later.

Therefore, the high-pass filter H ₁ (z)
The magnitude of the frequency characteristic of the digital filter obtained by cascading the filter and the low-pass filter H _2t (z) is shown in FIG.
, Which is a pseudo bandpass filter.

In FIG. 4, f ₁ , f ₂ ,..., F _N correspond to the respective scale frequencies, and N can be set to about 40 to 50 (3 octaves to 4 octaves). In addition,
The scale detection in a wider octave range than this can be achieved by employing a high-speed DSP or a parallel processing by a plurality of DSPs.

The output W of the low-pass filter H _2t (z)
_t (n), _t = _1~N is given to the low-pass filter H _E (z) in a time sharing operation for each scale, the low-pass filter H
_Although the characteristics of _E (z) will be described later, this low-pass filter H _E (z)
Each output E _t (n) becomes an envelope signal for each musical scale, as in FIG. Subsequent processing is the same as in the case of the basic principle.

Next, the configuration and characteristics of each digital filter shown in FIG. 3 will be described in detail. High Pass Filter H ₁ (z) FIG. 5 shows a configuration example of the high pass filter H ₁ (z). This high-pass filter H ₁ (z) has a second-order FIR (Fi
nite Impulse Response) Digital filter
Its transfer function is

(Equation 3) It is. In FIG. 5, 5-1 and 5-2 are delay elements,
-3, 5-4, and 5-5 indicate multipliers, and 5-6 and 5-7 indicate adders. This high-pass filter H ₁ (z) is
When it is realized by calculation in

(Equation 4) Will be executed. In this case, the multiplication of the coefficient and the signal can be realized by simple shift processing.

The frequency characteristics of the high-pass filter H ₁ (z) are as follows:

(Equation 5) Ω = 0 (0 Hz) as shown in FIG.
In minimum, taking _{Ω = π (f s / 2Hz} ) becomes maximum in characteristics.

The low pass filter H _2t (z) Figure 7 shows an example of the configuration of a low pass filter H _2t (z). This low-pass filter H _2t (z) has a second-order IIR
(Infinite Impulse Response) Digital filter whose transfer function is

(Equation 6) It is.

As will be described later, the low-pass filter H _2t (z) changes θ and CY depending on the suffix t indicating the musical scale, and r is a parameter indicating the intensity of resonance (degree of peak). .

In FIG. 7, 7-1 and 7-2 are delay elements, 7-3, 7-4 and 7-5 are multipliers, and 7-6 and 7-7.
Indicates an adder. This low-pass filter H _2t (z)
Is realized by a DSP, W _t (n) = CY · Y (n) + 2r cos θW _t (n−1) −r ² W _t (n−2) (Equation (2)) Become. This low-pass filter H _2t (z)
The frequency characteristic of

(Equation 7) Given by Where the poles of this transfer function are

(Equation 8) , There is a double zero at Z = 0. FIG. 8 shows the arrangement of the poles and zeros of the transfer function, and the pole vector and the zero vector when θ is set to 0 <θ <π / 2. As can be seen from FIG. 8, as Ω moves along the unit circle from Ω = 0 to Ω = π, the length of the vector v ₂ initially decreases and then increases. Minimum vector v ₂
The length of

[Outside 1] Is near. Here, the magnitude of the frequency response at the frequency Ω is the ratio of the lengths of the zero-point vector v ₁ and the vector v ₂ , and the phase of the frequency response is formed by the vector v ₂ from the angle between the real axis and the vector v _1. It is known that the value is obtained by subtracting the angle, and FIG. 9 shows only the amplitude characteristic.

That is, as can be seen from FIG. 9, the magnitude of the frequency response (amplitude characteristic) is proportional to the reciprocal of the magnitude of the pole vector v ₂ and becomes maximum at Ω close to θ. And r
The sharpness of this peak is determined in accordance with the magnitude of, and a filter having a sharp peak (resonance characteristic) can be realized as r approaches 1.

As is apparent from the above description, each scale, be determined value of _{θ (θ = 2πf t / f} s), as shown in FIG. 10, resonance with peaks at scale frequency f _t , A low-pass filter H _2t (z) can be realized.

Note that r is set to a size that does not affect the level of the next scale, and CY is set to a size such that an output W ₁ (n) of the same level is obtained for each scale. Or it can be obtained mathematically.

For example, the scale frequency (f _t ) of f and Δf
Scale frequency f + Δf next to (ie, f _{t + 1} )
And the ratio of the magnitude of the frequency response to m: 1,

(Equation 9) By solving a quartic equation for r, one that satisfies 0 <r <1 is selected, and each coefficient −2rcos θ, r ² can be obtained. Now, as a result of numerical calculation, for example,
f _s = 5 KHz, with f = 440 Hz, When m = 4, -2rcosθ = -1.9773, r 2 = 0.9851, CY = 36.
It becomes 7. The same applies to other scales.

The low-pass filter HE (z) Figure 11 shows an example of a structure of a low-pass filter H _E (z). This is a second-order IIR digital filter having the same form as the low-pass filter H _2t (z) described earlier, and the transfer function is

[Equation 10] It is. This is obtained by _setting r = 0.9 and θ = 0 in the transfer function of the low-pass filter H _2t (z).

