RU2113069C1 - Method and device for converting electric signals into sound waves - Google Patents

Abstract

FIELD: loudspeakers in which acoustic waves are produced from electric oscillations and acoustic power is radiated into environment. SUBSTANCE: audio-range electric signal is submitted as digital signal in parallel N-bit code, square-pulse trains synchronous with binary trains of respective digital-signal bits are shaped from each of N bits of digital signal, and acoustic waves radiating N trains of acoustic pulse signals are excited by shaped signals of N acoustic emitters. Acoustic-signal pulse power for length equal to digital-signal sampling frequency period is calculated for each acoustic radiator using definite dependence. EFFECT: characteristics of reproduced sound frequencies throughout entire audio-frequency range. 11 cl, 9 dwg

Description

 The invention relates to transducers designed to receive acoustic waves from electrical vibrations and radiation of acoustic power into the environment, and more particularly to loudspeakers.

 Known methods for converting electrical signals into sound waves and implementing devices containing various means of converting electrical signals into sound (see "Acoustics": Reference. M: Radio and communications, 1989. S. 135-146; "Electrodynamic loudspeakers." Aldoshina I.A. M.: Radio and communication, 1989, p. 225-263). The disadvantages of these known technical solutions include the non-uniformity of the amplitude-frequency characteristics, large distortions, the need to use additional acoustic means to improve these characteristics (see "Acoustics": Handbook. M.: Radio and Communications, 1989, pp. 147-158) . In addition, well-known loudspeakers and speakers cannot be matched with the electric signal of the sound range presented in digital form (hereinafter digital signal).

 A known method of converting electrical signals of the audio range into sound, in which the converted electrical signal of the audio range, presented as a digital signal in a parallel N-bit code, is converted into an analog signal, generate excitation signals of acoustic emitters and fed to acoustic emitters (application Germany N 4205037 Cl. H 04 R 1/32, 1993). It is also known a device for converting electrical signals into sound waves, comprising a plurality of acoustic emitters arranged in a ruler or matrix, to which an analog electrical signal of a sound range is supplied there. The disadvantages of the known method and device for converting electrical signals into sound waves include the non-uniformity of the amplitude-frequency characteristics, large distortions, design complexity, causing a high manufacturing cost.

 The objective of the invention is to provide a method and a device that implements it, providing the conversion of electrical signals of the audio range, presented in digital form, into sound waves.

 The technical result achieved in this case is to improve the quality of reproduced sound frequencies in the entire sound range.

The specified technical result is achieved by the fact that in the method of converting electrical signals into sound waves, in which the converted electrical signal of the sound range is represented as a digital signal in a parallel N-bit code and generating excitation signals of acoustic emitters, in accordance with the invention, the excitation signals of acoustic emitters form from each of the N digits of the received digital signal in the form of sequences of rectangular pulses synchronous with binary after the sequences of the corresponding digits of the digital signal, formed by sequences of rectangular pulses using N acoustic emitters, form N sequences of acoustic pulse signals in which the pulse of the acoustic signal corresponds to the logical "1" of the digital signal, and the gap between the pulses of the acoustic signal corresponds to the logical "0" of the digital signal, while the pulse power of the acoustic signal for a duration equal to the period of the sampling frequency of the digital signal, each of N acoustic emitters are determined in accordance with the formula
P _i = P ₁ • 2 ^i-1 , (1)
Where
P ₁ is the acoustic pulse power of the first acoustic emitter excited by a sequence of rectangular pulses corresponding to the least significant digit of the digital signal;
P _i is the acoustic pulse power of the i-th acoustic emitter, i = 1. . . N, excited by a sequence of rectangular pulses corresponding to the i-th digit of a digital signal.

In this case, the sequences of rectangular pulses are preferably formed with intrapulse filling with signals with a frequency higher than the sampling frequency of the digital signal, in particular with the frequency of the intrapulse filling signal, determined by the formula
f = m • F, (2)
or according to the formula
f _i = m _i • F, (3)
Where
f is the frequency of the signal intrapulse filling sequences of rectangular pulses;
m, m _i are natural numbers;
F is the sampling frequency of the digital signal;
f _i is the frequency of the intra-pulse filling signal of the i-th sequence of rectangular pulses.

