Electronic acoustic device

Abstract

To provide an acoustic device that satisfies a request to listen to sharp sound, whose sound quality not depending on higher harmonics, is comfortable without stimulating ears even in a high band, and reduces annoyance to the neighborhood by reducing noise pollution.SOLUTION: An acoustic device increases voice volume by a voice volume correction function by digital processing, and outputs powerful and sharp sound. In addition, the acoustic device generates a component having a slightly high frequency and a component having a slightly low frequency only in each cycle from an input signal of the acoustic device, by mixing outputs, mixes them with zero wavelength error and zero phase error, and outputs sound that is pleasant to an ear as if it were a chord. Further, the acoustic device reduces noise pollution by deforming a ratio of a positive and a negative time width of a sound pressure curve of the sound emitted from a speaker of the acoustic device to an arbitrary ratio and making glass, a wall, and a floor unable to smoothly vibrate.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an electronic acoustic device.

Background Art

[0002] The sound of a conventional electronic acoustic device is a dull sound lacking clarity, such as a muffled or stuffy sound, and there have been many voices seeking a crisp sound.

[0003] The sound of a conventional electronic acoustic device is a shrill sound that stimulates the ears, and the sounds in the mid- to high-frequency ranges are not very popular.

[0004] When the vibration of the sound output from the speaker of a conventional acoustic device is applied to a glass plate, the glass plate vibrates smoothly, and as a result, secondary radiation is emitted outdoors, causing noise pollution. The part radiated indoors is reflected, deteriorating the tone quality.

Summary of the Invention

Problems to be Solved by the Invention

[0005] As Problem 1, when an active element having non-linear characteristics is used for signal amplification, odd-order harmonics are always superimposed more or less as shown in FIG. 4. When the peak value becomes 38, the output energy (the area of the waveform of the output signal, hereinafter referred to as the volume) should become the curve 32 where the volume can be ensured, but the actual output waveform curve becomes 31, and since the volume is small, the speaker can only be driven weakly, resulting in a muffled or stuffy and unclear sound.

[0006] As Problem 2, when a clean sine wave is reproduced by a speaker, a screeching sound that stimulates the ears is produced. Therefore, conventional electronic audio devices superimposed a large number of harmonics on a sound close to this sine wave by the same principle as described above and distorted the waveform so as not to stimulate the ears. However, high frequencies become difficult to reproduce due to problems with the frequency characteristics of the audio device and the frequency characteristics of the speaker. High frequencies beyond the midrange result in a signal with a shape close to a sine wave being supplied to and reproduced by the speaker, thus becoming a sound that stimulates the ears.

[0007] As Problem 3, a glass plate vibrates in a resonant manner because the ratio of the temporal width of the high-pressure part of the applied sound vibration to the ratio of the temporal width of the low-pressure part is the same. Means for Solving the Problems

[0008] The present invention was made to solve the problems. The ratio of the temporal width of the positive voltage part and the ratio of the temporal width of the negative voltage part of the electrical output signal of the audio device are deformed from the same ratio to an arbitrary ratio, and further, an audio device characterized by adding a volume correction function having a function of adjusting the volume of the electrical output signal. Effects of the Invention

[0009] When the strings of a stringed instrument such as a guitar are plucked with a finger, taking 1000 Hz as an example, it stays on the left side for 0.5 milliseconds and also stays on the right side for the same 0.5 milliseconds. Since the left and right stay times are the same, it vibrates well, generates a pleasant sound, and the afterglow can also be enjoyed. This is common to all substances in nature. When a force such as a strike is applied, the time ratio of the indented part to the part that returns to the front side is the same. However, since the present invention changes this time ratio, it becomes a strange sound not found in nature, a sound that even glass cannot vibrate well, and as a result, it becomes a pleasant sound to the ears. Generally, the phenomenon that sound becomes a harmony should not occur with a single input signal, but from the listening experience, this expression feels the closest.