In FIG. 11, reference numeral 11-1 denotes an absolute value circuit for converting an input signal (output signal of the low-pass filter H _2t (z)) W _t (n) into an absolute value, and the output | W _t (n) ) | Is digitally filtered. 11-2 and 11-3 are delay elements,
11-4, 11-5, and 11-6 indicate multipliers, and 11-7 and 11-8 indicate adders. This low-pass filter H _2t (z) is set to D
When realized by operation in the _{SP, E t (n) = CE} | performing + 1.8Et (n-1) -0.81E t (n-2) ...... equation _{(3) | W t (n} ) Becomes

The low-pass filter H _2t (z) is a low-pass filter with resonance having a frequency characteristic having a peak at θ = 0, as described above, and has a characteristic (amplitude characteristic) shown in FIG. Take). Here, the coefficient CE is
It is a factor that makes the level of each musical scale uniform, and can be obtained as appropriate through experiments or the like.

FIG. 13 schematically shows an embedding signal E _t (n) obtained by the configuration of FIG. Thus, the low-pass filter H _2t (z) is connected to the absolute value circuit 11−
1, all the negative peak values (broken lines in FIG. 11) are converted to positive peak values and then subjected to a low-pass filter, so that the DC component of the waveform signal | W _t (n) | The operation is performed by the filter circuit.

<Overall Configuration of Embodiment> Next, a specific configuration of an embodiment of a musical tone generating apparatus using the musical scale detecting device according to the present invention will be described. FIG. 14 is an overall block diagram of a musical sound generating device 1 to which a musical sound generating device using the musical scale detecting device of each invention of the present application is applied.

The tone generator 1 has a CPU (Central Proc).
essing Unit) 2, ROM (Read Only Memory) 3, RA
An M (Random Access Memory) 4, a scale detection device 5, a keyboard 6, a display 7, a printer 8, a tone generation circuit 9, an audio system 10, a speaker 11, and the like are provided. .

The ROM 3 stores a program or the like as a tone generator using the musical scale detecting device of each invention of the present invention, and timbre data as shown in FIG. 15, and stores the musical scale detecting device as necessary. Data necessary for operating as the used tone generator is stored.

The CPU 2 controls each part of the musical tone generating device 1 according to a program in the ROM 3 and performs processing as a musical tone generating device using the musical scale detecting device of each invention of the present application.
As shown in FIG. 15, the CPU 2 has an FAS (arithmetic circuit) 21, a tone buffer 22, a polypitch extraction data buffer 23, a maximum level buffer 24, a specific tone range buffer 25, and the like. , And to the DSP 44 via the bus 12 in FIG.

The arithmetic circuit 21 performs various arithmetic processes as the CPU 2, and executes R and R in accordance with a program in the ROM 3.
Using the AM4 as the work memory, the data in the RAM4 and the R
Using the data in the OM3, a process as a tone generator is performed, and a chromatic tone detected by each invention of the present application is subjected to a tone generation process with a predetermined timbre based on its range and level. The timbre buffer 22 stores timbre data specified by a keyboard or the like from timbre data (timbre waveform data) in the ROM 3. The timbre data stored in the timbre buffer 22 includes a tone generation circuit, which will be described later, together with a chromatic tone to be generated. 9 is output.

In the polypitch extraction data buffer 23, D
The data of the scale tones detected in SP44, specifically, the scale number and its level, are stored. The maximum level buffer 24 stores the maximum level of the scale pitch and its level in the polypitch extraction data buffer 23 as described later. Arithmetic circuit
Extracted at 21 and stored.

The specific pitch range buffer 25 stores a lower pitch scale number and an upper pitch scale number of a predetermined pitch in order to extract a pitch pitch within a predetermined pitch range from the pitch pitch stored in the polypitch extraction data buffer 23. The upper limit and lower limit scale numbers set in the range buffer 25 can be appropriately set according to the range to be selected from the scale sounds stored in the polypitch extraction data buffer 23.

Therefore, the arithmetic circuit 21, the polypitch extraction data buffer 23 and the specific range buffer 25 are provided with a range determining means for determining whether or not the scale tone detected as a whole is within a predetermined reference range. The arithmetic circuit 21, the polypitch extraction data buffer 23, and the maximum level buffer 24 constitute level detection means for comparing each scale tone of each range determined by the range determination means as a whole with a predetermined reference level. doing. Further, the CPU 2 functions as control means for giving predetermined timbre data and outputting it to the musical tone generating means (musical tone generating circuit 6) depending on which scale of the musical scale sound is the detected musical scale sound.

The RAM 4 stores data for operating a scale detecting device 5 to be described later as a digital filter and an envelope extracting device, and also functions as a work memory for the CPU 2.

The scale detecting device 5 includes a microphone 41, a low-pass filter 42, an A / D converter 43, a DSP 44, a filter coefficient ROM 45, a work RAM 46, and the like, and a line input LINE IN as an input terminal for an acoustic signal. ing.

The scale detecting device 5 includes a microphone 41
Alternatively, after appropriately filtering the acoustic signal input from the line input LINE IN (this may be a musical instrument sound, a human voice sound, or a reproduced sound from a tape recorder, a radio, a television, a CD player, or the like) by the low-pass filter 42 as appropriate. , at a suitable sampling frequency f _s, converted from the a / D converter 43 into a digital signal X (n), and inputs to the DSP 44.