 The specified technical result is also achieved by the fact that the device for converting electrical signals into sound waves, containing N acoustic emitters having inputs of the excitation signal, in accordance with the invention contains a block generating excitation signals, the inputs of which are connected to the output of the digital signal source of the audio range in parallel N -digit code, the number N of acoustic emitters is equal to the number of bits of said digital signal, wherein each of the N acoustic emitters is nen with the possibility of emitting acoustic signals in which the pulse of the acoustic signal corresponds to the logical "1" of the digital signal, and the gap between the pulses of the acoustic signal corresponds to the logical "O" of the digital signal, the pulse power of the acoustic signal for a duration equal to the period of the sampling frequency of the digital signal is determined by formula (1), while the inputs of the excitation signal of each of the emitters from the 1st to the Nth are connected respectively to the outputs of the excitation signal generating unit, corresponding to E from the lowest digits of said digital signal Sr. sound range.

 The excitation signal generating unit preferably contains N formers, the inputs of which are connected respectively to the inputs from the 1st to the Nth excitation signal generating unit, and the outputs are connected to the outputs of the excitation signal generating unit, corresponding to the least significant digit from the mentioned digital audio signal.

 The excitation signal generating unit may also contain N shapers, N modulators and a generator, while the shaper inputs are connected respectively to the inputs from the 1st to the Nth excitation signal generating block, and the outputs are connected to the first modulator inputs, the outputs of which are connected to the block outputs generating excitation signals corresponding to the least significant bits of the digital audio signal of the sound range, the output of the generator is connected to the second inputs of the modulators.

 Also, the excitation signal generation block may contain N shapers, N modulators, a sampling frequency allocation block of the input digital signal and a multiplier generator, while the shaper inputs are connected respectively to the inputs from the 1st to the Nth excitation signal generating block, and the outputs are with the first inputs of modulators, the outputs of which are connected to the outputs of the block generating excitation signals corresponding to the bits from the lowest to oldest of the mentioned digital signal of the audio range, the inputs of the block are highlighted I digital input signal sampling frequency connected to the inputs from the 1st to N-th blocks forming the excitation signal, the output sampling frequency block allocation input digital signal coupled to input generatora- multiplier whose output is connected to second inputs of modulators.

 In addition, the excitation signal generating unit may contain N formers, N logical elements AND, and a generator, while the first inputs of the logical elements AND are connected respectively to the inputs from the 1st to the Nth block of generating excitation signals, the outputs of the logical elements AND are connected respectively to the inputs of the shapers, the outputs of which are connected to the outputs of the block for generating excitation signals corresponding to the bits from the lowest to oldest of the mentioned digital signal of the sound range, the output of the generator is connected with the second inputs of logic elements I.

In addition, at least one acoustic emitter can be made in the form of a group of acoustic emitters of lower power with a total power of this group of emitters equal to the power P _i mentioned at least one acoustic emitter.

Moreover, the said group of acoustic emitters with a total power of P _i may consist of 2 ^i-1 identical elementary emitters with a power of P ₁ .

 The invention is based on the following theoretical premises.

 To improve the quality of the recorded, reproduced and transmitted sound signal, as well as to simplify the reception and processing, as you know, the sound signal is converted to digital form, i.e. carry out its discretization in time and quantization by level, the characteristics of which are, respectively, the sampling frequency F and the digitization capacity of N.

 The digital signal has two levels: "0" - there is no signal and "1" - there is a signal.

With the digital method of representing an audio signal, the quantization bit determines the number of steps from the minimum to the maximum level of the analog signal, which is 2 ^N. For example, with 16-bit quantization, the number of “steps” is 2 ¹⁶ = 65536. From this it follows that the more “steps” (digits), the more accurately the sound signal is transmitted when it is converted from analog to digital and vice versa.

