JPH0734154B2 - Electronic musical instrument - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Field of Industrial Application> The present invention relates to an electronic musical instrument.

<Prior Art> Conventionally, in a string instrument or a wind instrument, a tube vibration is converted into an electric signal, a frequency or a period (pitch information) corresponding to a fundamental frequency (pitch) of the vibration is detected, and the detected vibration is detected. Some sound sources are produced according to the number or cycle.

<Problems to be Solved by the Invention> In the following, taking a guitar synthesizer as an example, in the guitar synthesizer, it is necessary to detect the accurate frequency of the string, and therefore, the vibration cycle of the string is detected over several cycles. , It took time to determine the frequency at lower frequencies. For example, if the frequency of the string is 50 Hz, one cycle is 20 msec, and if you try to detect the frequency from the waveform of several cycles, it takes at least 100 msec and the string actually starts vibrating. There was a problem in that there was a time delay between the time the sound was played and the time the sound was pronounced. There is also a problem in that each string cannot be sounded at an accurate pitch unless it is tuned accurately. Some guitars with frets, such as guitars, detect which fret position is being pressed by the player and determine the frequency of the string by this (JP-A-59-176783). Although the above problem does not occur, there is a problem that the mechanism becomes complicated.

It is an object of the present invention to provide an electronic musical instrument that solves the above problems.

<Means for Solving the Problems> In order to achieve the above object, the first invention is a means for detecting pitch information corresponding to a fundamental frequency of a tone signal, a means for switching between a storage mode and a performance mode, First storage means for storing reference pitch information corresponding to the reference frequency, second storage means for storing pitch information detected by the detection means in the storage mode, and detection by the detection means in the performance mode. It is provided with means for changing the pitch information based on the pitch information stored in the first storage means and the pitch information stored in the second storage means.

According to a second aspect of the invention, the second storage means stores the pitch information detected by the detection means in the storage mode by changing it based on the reference pitch information stored in the first storage means. The changing means changes the pitch information detected by the detecting means in the playing mode based on the numerical value stored in the second storage means.

As the pitch information, it is desirable to use a numerical value corresponding to the period or frequency of the fundamental frequency of the musical tone signal, or a numerical value obtained by logarithmizing the fundamental frequency.

<Operation> In the first aspect of the invention, in the state in which the storage mode is set by the switching means, the detection means is caused to detect the pitch information to be associated with the pitch information stored in the first storage means. It is stored in the storage means. The pitch information detected by the detecting means is changed to the pitch information corresponding to the fundamental frequency of the tone signal to be generated based on the pitch information in the first and second storing means in the state where the switching means is set to the performance mode. .

In the second aspect of the invention, in the storage mode, the detection means detects the pitch information to be associated with the pitch information stored in the first storage means, and changes the pitch information based on the pitch information in the first storage means. , In the second storage means. Further, in the performance mode, the pitch information detected by the detecting means is changed to pitch information corresponding to the fundamental frequency of the tone signal to be generated based on the stored value of the second storing means.

<Example> Hereinafter, the present invention will be described in detail based on two examples in which the present invention is applied to a guitar synthesizer. First Example First
Shown in the figure. In the figure, reference numeral 2 denotes a pickup, which is arranged on the guitar so as to detect the vibration of one of a plurality of strings provided on the guitar (not shown).

The vibration of the string detected by the pickup 2 is supplied to the pitch detection unit 4, where the fundamental frequency (pitch) of the string is detected. The detected frequency is selectively supplied to the memory 8 and the calculating means 10 via the changeover switch 6. The configurations of the pickup 2 and the pitch detector 4 are publicly known, and detailed description thereof will be omitted.

The changeover switch 6 switches between the storage mode and the performance mode. In the storage mode (at this time, the string serves as a reference, for example, the open state in which neither of the frets is pressed). The pitch A in the reference state of the strings detected by the detection unit 4 is stored in the memory 8.
When the changeover switch 6 is in the play mode, the string pitch p detected by the pitch detector 4 is supplied to the arithmetic means 10.