The filter coefficient ROM 45 stores various coefficients necessary for causing the DSP 44 to function as digital filtering, and is read and output to the DSP 44 as needed.

The work RAM 46 is a work memory when the DSP 44 operates as a digital filter. The work RAM 46 is used for data for filtering operation, and for operation by the digital input signal X (n) input from the A / D converter 43 and the DSP 44. The processed waveform signal and the like are stored.

As will be described later, the DSP 44 performs arithmetic processing using the coefficients stored in the filter coefficient ROM 45 and the work RAM 46, executes digital filtering processing, and executes envelope extraction processing.

The processing result of the DSP 44 is sent to the CPU 2, and the CPU 2 executes the processing of the scale detecting device 5 based on the detection result of the scale detecting device 5 and the storage state of various modules built in the musical tone generating circuit 9 described later. The state of the detected scale and the state of the musical tone generated by the musical sound generating device 9 is determined, and the processing of assigning or deleting the musical scale to the generating module of the musical sound generating circuit 9 is performed.

The keyboard 6 is provided with a function switch, a keyboard, and the like. When an operation of a switch, a keyboard, or the like is performed on the keyboard 6, the CPU 2 detects the operation and generates a sound module of the tone generation circuit 9. To the generated musical tone.

The display 7 and the printer 8 have a CP
It operates under the control of U2 and detects 1
Or displaying a plurality of musical scales and printing on paper. For example, the CPU may display the scale included in the sound being input in real time on the display 7, or may display the musical scale on the display 7 in a non-real time manner after editing work or the like, Or print it.

The scale detecting device 5 performs digital filtering processing of different characteristics sequentially on a digital waveform signal representing an acoustic signal in a time-division manner, thereby obtaining a level of a frequency spectrum related to a frequency corresponding to each scale. Digital signal processing means for detecting
And functions as a scale detecting means for detecting one or a plurality of scale sounds contained in the sound signal based on the processing result of the digital filtering by the digital signal processing means.

As the tone generator 9, various types of tone generators can be applied.
A sound source generating circuit of the M type, the iPD type, the sine wave synthesis type, or the like is applied. The tone generating device 9 has a plurality of tone generating channels, for example, four channels, and drives the audio system 10 to transmit a scale tone of a scale number assigned to the sound generation module of the CPU 2 to the speaker 11. The sound is output via the.

As the audio system 10, a normal audio system is used. In addition to the signal from the tone generation circuit 9, the audio system 10 is supplied with a microphone 41 and a line input LINE IN signal.
Output as sound output as required. Further, the tone generation circuit 9 can generate a tone signal of a tone according to the tone color designation of the keyboard 6, and in this case also, the CPU 2 assigns a scale tone to be output to a sound generation module to perform a tone generation operation. Further, the CPU 2 sequentially stores the change of the scale sound detected by the scale detection device 5 as sequencer information in the RAM 4, sequentially reads out the sequencer information in response to a play start instruction of the keyboard 6, and reads out the sequencer information from the musical tone generation circuit 9. It is also possible to generate a corresponding tone signal. Also in this case, chattering prevention processing and the like described later can be performed.

<Configuration of DSP> FIG. 16 shows a DSP functioning as a digital filter and an envelope extraction circuit.
(Digital Signal Processor: Digital Signal Pro
FIG. 4 is a circuit configuration diagram of the processor 44. The DSP 44 includes an interface 441, an operation ROM 442, an address counter 443, a decoder 444, a multiplier 445, and an adder / subtractor 446.
, A register group 447, a flag register 448, and the like.

The interface 441 is connected via a bus.
14 is connected to the CPU 2 and the A / D converter 43 shown in FIG.
Sound input signal or CPU2 through interface 441
, And a scale signal as a processing result is output.

The operation ROM 442 stores a program as a digital filter and an envelope extraction circuit used for a tone generator using the scale detection device of the present invention. The program memory 2 stores the address of the address counter 443. , The contents of the program are sequentially output to the decoder 444 and output to each unit.

The decoder 444 has an operation ROM 44
2 and decodes the contents of the program read out from 2 and outputs it to each part of the DSP 44 as a control signal.

The scale detecting device 5
The filter coefficient ROM 45 and the work RAM 46 are connected, and coefficient data and waveform signals are supplied to the DSP 44 as appropriate according to the program in the operation ROM 442.
The waveform signal calculated by the DSP 44 is stored in the work RAM 46.
Is output and written.

The multiplier 445 multiplies the input data and outputs the result of the multiplication to the adder / subtractor 446, the register group 447 and the like. The adder / subtractor 446 performs an addition process or a subtraction process on the input data, outputs the operation result to the multiplier 445, the work RAM 46, or the like via the register group 447, and outputs the sign data of the operation result to the flag register 448.

The flag data of the flag register 448 is output to the address counter 443, and the address counter 443
The contents of the program output from the operation ROM 442 are determined by the flag data of the flag register 448. That is, judgment processing is performed by the flag data of the flag register 448.

Next, the operation will be described. The processes of the inventions of the present application are mainly classified into a scale detection process of detecting a scale tone from an input acoustic signal, and a sound generation process of generating the detected scale tone in a predetermined tone or the like according to its range and level. Can be. Hereinafter, the scale detection processing and the sound generation processing will be described.