[0010] Generally, when it comes to the phenomenon of sound becoming a chord, it is easy to assume equal frequency distances such as 900 Hz and 1100 Hz relative to 1000 Hz. However, in the present invention, signals with equal wavelength distances such as 1000 Hz ÷ 1.1 = 909.1 Hz and 1000 Hz ÷ 0.9 = 1111.1 Hz are generated, mixed, and output. Therefore, the phases of the higher-frequency part and the lower-frequency part should not be aligned, but they are aligned. Furthermore, when observing the output waveform with an oscilloscope, the same frequency components as the input signal cannot be found. However, from the listening experience, it seems to be exactly the same as the input frequency, and it is discovered that it becomes a pleasant sound for the ears, similar to a chord, and the present invention is proposed.

[0011] Due to the vibration of the sound output from the speaker of the acoustic device, the vibration of glass, walls, and floors cannot be made smooth, so the vibration stroke of glass, walls, and floors becomes small, the sound emitted outdoors becomes small, and noise pollution can be reduced. Furthermore, since the sound reflected indoors becomes small, the tone quality becomes even better.

[0012] In the present invention, the high-Q waveform shaping coils 26a and 26b in FIG. 3 correct and restore the reduction in volume generated by the active element with non-linearity. As a result, the stuffy feeling and the fuzzy feeling are wiped out, and it becomes a crisp and powerful sound, satisfying the requirements of users who desire a crisp sound. In particular, the sound of percussion instruments and fast-tempo songs have become more comfortable.

[0013] When processing digitally, since there is no equivalent to the high-Q waveform shaping coils 26a and 26b in FIG. 3 added, the volume is not corrected and the stuffy feeling and the fuzzy feeling cannot be completely wiped out. Therefore, according to the preference of the user, the volume correction function of claim 2 is added so that the volume can be adjusted, and the strength of the sound can be adjusted, thus satisfying the requirements of many users who "want to hear a sound with good articulation".

Brief Description of the Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Modes for Carrying Out the Invention

[0015] Figure 2 is a diagram for explaining the operating principle of 26a and 26b in the waveform shaping coil with a high Q represented by 2πfL÷R (hereinafter referred to as Q). However, since the actual input waveform curve 8 is current and the dotted output waveform curve 13 is voltage, they cannot actually be displayed identically. However, for understanding the operation, it is necessary to compare them, so they are displayed identically.

[0016] As a method for analog processing, for example, the following are possible. Figure 3 is a circuit example configured for problem-solving, and the explanation of Figure 2, which is the operating principle diagram of 26a and 26b in the waveform shaping coil, will be continued.

[0017] In the first-stage tube 23 of Figure 3, a signal curve 8 containing a large number of odd harmonics is created so that the difference between the positive voltage 11 and the negative voltage 12 in Figure 2 becomes large. When the high-Q waveform shaping coil 26a and 26b in Figure 3 is energized, In this waveform shaping coil 26a and 26b, In the increasing section of the energizing current from 18 to 19 and then to 20, a positive voltage like 16 is induced, and in the decreasing section of the energizing current from 20 to 21 and then to 22, a negative voltage like 17 is induced. Of course, if the start and end of the coil winding are reversed, the reverse voltage will be generated, but the explanation will become complicated, so the explanation will continue under this condition.

[0018] Since the height of the voltage induced in the high-Q waveform shaping coil 26a and 26b in Figure 3 is proportional to the change amount of the current, The sum of 11 and 12 in FIG. 2, which is the change amount in the current increase interval from 18 to 19 and then to 20 in FIG. 2, and When compared with the sum of 12 and 11 in FIG. 2, which is the change amount in the current decrease interval from 20 to 21 and then to 22 in FIG. 2, Since they are of the same magnitude, 16 and 17 in FIG. 2 should have the same value. Therefore, the voltage induced in 26a·26b of the waveform shaping coil in FIG. 3 should be the back electromotive force curve 13 in FIG. 2, which is a waveform obtained by moving the waveform of the energizing current curve 8 in FIG. 2 90 degrees to the left and further downward in the figure. However, the positive voltage 16 and the negative voltage 17 in FIG. 2 do not become the same because the coil has a resistance component. In a normal coil, it does not move much downward and is not much related to performance, nor does it move much to the left, so it is often not practical.