The string A stored in the memory 8 in the storage mode is supplied to the arithmetic means 10, and the pitch B (reference pitch) of the tone to be generated corresponding to the string pitch A in the memory 8 is supplied. Is supplied from the reference pitch memory 12. The reference pitch B may be set in advance or may be freely set by the player using the setting unit 13 as shown by the dotted line in FIG. Computing means 10
In the performance mode, it tries to generate sound based on the string pitch p supplied from the pitch detector 4, the string pitch A stored in the memory 8 and the reference pitch B of the reference pitch memory 12. The pitch p'of the musical tone is calculated and supplied to the sound source 14. The pitch p ′ is calculated by the pitch p of the string detected in the performance mode with respect to the pitch A of the reference string.
Is calculated and the reference pitch B is multiplied by this ratio.

The sound source 14 generates a tone of the supplied pitch p ', and various kinds of generation methods can be used, for example, a waveform reading method, an FM synthesizing method, a harmonic synthesizing method, or the like. A device for changing the pitch of a voice signal as described in Japanese Patent Application No. 62-6870 can be used.

In the guitar synthesizer configured as described above, first, the selector switch 6 is switched to the memory mode, and the strings are played with the frets open. The vibration of the string is detected by the pickup 2, the pitch A is detected by the pitch detection unit 4, and is stored in the memory 8 via the changeover switch 6.

When the player switches the selector switch 6 to the performance mode and plays a string while holding one of the frets, the pickup 2 detects the vibration of the string in the same manner as described above, and the pitch detector 4 detects the pitch. p is detected.
This pitch p is supplied to the calculating means 10 and the calculating means 10
Calculates the pitch p'of the musical sound to be produced based on the pitch p, the pitch A stored in the memory 8 and the pitch B of the reference pitch memory 12 as p '= p.B / A. Calculated and supplied to the sound source 14. Sound source 14
Generates a tone based on the supplied pitch p '.

A second embodiment is shown in FIGS. 2 to 4. In this embodiment, the sound source 14a shown in FIG. 2 is configured to input a MIDI signal. In MIDI standard sound source 14a,
Instead of inputting the pitch, the note number corresponding to each key of the electronic keyboard instrument is input, and the musical tone is generated at the pitch corresponding to the input note number. The note number in the MIDI standard is the number corresponding to the key on the keyboard, and the note number corresponding to the frequency between adjacent keys is not standardized, but here the frequency (fundamental frequency) is expressed in logarithm. Is called a note number. When the note number is plotted on the vertical axis and the fundamental frequency is plotted on the horizontal axis, it is expressed by a logarithmic function as shown in FIG. 3, so the note number Np ′ input to the sound source 14a is Np ′ = log p ′ = log (PB / A) = log p + log B-log A = Np + NB-NA. However, Np is the pitch p of the string detected in the play mode converted to a note number,
NA is the pitch A, which is the reference of the strings detected in the memory mode, converted into a note number, and NB is the reference pitch B converted into a note number.

Therefore, in the second embodiment, the functional relations shown in FIG. 3 are stored in the ROM 16 as a look-up table, and when the mode changeover switch 6a is changed over to the storage mode, the CPU 18 first changes to the memory shown in FIG. As shown in the pitch detector 4
Converts the pitch A detected in the table into a note number NA
(Step S2). Next, the note number NB corresponding to the preset reference pitch B is read from the RAM 20, NA is subtracted from NB, and this subtraction value (NB-Na) is stored in the RAM 20 (step S4). Note that the NB-NA may be calculated after storing the reference pitch B in the RAM 20 instead of storing the NB in advance and converting the reference pitch B into a table to obtain NB. Further, the reference pitch B or NB may be configured so that the player can arbitrarily set it.

Also, when the changeover switch 6a is switched to the play mode,
The CPU 18 converts the pitch p supplied from the pitch detection unit 4 into a table to obtain a note number Np (step S6), adds (NB-NA) read from the RAM 20 to this Np, and N
p'is calculated (step S8), and this Np 'is supplied to the sound source 14a to generate a musical tone (step S10).