<Scale detection processing> First, the scale detection processing in the scale detection device 5 will be described. The scale detection process uses CP
This is performed under the control of U2, and the scale detection processing is performed by the digital filter processing described in the improved principle. CP
U2, as shown in FIG. 17, first performs an initial process at the start of the scale sound detection process (step S1).
This initial processing is mainly processing for clearing the work RAM 46.

When the initial processing is completed, it is checked whether the digital conversion of the audio signal into the digital signal X (n) by the A / D converter 43 is completed (step S).
2) When the digital conversion is completed by the A / D converter 43,
The digital signals X (n) input from the A / D converter 43 are sequentially address-set and stored in the work RAM 46 (step S3). In this case, by using a specific area of the work RAM 46 as a ring buffer (a buffer formed by virtually connecting the end and the start), an unlimited input signal (digital signal X (n)) can be obtained. Can respond.

When the digital signal X (n) is stored in the work RAM 46, the CPU 2 operates the DSP 44 as an FIR high-pass filter H ₁ (z) (step S4).
In the operation processing as the FIR high-pass filter H ₁ (z), the address setting of the program in the operation ROM 442 of the DSP 44 is performed to the address counter 443, and the coefficient setting of the filter coefficient ROM 45 is performed for the high-pass filter H ₁ (z). This is done by setting.

The calculation as the high-pass filter H ₁ (z) is based on the above equation (1). In addition to the input digital signal X (n) of this time, the input digital signal input X (n -1), X (n-2) and read DS
The processing is performed using the multiplier 445 and the adder / subtractor 446 in P44.

When the operation as the high-pass filter H ₁ (z) is completed, the set value t for performing the filter process for each scale is set to the initial set value t = 1 (step S5), and the low-pass filter H _2t ( The filtering operation as z) is performed (step S6). The calculation as the low-pass filter H _2t (z) is based on the above equation (2), and the coefficients CY, 2r cos θ, and r ² are calculated as filter coefficients R
While reading from the OM45, the multiplier 445 in the DSP44,
This is performed using the adder / subtractor 446. This calculation result W _t
(n) also stores sequentially using another specific area of the work RAM 46 as a ring buffer. Also in this case, by using the work RAM 46 as a ring buffer, the result of the previous and second previous calculations W _t (n−
1), W _t (n−2) can be read out one after another and used for calculation.

When the arithmetic processing as the high-pass filter H ₁ (z) and the low-pass filter H _2t (z) is completed, the envelope extraction processing for each scale is performed next. In this envelope extraction processing, DSP44 is set to IIR for each scale.
Run by the arithmetic processing as a low-pass filter H _E (z) (step S7).

[0088] The operation of the low-pass filter H _E (z), due to the above formula (3), each coefficient CE, 1.8, -
While reading 0.81 from the filter coefficient ROM 45, DS
This is performed using a multiplier 445 and an adder / subtractor 446 in P44. Of these operations, the absolute value calculation | W _t (n) | is also performed using the adder / subtractor 446.

The operation result E _t (n) is also stored sequentially by using another specific area 46 of the work RAM 46 as a ring buffer, so that the previous and last operation results E _t (n− 1), E _t (n−2) can be read out one after another and used for calculation.

When the filtering process and the envelope extracting process are completed, it is checked whether or not these processes have been performed (t = N) for all scales (step S).
8) If the processing has not been completed for all the scales, the set value t is incremented (step S).
9) Go to step S6. When the process proceeds to step S6, the filtering process of steps S6 and S7 is executed again.

In step S8, if the filter processing or the like has been completed for all the scales, the envelope E _t (n) (t = 1 to N) for each scale is notified to the CPU 2 (step S10). It is checked whether or not the scale detection processing mode is to be ended (step S11). When the scale detection processing mode is not ended, the process proceeds to step S2, and the same processing is performed after waiting for A / D conversion of the next acoustic signal.
That is, the DSP 44 performs the digital filtering of the three systems in a time-division manner in a time-division manner and repeatedly for each scale, thereby real-time, in accordance with the envelope of each scale, the frequency related to the frequency corresponding to each scale. The level of the spectrum can be detected.

In step S11, when the CPU 2 notifies the DSP 44 of the end of the scale detection processing mode by operating the keyboard 5 or the like, a series of processing operations is ended.

<Detection Sound Generation Processing of CPU2> CPU2
Is, as described above, the envelope signal E _t (n) (t = 1 to
N), that is, since the level of the frequency spectrum related to the frequency corresponding to each scale is given, it can be used for various purposes. However, if each given scale is output as a musical tone as is, Since the sounds are also pronounced in exactly the same tone, they lack musicality or sound.

Therefore, in each invention of the present application, a musical tone rich in musicality is generated by generating or not generating a tone based on the detected tone range or level of the scale tone, or by generating a tone by changing the timbre. I can do it.

In the following, a description will be given of a process of selecting a range and a level state of a scale tone and a process of generating a sound in the case of the present embodiment. C
As shown in FIG. 18, the PU 2 first performs an initialization process (initial process) in order to perform a scale sound generation process (step P1). By this initial setting process, the timers and flags described later and the work RAM 46 are cleared.