[0019] To solve this problem, the coil should be able to increase Q by utilizing the characteristic that the inductance increases when the energizing current is reduced. When the resistance values of the bias resistors 27a·27b in FIG. 3 of the driver tubes 25a·25b in FIG. 3 are set large so that a small current of one-tenth to one-fortieth of the rated current flows through the coil, although it is not perfect, waveform processing was successful.

[0020] As a method to increase Q, there is also a method of winding the two coils 26a·26b of the waveform shaping coil in FIG. 3 in reverse phase around one iron core. If it is formed in a shape where the primary side of the push-pull output transformer is divided into two systems and the secondary side coil is removed, it can be used as a waveform shaping coil with better performance.

[0021] As a result, since Q is not very large, 16 and 17 of the induced voltage in FIG. 2 do not become exactly the same value. However, the waveform of the induced voltage curve 13 in FIG. 2 becomes a shape that moves parallel downward. The time width 9 on the positive side of the input waveform in FIG. 2 is reduced to 14, and the time width 10 of the negative voltage in FIG. 2 is expanded to 15, and the time ratio of the positive voltage and the negative voltage can be changed. The ratio of the temporal width of the positive voltage portion and the ratio of the temporal width of the negative voltage portion of the electrical output signal of the audio device could be deformed from the same ratio to an arbitrary ratio.

[0022] Using the analog method of the present invention from 0016 to 0021, four audio amplifiers with four types of deformation amounts 7 in FIG. 1 were manufactured, and music signals were input and auditioned. The first unit did not measure the deformation amount 7 in FIG. 1. The second unit set the deformation amount 7 in FIG. 1 to approximately 2.5%. The third unit set the deformation amount 7 in FIG. 1 to approximately 1.7%. The fourth unit set the deformation amount 7 in FIG. 1 to approximately 5%.

[0023] It was expected that the fourth unit with a large deformation amount 7 in FIG. 1 would have a greater effect than the third unit with a small deformation amount 7 in FIG. 1, but there did not seem to be much difference in tone quality. Thus, it is thought that the deformation amount 7 in FIG. 1 will exhibit an effect as long as there is a certain amount, and there is no need to make it particularly large. As a result, all four units had good tone quality, good articulation, were powerful, and the sound leaking to the outside was small, reducing noise pollution.

[0024] When a vacuum tube amplifier performs single amplification, a lot of odd-order harmonics are generated in the power amplification section, resulting in a small volume, weak sound, and unclear sound. Therefore, as a countermeasure, all units from the first unit to the fourth unit are push-pull.

[0025] FIG. 4 is a figure slightly emphasized to easily understand the waveform with superimposed harmonics. When an odd-order harmonic curve 30 with a frequency three times that of the input signal curve 29 is superimposed, Since the peak value 38 of the output signal curve 31 becomes the value obtained by adding the peak value 36 of the harmonic curve 30 to the peak value 37 of the input signal curve 29, Normally, it should have a waveform with an area like the curve 32 where the volume is ensured. However, in the odd harmonic intervals 34, energy is added, while in intervals 33 and 35, it is added in the opposite phase, and since the peak value becomes higher, the area of the waveform of the output signal curve 31 is significantly smaller compared to the waveform of the curve 32 where the volume is ensured. Therefore, The volume of the sound becomes weak, the crispness deteriorates, and it becomes a soft and fluffy sound.

[0026] The desire of enthusiasts for a long time to "want to hear a crisp sound" has been strong. Some experts say that "improving the damping coefficient will improve the crispness." There are also enthusiasts who are frantically improving the damping coefficient, but in reality, there is little effect. As one of the methods to fulfill the requirements of these enthusiasts, the volume correction function of claim 2 is proposed.

[0027] In the invention according to the analog circuit of claim 1, the high-Q wave shaping coils 26a and 26b in FIG. 3 can recover the reduced volume to some extent, so the timbre becomes quite good. However, when processed digitally, since a high-Q wave shaping coil is not added, the timbre is inferior to that of the analog processing audio device. Therefore, a patent for the volume correction function is applied for in claim 2, and it is added when processed digitally.