Another characteristic of the conversion is the sampling rate. According to Kotelnikov’s theorem, the sampling rate must be determined from the condition
F≥2 • F _max , (4)
Where
F _max - the maximum frequency of the converted signal.

 After conversion, the digital audio signal can be recorded on various media, repeatedly read from media, transmitted via communication lines, and to perform various processing. The main advantage of a digital audio signal is the absence of noise and signal distortion inherent in analogue methods of recording, reading, transmission and processing.

 The sound receiver is the organ of hearing - an analog device, so it is necessary to carry out the inverse conversion of the digital signal to analog. When the digital signal of the sound range is converted back to analog form using a digital-to-analog converter and the sound is obtained by means of devices for converting electrical signals into sound waves (loudspeakers), distortions occur. In this case, the loudspeakers introduce the most significant distortion of the audio signal.

In accordance with the invention, it is proposed to reproduce an audio signal also by “steps” using a “digital loudspeaker”. For this, it is necessary that the emitters of such a “digital loudspeaker” have two radiation states corresponding to the presence of a signal (“1” digital signal) and its absence (“0” digital signal). To obtain the above number of "steps" (2 ^N ), N acoustic emitters are required. Moreover, the power of acoustic emitters included in the "digital loudspeaker" is determined by the formula (1).

 After converting the digital signal into excitation signals and supplying these signals to acoustic emitters, the pulse train of the digital signal is converted into a sequence of acoustic pulses. In this case, synchronism between the mentioned pulse sequences, i.e. their temporal characteristics must match. It is also necessary to ensure the synchronism of the acoustic pulses of all acoustic emitters, as well as the synchronism of all bits of the digital signal with each other.

 As a result of the operation of the device for converting electrical signals into sound waves, the spatial addition of all acoustic waves emitted by the emitters occurs.

The total radiation power of the device converting electrical signals into sound waves is determined by the formula
P = P ₁ + ... + P _i + P _N , (5)
or
P = P ₁ + ... + P ₁ • 1 ^i-1 + P ₁ • 2 ^N-1 , (6)
The maximum power value corresponding to the case when all bits of the digital signal have a value of "1" is
P = P ₁ • (2 ^N - 1), (7)
The minimum power value corresponding to the case when all bits of the digital signal have a value of "0" is
P = 0
Intermediate values are determined by the ratios "0" and "1" in the digits of the digital signal.

From the above relations (5) - (8) it follows that the number of steps of the total acoustic signal will also be 2 ^N.

 Thus, digital-to-analog conversion of the digital audio signal into analog acoustic signals is carried out. In this case, the digital-to-analog converter and loudspeaker are the device itself for converting electrical signals into sound waves. That is, the need to use conversion devices and “analog speakers” is eliminated, and thereby their inherent disadvantages are eliminated.

 Since all emitters have the same principle of operation, which consists in switching between two states - the presence and absence of a signal, it is possible to implement a device for converting electrical signals into sound waves, in which emitters of higher power consist of emitters of lower power.

 In FIG. 1 is a structural diagram of a device for converting electrical signals into sound waves, made according to the invention: in FIG. 2 - 6 are structural diagrams of various embodiments of a block for generating excitation signals; in FIG. 7 is a schematic representation of the location options of acoustic emitters; in FIG. 8, 9 are signal diagrams illustrating the operation of the device for converting electrical signals into sound waves, made according to the invention.

As shown in FIG. 1, a device for converting electrical signals into sound waves, made in accordance with the invention, comprises an excitation signal generating unit 1 connected to a source of an electrical signal of a sound range presented in digital form (not shown), and emitters 2 ₁ ... 2 _N.

In FIG. 2 shows an embodiment of an excitation signal generating unit 1, which comprises formers 3 ₁ ... 3 _N whose inputs are connected respectively to the inputs from the 1st to the Nth excitation signal generating unit 1, and the outputs are connected to the outputs of the excitation signal generating unit corresponding to the least significant bits of the digital audio signal.