When the initial setting process is completed, it is checked whether or not a scale sound detection end signal indicating that the scale sound detection process in the scale detecting device 5 has been completed is input from the scale detecting device 5 (step P2). when chromatic notes detection end signal is input, and writes the envelope value of each chromatic note is scale detection device 5 detects E _t (n) to RAM 4 (step P2). When the writing of the detected envelope values E _t (n) of the respective scale sounds to the RAM 4 is completed, up to four of the envelope values E _t (n) of the respective scale sounds are taken out in descending order, and MAXENV0, 1,. 2, 3 (step P3), and the largest M among MAXENV0, 1, 2, 3
Judge whether AXENV0 exceeds a predetermined threshold value.

The setting of the threshold value is performed, for example, as follows. Now, the input signal X (n) from the A / D converter 43 to the DSP 44 is set to, for example, a maximum of ± 100. If the value of the envelope value _Et (n) output from the CPU to the CPU 2 is, for example, 1000, 2
In the input of scale notes, the input of each scale note is ± 50,
The envelope value is 500 for each scale, and similarly 250 for a 4-scale input. Here, if this threshold value is set to be large, there is a possibility that a result may occur in which no chromatic note can be detected for a multiple tone input. Therefore, for example, the number of scale to be extracted is set to N (=
50), the envelope maximum value (= 1000) ÷ N
(= 50) = 20 is set as the threshold value.

In step P4, if MAXENV0 does not exceed this threshold value, it is checked whether there is a tone being generated, that is, whether there is a tone signal being generated by the tone generation circuit 9 (step P5). If there is no middle tone, the process returns to step P1 and the DSP
In preparation for inputting the envelope value E _t (n) of the next scale note from 44.

In step P5, if there is a tone being generated, the microphone 41, the line input LINE IN, etc.
The CPU 2 determines that the sound input of the scale sounds adopted as XENV0, 1, 2, and 3 has stopped, and the CPU 2
Is instructed to start mute (step P6), and step P1
To prepare for the input from the next DSP 44.

If the value of MAXENV0 exceeds the predetermined threshold value in step P4, a counter i for setting the number of musical tones to be generated is set to 1 (step P4).
7) It is checked whether MAXENVi is larger than a predetermined threshold (Step P8). When MAXENVi is larger than a predetermined threshold, MAXENVi
It is checked whether or not it is larger than 1 / m of XENV0 (step P9). If MAXENVi is larger than 1 / m of MAXENV0, the counter i is incremented by 1 and i is 3 which is the number of musical tones to be generated. Check whether the value is exceeded (step P
11).

This m is a factor that determines to what extent the level of the next scale tone is cut from the input scale tone. According to the principle of each invention of the present application, when one scale tone is input, Since the envelope value of the next scale tone also slightly increases (because the leakage of the next scale tone affects), the value of m used in designing the low-pass filter H _2t (z) is To determine if the scale is really input.

It is to be noted that the value of m can be used by obtaining a condition that does not cause an erroneous input in an experiment or the like. Further, if the scale can be correctly determined, the contents of the determination processing in Steps P8 and P9 can also be determined. Various changes can be made.

When the counter i has not reached 3,
Returning to Step P8, similarly, it is checked whether MAXENVi exceeds a predetermined threshold value and whether MAXENVi is larger than 1 / m (Step P8 to Step P11).

If MAXENVi does not exceed the threshold value in step P8, if MAXENVi does not exceed 1 / m of MAXENV0 in step P9, or if counter i exceeds 3 in step P11,
A polypitch extracted data buffer for the scale sounds of these MAXENV0 to MAXENV _i-1
23, and compares it with the extracted tones that are the basis of the tone signal currently being generated by the tone generation circuit 9, and enters a process for changing the channel assignment state as necessary (step P12). ).

That is, first, a counter j for designating each tone generating channel is reset to 0 (step P13).
Whether or not the j-th scale currently being pronounced is included in the to-be-produced target, that is, the scale tones that are the basis of the generated tones in the j-th musical tone generation channel is a maximum of four to-be-produced scales extracted this time. It is checked whether it is included in the sound (step P14). When the j-th scale currently being pronounced is included in the subject to be pronounced, the j-th scale tone is excluded from the subject for starting the pronunciation (step P15), and the tone currently being generated continues to be produced. When the j-th scale currently being pronounced is not included in the sound target, the scale sound that has been the source of the tone generated in the j-th tone generation channel so far is included in the input audio signal. It is determined that the sound has not been played, and a sound-extinguishing instruction for the scale tone of the j-th musical tone generating channel is issued (step P16). Step P15 and Step P
When the process of step 16 is completed, the counter j is incremented by one, and it is checked whether the value of the counter j has exceeded 3, that is, whether or not the tone has been assigned by the number of tone generating channels (step P18). If j does not exceed 3, the process returns to step P14, and the same processing is repeated until the assignment of musical tones is completed by the number of musical tone generating channels.

When the assignment of the musical tones is completed by the number of the musical tone generating channels, the tone generation based on the tone range shown in FIG. 19 or FIG. 20 is performed, and then the tone generating process is performed (step P19). . Upon completion of the musical tone generation processing, the process returns to step P1, and the same processing is performed on the next detected scale note to be input.

Next, a description will be given of a selection process based on a range and a level of an extracted sound and a tone generation process. First, a process for stopping the generation of a musical tone based on the range and the level of the extracted sound will be described.