[0028] FIG. 5 is a diagram that slightly emphasizes to make it easier to understand the principle of the volume correction of claim 2. Detect the 0V of the input signal and confirm the time width until the next 0V. Dividing that width into four equal parts gives the intervals 42, 43, 44, and 45 of the volume correction curve. Since the maximum volume correction value 46 has a significant impact on the timbre, it can be adjusted freely to some extent by the user to suit the user's preference. In 42 of the volume correction interval 1 and 44 of the volume correction interval 3, starting from 0V at the beginning of the interval and proportionally increasing so that the end of the interval becomes the maximum volume correction value 46. In the volume correction interval 2 at 43 and the volume correction interval 4 at 45, a volume correction curve 40 is created such that the start of the interval is set to the maximum volume correction value 46 and the end of the interval is proportionally decreased to 0V.

[0029] When the volume correction curve 40 is added to the input signal curve 39, an output signal curve 41 is obtained. This curve corrects the output curve 31 of the harmonic superposition curve in Fig. 5 and approaches the curve 32 that can ensure the volume in the case of the peak value 38. Although strictly speaking, the corrected position and amount seem different, in the following 0030 - 0031, only a simple method is used where the positive voltage side waveform appears to be in the shape of a pot lying down. However, when actually manufacturing and auditioning a prototype, no difference was felt, and it seems that the area of the corrected waveform is important and there is no need to be particular about the shape.

[0030] Using a special vacuum tube and gently limiting the rise of the peak value, When a prototype amplifier with the positive voltage side waveform deformed into the shape of a pot lying down was manufactured and auditioned, it produced a very powerful sound. As a result, the mid - range and high - range lost their roundness and softness and became the so - called bad sound. The power of the bass is outstanding. The No. 3 machine is the one that has undergone the processing of claim 1. The timbre of the mid - range and high - range has become very good, with good articulation and strength. Among the amplifiers owned by the applicant, the sound is the best. With this prototype, the applicant recognized the magnitude of the influence of volume correction on the timbre and is particularly applying for a patent as claim 2.

[0031] At this time, for the No. 3 machine, although the timbre has improved, the power of the bass has decreased. Before the processing of claim 1, the timbre was not good, but it has a strange sound that makes people want to listen to it again despite the bad timbre. So that it can be switched and used, For the waveform shaping coils 26a and 26b in Fig. 3, instead of using coils, a single - output transformer is used to reduce the primary - side current. When using a resistor with a large resistance value for the terminal resistance of the secondary coil, Q increases, so the deformation of 7 in Fig. 1 occurs and the sound quality improves, When using a resistor with a small resistance value for the terminal resistance of the secondary coil, since Q decreases, the deformation of 7 in Fig. 1 does not occur, so a powerful bass can be enjoyed. Therefore, if it is switched and used according to the track and the mood of the day, it will become a comfortable audio device. However, it should be noted that the powerful bass cannot prevent outdoor leakage.

[0032] As a method of digital processing, a music playback device having an input section, a sampling section, a first-in first-out memory section (hereinafter referred to as a buffer), a volume correction section, a polarity confirmation section, an arithmetic section, a playback section, and a conversion section is created.

[0033] In the input section, a music signal is read, sampled by the sampling section with a highly accurate sampling clock, and written into the buffer in a first-in manner.

[0034] The signal read out from the buffer first is corrected with the volume shown by the above 0028 to 0029 as a correction value and sent to the polarity confirmation section.

[0035] The polarity confirmation section confirms the positive and negative polarities, If it is a positive voltage, when the signal is sent to the signal playback section with a playback clock shorter than the basic clock, the positive voltage portion of the sent signal becomes shorter in time interval by the amount of 7 in Fig. 1 due to the time difference between the sampling clock and the playback clock, and the temporal width of the positive voltage portion becomes as short as 5, If it is a negative voltage, when the signal is sent to the signal playback section with a playback clock longer than the basic clock, the negative voltage portion of the sent signal becomes longer in time interval by the amount of 7 in Fig. 1 due to the time difference between the sampling clock and the playback clock, and the temporal width of the positive voltage portion obtains 6, and the signal is sent to the signal playback section.

