JPH0792976A - Electric string instrument and volume correction device - Google Patents

Abstract

(57) [Summary] [Purpose] Prevents crosstalk when multiple strings are played simultaneously. [Structure] Pick-up 7 to 12 on multiple strings 1 to 12
The pickups 7 to 12 also detect vibrations of strings other than the corresponding strings. The pickup 7 corresponding to a specific string is provided with an adaptive filter 20 adjusted to generate a simulated crosstalk signal simulating a crosstalk signal generated by another string 8. The output signal of the adaptive filter 20 is subtracted from the output signal of 1 by the adder 13 to remove the crosstalk.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric stringed instrument and a volume correction device.

[0002]

2. Description of the Related Art Conventionally, an electric stringed instrument is provided with a string vibration detector for detecting a string vibration in each of a plurality of strings, and a string vibration detection signal from the string vibration detector is processed and output. is there. As the above-mentioned signal processing, for example, there is one that adds effects such as distortion and overdrive.

[0003]

When the vibration of a string is detected by using the string vibration detector as described above, the vibration of a certain string is detected by the string vibration detector for another string, and the so-called so-called May cause crosstalk. In particular, when a piezoelectric type string vibration detector is used, in order to prevent crosstalk, a guitar bridge portion is provided for each string separately to prevent mutual interference. However, there was a problem that the original tone of the guitar was damaged.

Since such crosstalk occurs, when the above-mentioned effects such as distortion and overdrive are added to each string, it is necessary to distort only the signal of each string from other strings. There is a problem that the signals are mixed with each other to cause cross modulation, resulting in a muddy sound. Also,
Apart from the presence or absence of crosstalk, after adding effects such as distortion and overdrive to each string, and combining the signals with these effects added, the volume is higher than when only one string is played. There is a problem that the volume becomes high. That is, when playing with multiple notes, the amplitude is increased by the number of strings played, resulting in a large volume, and the difference from the volume when playing with a single note increases. If you add distortion or overdrive effects after mixing the signals of each string, the maximum amplitude is the same whether you play single notes or multiple notes, and there is a volume difference. However, there is another problem in that, when playing a compound note, intermodulation occurs and the sound becomes muddy.

[0005]

In order to solve the above problems, in the first aspect of the present invention, a plurality of string vibration detections are provided for each of a plurality of strings and mainly detect the vibrations of the corresponding strings. Means and a string vibration detecting means corresponding to a specific string, a simulated crosstalk signal generating means for simulating a crosstalk signal generated by another string, and an output of the string signal detecting means corresponding to the specific string. And a canceling means for canceling the simulated crosstalk signal from the signal.

Further, the second aspect of the present invention is such that a plurality of input terminals for respectively inputting a plurality of tone signals, a channel having a gain adjustment control means for each of these input terminals, and a plurality of channels for detecting the signal level in each of these channels. Signal level detection means, and a plurality of control signal generation means which are provided for each of the channels and each generate a gain control signal for the gain control means in accordance with a detection signal of each of the signal level detection signals. However, each of the signal level detecting means supplies the detection signal to the control signal generating means of another channel for gain reduction and to the control signal generating means of its own channel for gain increase. .

[0007]

According to the first aspect of the present invention, the string vibration detecting means provided for each of the plurality of strings is provided with a vibration of a string other than the corresponding string,
That is, a crosstalk signal is generated. Among such string vibration detection means, for those corresponding to a specific string,
The simulated crosstalk signal generation means generates a simulated crosstalk signal that simulates a crosstalk signal generated by another string. Since the canceling means cancels the simulated crosstalk signal from the output signal of the string signal detecting means corresponding to a specific string, it is possible to generate a vibration detecting signal independent of each string.

According to the second aspect of the present invention, the levels of the plurality of musical tone signals supplied to the plurality of input terminals are detected by the level detecting means in the corresponding channels. The level detection signal of the level detecting means is supplied to the control signal generating means provided for each channel. The detection signal of each signal level detecting means is supplied to the control signal generating means of another channel for gain reduction. Therefore, when a plurality of musical tone signal sources simultaneously output musical tone signals, a certain channel is , The gain is reduced according to the signal levels of other channels, and the gain is increased according to the signal level of its own channel. Also,
When the musical tone signal source outputs a musical tone signal for a certain channel alone, the gains of the other channels are reduced, and the detection signals for reducing the gain are not supplied from the level detecting means of those other channels. Therefore, the output signal obtained by synthesizing the output signals from each of these channels works to reduce the noise of the channel being played in the case of a polyphonic performance, and further, in the case of a polyphonic performance and a single-tone performance, it is audible. , And output signals of substantially the same level.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment is shown in FIGS. In this embodiment, the present invention is applied to an electric guitar and has six strings 1 to 6 as shown in FIG. These strings 1
Piezoelectric pickups 7 to 12, for example, are provided on the to 6 as string vibration detecting means.