In FIG. 19, as described above, the CPU 2 performs processing for determining whether the scale and level of the polypitch extracted data given by the KI from the DSP 44 are to be subjected to sound generation based on the envelope value. First, the maximum level buffer 24 shown in FIG. 15 is cleared (step T1). Based on the scale data in the first buffer of the polypitch extraction data buffer 23, the scale data is determined to be within a specific range. It is checked whether the data is data (step T2). Checking whether or not the data is in the specific range is performed by comparing the scale data in the first buffer of the polypitch extraction data buffer 23 with the specific range buffer 25.
The lower limit scale data and the upper limit scale data are compared by the arithmetic circuit 21.
This is performed by designating a specific range to be set and writing the range data to the specific range buffer 25.

When the extracted scale data is data within a specific range, the extracted scale data is stored in the maximum level buffer 24.
It is checked whether the extracted scale data is higher than the level of the maximum level buffer 24 by comparing the extracted scale level with the arithmetic circuit 21 (step T3), and the extracted scale data is higher than the level of the scale data of the maximum level buffer 24. Sometimes, the contents of the extracted scale data (scale number (TONE N
o.)) and its level are written in the maximum level buffer 24 (step T4). That is, the contents of the maximum level buffer 24 are replaced with the extracted scale data currently being determined.

Next, it is checked whether the judgment of all the data fetched into the polypitch extraction data buffer 23 has been completed (step T5). If not, the process returns to step T2 and the next step of the polypitch extraction data buffer 23 is performed. The selection process based on the scale is similarly performed on the extracted scale data of the buffer of No.

If it is determined in step T2 that the extracted scale data is not the scale data within the specific range, the process proceeds to step T5, where it is checked whether or not the next extracted scale data is to be selected. If the level is not higher than the level in the maximum level buffer 24, the process shifts to step T5 without replacing the data in the maximum level buffer 24, and checks whether or not to perform a process of selecting the next extracted scale data. By the above-described steps T2 to T5, it is possible to select the chromatic note of the maximum level within the specific range from the extracted data.

When the extraction of the maximum scale tone within the predetermined range from the extracted scale tones is completed, the arithmetic circuit 21 again sequentially starts from the data of the first buffer of the polypitch extraction data buffer 23 by the arithmetic circuit 21 again. It is checked whether the extracted scale tone (data in the polypitch extraction data buffer 23) is data of the maximum level buffer 24 (step T6), and the scale pitch of the polypitch extraction data buffer 23 is set to the maximum level. Buffer 24
If not, the tone number (TONE No.) of the extracted data and the other tone color data in the tone color buffer 22 are output to the tone generating circuit 9 (step T7). In the timbre buffer 22, waveform data of a timbre to be sounded is read from a timbre buffer in the ROM 3 and stored in advance, and is stored in another timbre buffer in the timbre buffer 22 in the processing in FIG.

Next, it is checked whether or not the sound generation processing of the scale sounds in all the polypitch extraction data buffers 23 has been completed (step T8). Returning to step T6, it is checked whether or not the scale note in the next polypitch extraction data buffer 23 is the scale data in the maximum level buffer 25. If the extracted scale data is the scale data of the maximum level buffer 24, the extracted scale data is not output to the tone generation circuit 9 and the process proceeds to step T.
Then, the process goes to step 8 to check whether or not the tone generation processing of all data has been completed.

When the above processing is completed for all scale data taken into the polypitch extraction data buffer 23,
Assuming that all sound generation processes have been completed, step P1 in FIG.
Return to Note that the musical tone generation circuit 9 generates the input scale data in accordance with the input timbre data together with the scale data.

As described above, in the tone selection process based on the tone range and the level shown in FIG. 19, it is possible to stop the output to the tone generating circuit 9 of the tone level of the maximum level among the preset tone sounds of the specific tone range set in advance. In addition, it is possible to prevent generation of an arbitrary scale sound among the extracted scale sounds. Therefore, it is possible to prevent, for example, a chromatic note corresponding to the main melody from being produced in the input acoustic signal. That is,
The extracted data covers the entire range from low frequencies to high frequencies, but the extracted data that corresponds to the main melody is considered to exist in a specific range of the entire range, and the level of the data in the specific range The largest one can be considered the main melody. Therefore, the so-called minus one effect can be exhibited by setting the specific range, selecting the extracted scale data of the maximum level among them, and stopping the generation of the extracted scale note of the maximum level.

Next, a description will be given of a process for changing a timbre for generating a musical tone based on a tone range and a level. In this process, the same selection process based on the sound range and the level as the process shown in FIG. 19 is performed, and the same process numbers as those in FIG. 19 are denoted by the same step numbers as those in FIG. 19, and description thereof is omitted. I do.

In FIG. 20, steps T1 to T
By performing the processing of step 5, extraction of the maximum scale musical note within the predetermined range from the extracted musical scale notes is performed. Next, in step T6, the extracted data of the polypitch extracted data buffer 23 is replaced with the data of the maximum level buffer 24. Check if it is. In step T6, the polypitch extraction data buffer 23
Is determined not to be the data of the maximum level buffer 24, the scale number (TONE N
o.) and the timbre data of timbre 2 stored in the other timbre buffers of the timbre buffer 22 to the tone generator 9 (step U1). It is checked whether the sound generation process has been completed (step T8). If the tone generation processing for all the data fetched into the polypitch extraction data buffer 23 has not been completed, the process returns to step T6 to check whether the next extraction data of the polypitch extraction data buffer 23 is the data of the maximum level buffer 24. When it is determined that the extracted data of the polypitch extracted data buffer 23 is the data of the maximum level buffer 24, the scale number (TONE No.) of the data and the timbre 1 stored in the maximum level buffer of the timbre buffer 22. Is output to the tone generation circuit 9 (step U2), and it is checked whether or not the tone generation processing of all the data taken into the polypitch extraction data buffer 23 has been completed (step T8).