[0036] At this time, similar to the above 0031, when you want to hear powerful sounds depending on the track, you can use a changeover switch to switch so that the sampling clock used for sampling, instead of the playback clock, can be used for the playback clock. When switched, you can enjoy powerful bass sounds.

[0037] In the signal reproduction unit, a positive voltage with a short wavelength and a negative voltage with a long wavelength are combined and sent to the signal conversion unit.

[0038] In the signal conversion unit that receives this signal, the output device determines whether it is an analog signal or USB. In the case of analog output, an output signal for a digital-to-analog converter is created, and in the case of USB output, a USB signal is created and output, creating a music playback device having the function of outputting.

[0039] Perform the processing from 0032 to 0037, and further use a digital-to-analog converter to perform analog output. Fabricate a dedicated IC chip for performing this series of processing, and if it is added to general electronic audio devices such as radios, televisions, stereos, karaokes, and electronic musical instruments, it can easily be made to have a good sound quality with a noise reduction function.

[0040] As described above, according to the present invention, clear, powerful, and comfortable music reminiscent of harmony can be enjoyed. Furthermore, since the volume of the sound leaking outdoors is reduced, concern for the neighborhood can be reduced, and a comfortable audio device can be provided.

Explanation of Signs

[0041] 1: Electric signal curve output from a conventional audio device 2: Temporal width of the positive voltage portion of the conventional electric signal curve 1 3: Temporal width of the negative voltage portion of the conventional electric signal curve 1 4: Electric signal curve deformed and processed according to the present invention 5: Temporal width of the positive voltage portion of the electric signal curve 4 deformed and processed according to the present invention 6: Temporal width of the negative voltage portion of the electric signal curve 4 deformed and processed according to the present invention 7: Amount of deformation when the temporal width of an electrical signal is processed 8: Current curve applied to the waveform shaping coils 26a and 26b in Fig. 3 9: Temporal width of the peak portion of the current curve 8 10: Temporal width of the trough portion of the current curve 8 11: Maximum value of the change in the current applied to the peak portion of the current curve 8 12: Maximum value of the change in the current applied to the trough portion of the current curve 8 13: Theoretical back electromotive force voltage curve induced in the waveform shaping coils 26a and 26b in Fig. 3 14: Temporal width of the peak portion of the back electromotive force voltage curve 13 15: Temporal width of the trough portion of the back electromotive force voltage curve 13 16: Maximum induced voltage value of the peak portion of the back electromotive force voltage curve 13 17: Maximum induced voltage value of the trough portion of the back electromotive force voltage curve 13 18: Minimum current point of the current curve 8 19: Point where the current increase interval of the current curve 8 passes 20: Maximum current point of the current curve 8 21: Point where the current decrease interval of the current curve 8 passes 22: Minimum current point of the current curve 8 23: First-stage vacuum tube that generates a large number of odd harmonics 24: Phase inversion vacuum tube 25a, 25b: Drive vacuum tubes 26a, 26b: Waveform shaping coils 27a, 27b: Bias resistors 28a, 28b: Power amplification vacuum tubes 29: Input signal 30: Third harmonic 31: Output signal 32: Waveform necessary to ensure volume 33: Negative voltage interval of the third harmonic 34: Positive voltage interval of the third harmonic 35: Negative voltage interval of the third harmonic 36: Third harmonic peak value 37: Input signal peak value 38: Output signal peak value 39: Input signal 40: Volume correction curve 41: Output signal 42: Volume correction curve section 1 43: Volume correction curve section 2 44: Volume correction curve section 3 45: Volume correction curve section 4 46: Maximum volume correction value

Claims

1. An audio device, characterized in that it is possible to deform the ratio of the temporal width of the positive voltage portion and the ratio of the temporal width of the negative voltage portion of the electrical output signal of the audio device from the same ratio to an arbitrary ratio by an electric circuit.

2. The audio device according to claim 1, further comprising a volume correction function having a function of adjusting the volume of the electrical output signal in the audio device.

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