The output signals of the pickups 7 to 12 are supplied to the canceling means, for example, the addition terminals of the adders 13 to 18.

The output signal of the pickup 7 is supplied to a simulated crosstalk signal generating means, for example, an adaptive filter 19, and the output signal of the adaptive filter 19 is added to the adder 1.
4 is supplied to the subtraction terminal. Similarly pickup 8
Output signal is supplied to the adaptive filters 20 and 21,
The output signal of the adaptive filter 20 is supplied to the subtraction terminal of the adder 13, and the output signal of the adaptive filter 21 is supplied to the subtraction terminal of the adder 15.

The output signal of the pickup 9 is supplied to the adaptive filters 22 and 23, and the output signal of the adaptive filter 22 is applied to the subtraction terminal of the adder 14 and the adaptive filter 23.
The output signals of are respectively supplied to the subtraction terminals of the adder 16. The output signal of the pickup 10 is supplied to the adaptive filters 24 and 25, and the output signal of the adaptive filter 24 is supplied to the subtraction terminal of the adder 15 and the adaptive filter 25.
The output signals of are respectively supplied to the subtraction terminals of the adder 17.

The output signal of the pickup 11 is supplied to the adaptive filters 26 and 27, and the output signal of the adaptive filter 26 is supplied to the subtraction terminal of the adder 16 and the adaptive filter 27.
The output signals of are respectively supplied to the subtraction terminals of the adder 18. The output signal of the pickup 12 is supplied to the adaptive filter 28 and is supplied to the subtraction terminal of the adder 17.

In this way, each of the adaptive filters 19 to 28 is
The output signals of are respectively supplied to the subtraction terminals of the adders to which the output signals of the pickups of the adjacent strings are supplied. The output signals of the pickups 7 to 12 are actually digitized by the A / D converter, and then added to the adders 13 to 18 and the adaptive filters 19 to 2 respectively.
8, but the A / D converter is not shown in FIG. 1 to simplify the drawing.

Each of the adaptive filters 19 to 28 supplies an output signal to the adder to which the output side of each adaptive filter 19 to 28 is connected by the vibration of the string corresponding to the pickup connected to its input side. It is set so as to generate a simulated crosstalk signal that simulates the crosstalk signal generated in the pickup being operated.

For example, as shown in FIG. 2, in the case of the adaptive filter 20, the output signal of the adder 13 is input to its adjustment terminal and the string 2 is vibrated while the string 1 is not vibrated. Adaptive so that the signal generated by the pickup 7 (crosstalk signal) and the output signal of the adaptive filter 20 (simulated crosstalk signal) have the same value, that is, the output signal of the adder 13 becomes 0. Adjust the mold filter 20. The other adaptive filters 19, 21 to 28 are similarly adjusted. As an algorithm for adjusting the adaptive filter 20, for example, a least mean square algorithm (LMS) or the like may be used.

In this way, each of the adaptive filters 19 to 28 is
Since the crosstalk signal is detected by the pickups 7 and 9 and is supplied to the adders 13 and 15 when, for example, only the string 2 is played, at the same time, the adaptive filters 20 and 21 respectively simulate the crosstalk. Since the talk signals are generated and supplied to the adders 13 and 15, these crosstalk signals are canceled by the simulated crosstalk signal and the adders 13 and 15. Therefore, the adder 1
No crosstalk signal is output from 3 and 15. Although the above description relates to the case where one string is played, the crosstalk signals are similarly canceled when a plurality of strings are played simultaneously.

In the above embodiment, the adaptive filters 19 to 28 are provided so as to cancel only the crosstalk from the adjacent strings to the pickup, but the strings other than the adjacent strings are
For example, in the case of the pickup 7, crosstalk from the strings 3 to 6 other than the string 2 may occur. If these are also canceled, the circuit configuration becomes slightly complicated, but the pickups 9 to 12 are newly adapted. Filters may be provided and the output signals of these adaptive filters may be input to the subtraction terminal of the adder 13. Of course, in this case, each of the added adaptive filters is adjusted so as to generate a simulated crosstalk signal simulating the crosstalk signal generated by the strings 3 to 6 in the pickup 7.

FIG. 3 shows a second embodiment. In this embodiment also, the present invention is applied to an electric guitar, and pickups 30 to 35, which are musical tone signal sources, are provided for six strings (not shown). Each pickup 3
The output signals of 0 to 35 are supplied to the signal processing devices 36 to 41, respectively.