When the above processing is completed for all scale data taken into the polypitch extraction data buffer 23,
Assuming that all sound generation processes have been completed, step P1 in FIG.
Return to In the maximum level buffer and the other timbre buffers of the timbre buffer 22, data of a timbre to be generated in advance for a chromatic tone of the maximum level in a specific gamut is stored in advance.
In the other timbre buffers of the timbre buffer 22, timbre data to be generated for chromatic tones other than the chromatic tones of the maximum level in the specific timbre are designated and stored. The storage of the timbre data in the timbre buffer 22 is performed, for example, by designating it with the keyboard 6 or the like.
3 by writing the timbre waveform data in the timbre data buffer 22.

As described above, in the tone selection process based on the tone range and the level shown in FIG. 20, among the extracted tone sounds of the specific tone range set in advance, different tone colors are used for the tone of the maximum level and the tone other than the maximum level. Can be pronounced. Therefore, by storing the timbre data desired to be emitted as the main melody in the timbre buffer at the maximum level of the timbre buffer 22, and storing the timbre data desired to be emitted for other than the main melody in the other timbre buffers of the timbre buffer 22. It is possible to produce different timbres depending on the chromatic note corresponding to the main melody and the chromatic note which is not the main melody. As a result, a more musical performance can be performed as compared with the conventional case where all scale data are generated in the same tone.

In the above-described embodiment, the maximum level is detected only for the chromatic tones within the specific range, and the generation of the sounds is stopped or the timbre is changed so that the sounds are generated. Instead, a plurality of reference tone ranges and a plurality of reference levels can be set, and the tone color generated can be made different depending on each tone range and level. For example, a specific range is set in the middle range, a tone appropriate for the main melody is assigned to the highest level in the range, a specific range is set in the low range, and a bass tone is assigned to the highest level in the range. A timbre suitable for a decorative sound may be set in the remaining data. In this case, a more musical performance can be performed.

In the above embodiment, the case where the number of channels of the tone generating circuit 9 is four has been described. However, the present invention is not limited to this and can be set arbitrarily.

[0122]

According to the first aspect of the present invention, a scale tone detected by performing a digital filtering process on an acoustic signal generated from a musical instrument such as a piano, an electronic musical instrument, or the like is used as a musical note whose musical scale is set in advance. It can be produced with different timbres depending on the level of the scale sound that is within the reference range. Therefore, it is possible to perform a musically rich performance as compared with the related art in which all the detected scale sounds are produced in the same timbre.

According to the second aspect of the present invention, of the detected scale notes, only the scale notes other than the scale note having the predetermined reference level or higher within the predetermined reference range are generated with the predetermined tone color, and the predetermined scale range within the predetermined reference range is generated. It is possible to prevent the generation of a chromatic sound higher than the reference level. Therefore, a so-called minus one effect can be exhibited.

According to the third aspect of the present invention, the input acoustic signal is subjected to digital filtering processing, and the scales detected by the scale are converted into a scale sound exceeding a predetermined reference level within a predetermined reference range and other scale sounds. Can be produced with different timbres. Therefore, it is possible to generate a sound with two kinds of timbres, and it is possible to perform a musical performance.

According to the fourth aspect of the present invention, the input acoustic signal is subjected to digital filtering processing, and the scale sounds detected by the scale are classified based on a plurality of ranges, and are classified based on a plurality of levels. , Different tones can be given, and sounds of different tones can be produced according to the range and level. As a result, sounds of different parts can be pronounced as sounds of different timbres, and a more musical performance can be performed.

According to the fifth to eighth aspects of the present invention, all signal processing can be performed in the digital domain, and high-speed and efficient scale extraction processing can be performed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram showing a basic principle of an embodiment of a musical sound detecting device and a musical sound generating device using the same according to the present invention.

FIG. 2 is a frequency characteristic diagram of the band-pass filter H _t (z) of FIG. 1;

FIG. 3 is a configuration diagram based on a principle obtained by improving FIG. 1;

FIG. 4 is a frequency characteristic diagram when the high-pass filter H ₁ (z) and the low-pass filter H _2t (z) of FIG. 3 are connected in cascade.

FIG. 5 is a configuration diagram of a high-pass filter H ₁ (z) of FIG. 3;

FIG. 6 is a frequency characteristic diagram of the high-pass filter H ₁ (z) of FIG. 5;

FIG. 7 is a configuration diagram of a low-pass filter H _2t (z) of FIG. 3;

FIG. 8 is a diagram showing poles and zeros and pole vectors and zero vectors of the digital filter of FIG. 7;

9 is a diagram illustrating frequency characteristics corresponding to FIG.

FIG. 10 is a frequency characteristic diagram of the low-pass filter H _2t (z) of FIG. 7;

Figure 11 is a configuration diagram of a low pass filter H _E (z) in FIG.

[12] frequency characteristic diagram of the low-pass filter H _E (z) in FIG. 11.