In FIG. 3 shows an embodiment of an excitation signal generating unit 1, which comprises formers 3 ₁ ... 3 _N , modulators 4 ₁ ... 4 _N and a generator 5, while the inputs of the formers 3 ₁ ... 3 _{N are} connected respectively to the inputs with 1 on the Nth block of generating excitation signals, and the outputs are with the first inputs of modulators 4 ₁ ... 4 _N , the outputs of which are connected to the outputs of the block of generating excitation signals corresponding to the bits from the lowest to oldest of the digital signal of the sound range mentioned, the generator output 5 connected to second inputs s modulators 4 ₁ ... 4 _N.

In FIG. 4 shows an embodiment of a block for generating excitation signals 1, which comprises shapers 3 ₁ ..3 _N , modulators 4 ₁ ... 4 _N , a block for extracting the sampling frequency of the input digital signal 6, and a generator-multiplier 7, while the inputs of the shapers 3 ₁ . .. 3 _{N are} connected respectively to the inputs from the 1st to the Nth block of generation of excitation signals, and the outputs are connected to the first inputs of modulators 4 ₁ ... 4 _N , the outputs of which are connected to the outputs of the block of formation of excitation signals corresponding to the bits from the lowest by the eldest mentioned qi a smooth audio signal, the inputs of the sampling frequency allocation block of the input digital signal 6 are connected to the inputs from the 1st to the Nth excitation signals generating block, the output of the sampling frequency allocation block of the input digital signal 6 is connected to the input of the generator-multiplier 7, the output of which is connected with second inputs of modulators 4 ₁ ... 4 _N.

In FIG. 5 shows an embodiment of a block for generating excitation signals 1, which comprises shapers 3 ₁ ..3 _N , logical elements AND 8 ₁ . ..8 _N and generator 5, while the first inputs of the logic elements AND 8 ₁ ... 8 _{N are} connected respectively to the inputs from the 1st to the Nth block of generating excitation signals 1, the outputs of the logic elements AND 8 ₁ ... 8 _{N are} connected respectively to the inputs of the drivers 3 ₁ ... 3 _N , the outputs of which are connected to the outputs of the excitation signal generating unit corresponding to the bits from the lowest to oldest of the mentioned digital signal of the audio range, the output of the generator 5 is connected to the second inputs of the logic elements AND 8 ₁ .. .8 _N.

As shown in FIG. 6, according to the invention, at least one acoustic emitter 2 ₁ ... 2 _N can be made in the form of a group of acoustic emitters 9 ₁ . . . 9 _{N of} lower power with the total power of this group of emitters equal to the power P _{i of the} said emitter, calculated by the formula (1).

 In FIG. 7 shows the location options of acoustic emitters.

In FIG. 8: U - electrical signals of the audio range in analog form; D ₁ . . .D ₄ - signals at the input of the excitation signal generation block corresponding to the digits from the 1st to the 4th digital signal; P ₁ ... P ₄ - acoustic radiation power of the emitters, respectively, from the 1st to the 4th; P is the total radiation power of the device for converting electrical signals into sound waves.

In FIG. 9: U - electrical signals of the audio range in analog form; D ₁ . . .D ₄ - signals at the input of the excitation signal generation block corresponding to the digits from the 1st to the 4th digital signal; U _f is the clock signal at the output of the generator 5; P ₁ ... P ₄ - acoustic radiation power of the emitters, respectively, from the 1st to the 4th; P is the total radiation power of a device for converting electrical signals into sound waves.

Shapers 3 ₁ . . .3 _N used in various embodiments of the invention are blocks for matching digital signal levels with excitation signals of acoustic emitters. The implementation of the shaper depends on the specific technological features of acoustic emitters and can be carried out on the basis of well-known circuitry solutions using various logical (digital) or analog elements.

 Multiplier generator 7 used in the embodiment of FIG. 4 is a block in which an increase (multiplication) of the input clock frequency occurs for its further use in the device. The generator-multiplier can be made on the basis of well-known circuitry solutions using various logical (digital) or analog elements.