Since the signal processing devices 36 to 41 have the same structure, only the signal processing device 36 will be described in detail. The signal processing device 36 has a distortion circuit 42 that adds an effect, for example, distortion to the output signal from the pickup 30. The output signal of the distortion circuit 42 is supplied to the gain control means, for example, the multiplier 43, and the output signal of the multiplier 43 is output as the output signal of the signal processing device 36. With this distortion circuit 42 and multiplier 43,
The channel is configured. Although not shown, the output signals of the signal processing devices 36 to 41 are combined by a combiner and input to, for example, an audio device.

From the middle stage of the distortion circuit 42,
The signal during the distortion processing is taken out and supplied to the level detecting means, for example, the envelope detecting circuit 44,
The signal level during the distortion process is detected. The signal level during distortion processing is detected because the signal level after distortion processing is too high, and the signal before distortion processing is
This is because the signal level is too small to detect an envelope signal of an appropriate level.

The output signal of the envelope detection circuit 44 is
For example, when the pickup 30 generates an output signal of the maximum level, it generates an output signal of, for example, 1. This output signal is multiplied by the coefficient α in the multiplier 45,
It is supplied to one addition terminal of the adder 46. The output signal of the envelope detection circuit 44 is supplied to the other signal processing devices 37 to 41.

The output signals from the envelope detection circuits of the other signal processing devices 37 to 41 are supplied to the multipliers 47 to 51 and multiplied by the coefficient β, respectively. The output signals of the multipliers 47 to 51 are added by the adder 52 and supplied to the subtraction terminal of the adder 46. An initial level, for example, 1 is supplied to the other addition terminal of the adder 46, and the output signal of the adder 46 is supplied to the multiplier 4
3 is supplied as a multiplication coefficient to the distortion circuit 4
2 Adjust the output signal level. These multipliers 43, 4
5, 47 to 51 and the adders 46 and 52 constitute the control signal generating means.

If all the strings are simultaneously played and the envelope detection circuit 44 of each of the signal processing devices 36 to 41 generates a level detection signal A (0≤A≤1), for example.
From the adder 46 to the multiplier 43 of the signal processing device 36,
A multiplication factor of (1 + A (α-5β)) is provided. Also, when three strings are played, for example, pickups 30, 3
1, 32 generate output signals, and signal processing devices 36, 3
If the envelope detection circuits 44 of 7 and 38 generate the level detection signal A, for example, (1 + A (α-2β)) is added to the multiplier 43 from the adder 46 of the signal processing device 36.
When the envelope detection circuit 44 of the signal processing device 36 generates, for example, the level signal A, the multiplication coefficient of is supplied to the multiplier 43 from the adder 46 of the signal processing device 36 to the multiplier 43. , (1 + Aα) multiplication coefficients are supplied.

When the multiplication coefficient of (1 + A (α-5β)) is supplied from the adder 46 of the signal processing device 36 to the multiplier 43, the levels of the output signals output from all the signal processing devices 36 to 41 are changed. They are almost equal to each other, and their combined value becomes equal to the output level of the multiplier 43 when the multiplication coefficient of (1 + Aα) when playing a single note is supplied to the multiplier 43, and (1 + A (α-2β)) When the multiplication coefficient is supplied, the levels of the output signals output from the signal processing devices 36 to 38 are almost the same in terms of hearing, and the combined value of these is multiplied by the multiplication coefficient of (1 + Aα) when a single note is played. The values of α and β are commonly selected for various values of A so that the output level of the multiplier 43 when supplied to the amplifier 43 is substantially equal to the auditory sense. As the values of α and β, for example, 0.2 is used as a result of the experiment.

For example, when all the strings are played, a coefficient 1/6 is supplied to the multiplier 43 of each of the signal processing devices 36 to 41, and five, four, three and two strings are played. When the string is played, the multiplier 43 of the signal processing device corresponding to the string played is supplied with the coefficients 1/5, 1/4, and 1/31/2, respectively, and when one string is played, the string is played. It is also conceivable to supply a factor of 1 to the multiplier 43 of the signal processing device corresponding to the string. However, with such a configuration, a detection circuit for how many strings are played must be provided in each of the signal processing devices 36 to 41, which makes the circuit configuration very complicated. On the other hand, if this embodiment is adopted, the circuit configuration becomes simple.

In this embodiment, as is apparent from FIG. 3, the signal processing device 36 is supplied with the envelope detection signals from the envelope detection circuits of the signal processing devices 37 to 41, and in the signal processing device 37, the signal processing device 36 is supplied. , 38
The envelope detection signals from the envelope detection circuits 41 to 41 are supplied. That is, each of the signal processing devices 36 to 4
The envelope detection signals input to 1 are not all the same, which makes the wiring work (program in the case of software) complicated. This point is improved by the third embodiment shown in FIG.