In both of the above-mentioned embodiments, the case where the pickup 2 is provided only on one string of the guitar has been described for simplification of description, but the pickup is provided on all six strings of the guitar, and the first pickup is provided for each pickup. In the embodiment, the memory 8 and the reference pitch memory 12 may be provided, and the calculating means 10 may be configured to calculate the pitch for each string in a time division manner.
In the second embodiment, the reference pitch B for each string or the note number corresponding to the reference pitch B for each string is stored in advance in the RAM 20, and in the storage mode (NB-NA) for each string. May be calculated and stored in the RAM 20, and in the play mode, Np 'may be calculated for each string by time division. Further, in the case of a bass guitar, pickups may be provided on all four strings, and the configuration may be the same as that described above. Needless to say, the present invention is not limited to string instruments such as a guitar synthesizer, but can be applied to wind instruments and the like.

<Effect> As described in the section of the problem to be solved by the invention, in the conventional one, when the fundamental frequency is low, the period is long and the pitch detection becomes slow. The corresponding pitch information and the pitch information of the strings or the like to be associated with this pitch information are stored, and the pitch information of the actually played strings or the like is changed by the above-mentioned pitch information to determine the pitch of the musical sound to be produced. Therefore, if a string or the like is tuned so that the pitch becomes high and the corresponding fundamental frequency is set low, the pitch is detected quickly and the pitch information is changed to be low. Therefore, even if the fundamental frequency is low, it is possible to prevent a time delay from the time the string is played until the sound is generated. Moreover, it is possible to obtain a desired musical sound without accurately tuning the strings and the like. Also, irregular tuning can be easily performed. That is, in a state in which each fret cannot be pressed with a normal guitar, the first string is E ₄ and the second string is
B ₃ , the 3rd string is G ₃ , the 4th string is D ₃ , the 5th string is A ₂ , and the 6th string is E _2.
Tune so that the 6th string is D
₂ , I want to tune the 4th string to E ₃ . According to the present invention, such an irregular tuning can be easily performed by changing the fundamental frequency. Also, a right-handed person holds the fret with his left hand,
Play the strings with your right hand, but the left-handed person does the opposite. Therefore, the first string becomes E ₂ , the second string becomes A ₂ , ... The sixth string becomes E _4, and such a change can be easily made only by changing the fundamental frequency. Further, since the pitch detecting section, the first and second storing means, and the changing means are provided, it is more preferable to detect which one of the frets is pressed to determine the pitch of the generated musical sound. The configuration is simple.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of a first embodiment of an electronic musical instrument according to the present invention, FIG. 2 is a block diagram of the same second embodiment, and FIG. 3 is a second embodiment thereof. FIG. 4 is a diagram showing the relationship between the note number and the fundamental frequency in the MIDI standard used in FIG. 4, and FIG. 4 is a flow chart showing the operation performed by the CPU of the second embodiment. 4 ... Pitch detector, 6, 6a ... Switching means, 8, 12 ...
Storage means, 10, 18 ... Change means.

Claims (4)

[Claims] 1. A means for detecting pitch information corresponding to a fundamental frequency of a tone signal, a means for switching between a storage mode and a performance mode, and a first storage means for storing reference pitch information corresponding to a reference frequency. Second storage means for storing the pitch information detected by the detection means in the storage mode; and pitch information stored in the first storage means for the pitch information detected by the detection means in the performance mode, and the second storage means. And a means for changing the pitch information stored in the second storage means. 2. A means for detecting pitch information corresponding to a fundamental frequency of a tone signal, a means for switching between a storage mode and a performance mode, and a first storage means for storing reference pitch information corresponding to a reference frequency. Second storage means for changing and storing the pitch information detected by the detection means in the storage mode based on the reference pitch information stored in the first storage means, and detected by the detection means in the performance mode. An electronic musical instrument comprising: means for changing pitch information based on a numerical value stored in the second storage means. 3. An electronic musical instrument according to claim 1 or 2, wherein the pitch information is a numerical value corresponding to the period or frequency of the fundamental frequency of the tone signal. 4. The electronic musical instrument according to claim 1 or 2, wherein the pitch information is a logarithmic value of a fundamental frequency.