 The sampling frequency allocation unit of the digital signal 6 used in the embodiment of FIG. 4 is a block in which the quantization frequency is extracted from the bits of a digital signal that are received at its inputs using known circuitry solutions using various logical (digital) elements. In this case, various control signals can be involved, coming together with a digital signal from a signal source or coming from outside, for example, from an external control system (not shown), such signals can be, for example, a synchronization frequency, a recording signal, various strobe signals, etc. d.

Modulation is the process of controlling one or more parameters of harmonic oscillation. The modulator (4 ₁ ... 4 _N ) used in the embodiment of FIG. 3 and 4, is a block in which the "filling" of the excitation signals of acoustic emitters with signals of the incoming clock frequency. Modulators can work as electronic keys. The modulator can be implemented on the basis of well-known circuitry solutions using various logical (digital) or analog elements.

 A device for converting electrical signals into sound waves works as follows.

The electrical signal U (for clarity, presented as a sawtooth signal with 16 steps in Fig. 8a) of the audio range, converted into a digital parallel N-bit code (D ₁ ... D ₄ in Fig. 8b ... 8d), enters the unit for generating excitation signals 1 (Fig. 1), in which the digital signal levels of the digits D ₁ ... D _N are matched (Figs. 8, 9 are shown for a four-digit signal) with the excitation levels of acoustic emitters 2 ₁ . . . 2 _N. The excitation signals of acoustic emitters are generated from each of the N bits of the received digital signal in the form of sequences of rectangular pulses synchronous with the binary sequences of the corresponding bits. The generated sequences of rectangular pulses using N acoustic emitters 2 ₁ ... 2 _N form N sequences of acoustic pulse signals in which the acoustic signal pulse corresponds to the logical "1" of the digital signal, and the gap between the acoustic signal pulses corresponds to the logical "0" of the digital signal, wherein the pulse power of the acoustic signal (P ₁ ... P ₄ in Fig. 8e ... 8i) of each of the N acoustic emitters is determined in accordance with formula (1). In the emitters 2 ₁ ... 2 _N there is a conversion of the excitation signals into sound waves. In this case, the sound waves emitted by the emitter 2 ₁ correspond to the least significant digit of the digital signal D ₁ , the sound waves emitted by the emitter 2 ₂ correspond to the digit of the digital signal D ₂ and so on. When the device is used to convert electrical signals into sound waves, the spatial addition of acoustic signals from acoustic emitters 2 ₁ ... 2 _N occurs. The total power of acoustic emitters P (Fig. 8k) is determined by formulas (5) and (6).

 The indicated power addition corresponds to the conversion from a digital signal to an analog acoustic signal.

In the embodiment of the device for converting electrical signals into sound waves, shown in FIG. 2, said matching of digital signal levels of bits D ₁ . ..D _N with the excitation signals of acoustic emitters 2 ₁ ... 2 _{N is} carried out in the formers 3 ₁ ... 3 _N. As in the embodiment of FIG. 1, acoustic emitters 2 ₁ ... 2 _{N are} excited by signals from the outputs of the excitation signal generating unit corresponding to the bits from the lowest D ₁ to the highest D _{N of the} digital signal. In this case, conversion to acoustic signals occurs, followed by their spatial addition.

In the embodiment of the device for converting electrical signals into sound waves, shown in FIG. 3, the excitation signal generating unit 1, in addition to the formers 3 ₁ ... 3 _N , contains modulators 4 ₁ ... 4 _N and a generator 5. The generator 5 supplies a signal U _f (Fig. 9e) with a frequency f greater than the sampling frequency F digital signal, to the second input of modulators 4 ₁ ... 4 _N , the first input of which receives an excitation signal from the formers 3 ₁ ... 3 _N , in which, as in the previous version, the digital signal levels of the bits D ₁ are matched. ..D _{N by} excitation signals of acoustic emitters 2 ₁ ... 2 _N. In modulators 4 ₁ ... 4 _N , the generator clock signal is “modulated” with 5 signals from the drivers 3 ₁ ... 3 _N , in other words, the pulse signal is filled with higher frequency signals. Thus, the output of modulators 4 ₁ . . . 4 _N , a clock signal of the generator 5 is generated, "modulated" by the excitation signals of the acoustic emitters 2 ₁ ... 2 _N. In this embodiment, acoustic emitters 2 ₁ ... 2 _N when emitting an acoustic signal P ₁ ... P ₄ (Fig. 9g ... 9k) oscillate with the clock frequency of the generator 5. The spatial addition of acoustic signals is carried out similarly to that described above. The only difference is that the total signal P (Fig. 9l) is modulated. Since, according to formulas (2) - (4), the clock frequency of the modulated signal is higher than the maximum frequency of sound perceived by a person, when listening to the total signal, only the envelope will be perceived - the original analog sound signal. Thus, the human hearing aid will act as a filter and detector.