FIG. 13 is an explanatory diagram for explaining that envelope extraction is performed by the configuration of FIG. 11;

FIG. 14 is an overall circuit configuration diagram of an embodiment of a musical sound detection device and a musical sound generation device using the same according to the present invention.

FIG. 15 is a diagram illustrating a configuration diagram and an arithmetic circuit of each buffer formed in the CPU 2 of FIG. 14;

16 is an internal circuit configuration diagram of the DSP 44 in FIG. 14;

FIG. 17 is a flowchart of digital filter processing and envelope extraction processing by the DSP 44 of FIG. 16;

FIG. 18 is a flowchart showing a detected scale sound generation process by the CPU 2 until the musical tone generation device 9 generates and stops the scale detected by the scale detection device 5.

FIG. 19 is a flowchart showing a process for stopping the generation of a chromatic note having a maximum level in a predetermined musical range and generating another chromatic note in a predetermined timbre.

FIG. 20 is a flowchart showing a process for generating a chromatic note having a maximum level in a predetermined range and generating another chromatic note in different timbres.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Music tone generator 2 CPU 3 ROM 4 RAM 5 Scale detection device 6 Keyboard 7 Display 8 Printer 9 Music tone generator 10 Audio system 11 Speaker 12 Bus 22 Tone buffer 23 Polypitch extraction data buffer 24 Maximum level buffer 25 Specific tone range buffer 44 DSP 45 Filter coefficient ROM 46 Work RAM

Claims (8)

(57) [Claims] An acoustic signal is analyzed by a scale detecting device,
A musical tone generating device that detects a chromatic tone included in the acoustic signal and generates the detected chromatic tone with a predetermined tone, and performs digital filtering processing of different characteristics on a digital waveform signal as an acoustic signal in a time-division manner. Digital signal processing means for detecting a level of a frequency spectrum related to a frequency corresponding to each scale by sequentially performing the processing, and one or more scales included in the acoustic signal based on a result of digital filtering performed by the digital signal processing means. Scale detecting means for detecting a sound, range determining means for determining whether or not the scale sound detected by the scale detecting means is within a predetermined reference range, and each range determined by the range determining means Level detecting means for comparing each chromatic note with a predetermined reference level; And Could tone generation means by,
On the basis of the sound range judgment result of the sound range judgment means and the level detection result of the level detection means, predetermined tone color data is given to the tone generation means by adding predetermined tone color data in accordance with which scale sound level of the detected scale sound is. Control means for outputting to
A tone generator using a scale detection device, comprising: 2. The musical tone generating means according to claim 2, wherein said control means outputs only musical scale sounds other than musical scale sounds having the predetermined reference level or higher in said predetermined standard range to said musical tone generating means, among the musical scale sounds detected by said musical scale detecting means. The musical tone generator using the musical scale detecting device according to claim 1, wherein the musical tone is output as a musical scale tone. 3. The musical tone generating device according to claim 1, wherein said control means is adapted to generate, with respect to a chromatic tone higher than said predetermined reference level within said predetermined reference gamut, among said chromatic sounds detected by said scale detecting means, together with said timbre data, said musical tone generation. And outputting to the musical tone generating means together with timbre data other than timbre data assigned to the chromatic tone, for chromatic tones other than chromatic tones of a predetermined reference level or higher within the predetermined reference gamut. A musical tone generating device using the musical scale detecting device according to claim 1. 4. The sound range discriminating means judges whether or not the scale sound detected by the scale detecting means is within a plurality of preset reference sound range ranges. Each of the determined scale tones is compared with a plurality of reference levels, and a comparison result for each of the reference levels is output to the control unit. On the basis of a level detection result, each scale sound detected by the scale detection means is assigned to a predetermined tone color data for each of the plurality of reference ranges and the plurality of reference levels, and is output to the musical tone generation means. A musical sound generating device using the musical scale sound detecting device according to claim 1. 5. The digital signal processing means according to claim 1, wherein said digital signal processing means sequentially executes band-pass filtering processing using a frequency corresponding to each of said scales as a center frequency in a time division manner. A musical sound generator using the musical scale sound detecting device according to claim 3 or 4. 6. The digital signal processing means sequentially executes band-pass filtering processing using a frequency corresponding to each of the scales as a center frequency in a time-division manner, and performs envelope processing on a waveform signal obtained as a result of the band-pass filtering processing. 5. The scale according to claim 1, wherein a level of a frequency spectrum related to a frequency corresponding to each scale is detected by sequentially performing a signal processing operation for extracting the scale. A tone generator using a sound detector. 7. The digital signal processing means performs a high-pass filtering process of a predetermined characteristic and sequentially executes a low-pass filtering process to which a resonance having a peak at a frequency corresponding to each scale is added in a time-division manner. Claim 1, Claim 2, Claim 3
A tone generator using the scale note detector according to claim 4. 8. The digital signal processing means performs a high-pass filtering process having a predetermined characteristic, and sequentially executes a low-pass filtering process in which resonance having a peak is added at a frequency corresponding to each scale by time division. The level of a frequency spectrum related to a frequency corresponding to each scale is detected by sequentially performing signal processing operations for extracting an envelope from a waveform signal obtained as a result of these digital filtering processes. A musical sound generator using the musical scale sound detecting device according to claim 2, 3 or 4.