In the third embodiment, each signal processing device 36a.
Through 41a, the envelope detection signal of the envelope detection circuit 44 is processed by the multiplier 45a by the coefficient (α + β).
Is multiplied and then supplied to the adder 46. on the other hand,
The envelope detection signals of the signal processing devices 36a to 41a are multiplied by the coefficient β in the multipliers 53 to 58, added by the adder 60, and then clipped by the clip circuit 6.
The maximum value is limited to a predetermined value by 1 and then supplied to the adder 46 of each of the signal processing devices 36a to 41a.

With this configuration, each signal processing device 3
Since it is only necessary to supply a signal from the clip circuit 61 to 6a to 41a, the wiring work becomes easy. The clip circuit 61 is provided in order to prevent the signal level from decreasing too much when a large number of strings are played simultaneously. For example, in the embodiment shown in FIG. It can be provided on the output side of 52.

Although the present invention is applied to the electric guitar in the second and third embodiments, the present invention is not limited to the electric guitar, and may be applied to other electric string musical instruments and other electronic musical instruments. It can be carried out. In the above embodiment, the effect adding device (distortion circuit 42) is provided for each channel, but only the volume control may be performed without providing the effect adding device. However, in this case, the envelope detection circuit 44 directly detects the level of the input signal.

Further, when the distortion circuit 42 is not provided, it is not necessary that the volume of a single tone is equal to the volume of a complex tone, and in such a case, appropriate coefficients α and β are appropriately set by experiments. do it.

As described above, according to the second and third embodiments, since it works to suppress the gain of channels other than the channel which is producing sound, for example, when producing a single tone, By suppressing the gain, the noise of the channels that are not sounding is suppressed, and the effect is great especially in the case where the high gain distortion circuit is provided, and the distortion effect is added to each conventional channel. Compared to, a very clear musical tone signal with less noise can be obtained.

Further, these embodiments can be set even in a state where there is no sound volume difference between the case of playing a plurality of notes and the case of playing a single note. This makes it easy to play without any unnatural volume difference.

[0034]

As described above, according to the first aspect of the present invention,
A simulated crosstalk signal generation means generates a simulated crosstalk signal simulating a crosstalk signal generated by another string with respect to the string vibration detection means corresponding to the specific string, and the simulated crosstalk signal generation means generates the simulated crosstalk signal. Since the canceling means cancels the output signal of the detecting means, the occurrence of crosstalk can be prevented.

Further, according to the second aspect of the present invention, the level detection signals of the level detection means for detecting the signal level of each channel are supplied to the control signal generation means provided for each channel, respectively. The level detection signals of the channels are used for increasing the gain, and the level detection signals of the other channels are used for decreasing the gain, so no matter how many tone signal sources generate the tone signals, The level of the combined output signal of the output signals from the respective channels is substantially constant. Furthermore, since the gains of channels other than the ones that are sounding are reduced, the noises generated from those channels that are not sounding are suppressed, so that a clear musical tone signal with few noise components can be generated.

[Brief description of drawings]

FIG. 1 is a block diagram of a first embodiment of the present invention.

FIG. 2 is an explanatory diagram of an adaptive filter adjustment method according to the first embodiment.

FIG. 3 is a block diagram of the second embodiment.

FIG. 4 is a block diagram of the third embodiment.

[Explanation of symbols]

7 to 12 pickup (string vibration detecting means) 13 to 18 adder (cancellation means) 19 to 27 adaptive filter (simulated crosstalk signal generating means) 30 to 31 pickup (tone signal source) 42 distortion circuit (effect adding means) 43 multiplier (gain control means) 44 envelope detection circuit (level detection means) 45 45a 47 to 51 47a to 51a 53
To 58 multiplier (control signal generating means) 46 52 60 adder (control signal generating means) 61 clip circuit (control signal generating means)

Claims (2)

[Claims] 1. A plurality of string vibration detecting means which is provided for each of a plurality of strings and mainly detects the vibration of the corresponding string, and another string for the string vibration detecting means corresponding to the particular string. A simulated crosstalk signal generating means for generating a simulated crosstalk signal simulating the generated crosstalk signal, and a canceling means for canceling the simulated crosstalk signal from the output signal of the string signal detecting means corresponding to the specific string. , Equipped electric stringed instrument. 2. A plurality of input terminals for inputting musical tone signals to a plurality of channels respectively, and a plurality of gain control means provided for each of the plurality of channels for controlling the gain of the musical tone signals input to these input terminals, A plurality of signal level detecting means for detecting a signal level in each of the channels, and a gain control signal for the gain controlling means, which is provided for each of the channels, and generates a gain control signal for the gain control means in accordance with a detection signal of the signal level detecting means A plurality of control signal generating means, each of the signal level detecting means supplies the detection signal to the control signal generating means of another channel for gain reduction, and the control signal generating means of its own channel. A volume correction device, which is supplied to a device for increasing gain.