An embodiment of the device for converting electrical signals into sound waves, shown in FIG. 4 differs from the embodiment of FIG. 3 by the fact that in the block for generating excitation signals 1, the clock frequency supplied to the blocks 4 ₁ . ..4 _N , the sampling frequency F is an integer number of times. The sampling frequency F is extracted from the digital signal in the sampling frequency extraction unit 6, and its multiplication is performed in the multiplier generator 7. In contrast to the previous version, the pulse sequences of the excitation signals contain an integer number of clock frequency periods, as a result of which some phase and other distortions.

An embodiment of the device for converting electrical signals into sound waves, shown in FIG. 5 differs from the embodiment of FIG. 3 in that the block for generating excitation signals 1 contains logic elements AND 8 ₁ ... 8 _N , at the first input of which a signal is supplied from the source of the digital signal, and to the second input - the signal of the generator 5. At the output of the logic elements AND 8 ₁ . . . 8 _N , “bursts of pulses” are formed with the clock frequency of the generator 5 and the duration corresponding to the duration of the logical “1” of the corresponding discharge of the digital signal. Thus, an in-pulse filling of the sequence of rectangular pulses of the digital signal with the clock frequency of the generator 5 is carried out. The outputs of the logic elements AND 8 ₁ ... 8 _{N are} connected to the formers 3 ₁ . . .3 _N , in which the levels of the digital signal of bits D ₁ ... D _N are matched with the excitation signals of acoustic emitters 2 ₁ ... 2 _N.

 If the digital signal is not presented in the form of a parallel N-bit code, then at the input of the device for converting electrical signals into sound waves, it is necessary to provide a decoder - a device for converting from a coded signal to a parallel N-bit code, necessary for the operation of the device corresponding to the invention.

 Various combinations of connections of blocks and nodes in a block for generating excitation signals 1 from the various embodiments presented above are also possible. In this case, options for the execution of blocks and nodes combining several functions are possible. For example, generators 5 and 7 may have control inputs and an input for supplying an external clock frequency. Control inputs can be used to supply control signals to generators, set multiplication factors, to switch modes and input signals. In addition, in an embodiment of the invention in which exciting signals with different frequencies of in-pulse filling are supplied to acoustic emitters, waiting generators can be introduced in front of the shapers (as in the embodiment in FIG. 2) to generate signals with certain parameters only when an input signal is applied to it .

 The invention is based on the principle of spatial addition of sound waves emitted by acoustic emitters. Various options for the location of acoustic emitters are possible: on the same plane (flat model) and in different planes (spatial model). Flat models (Fig. 7) include a circle, a rectangle, a polygon, an ellipse, single and multiple spirals, etc. and their combination. Spatial models can include a hemisphere, cone, pyramid, polyhedron, ellipsoid, hyperboloid, etc., and their combination. A mixed arrangement of acoustic emitters is possible — all acoustic emitters are located on a plane, but with different spatial orientations.

 Acoustic emitters can use various principles of conversion of electrical signals and can be made in the form of mechanical, piezoelectric, magnetostrictive, plasma, ionic, electrodynamic, etc. Acoustic emitters are possible using various technologies for converting electrical signals.

 The invention provides high reliability of reproduction of an audio signal in the entire frequency range, ease of coordination with sources of a digital audio signal, with relative simplicity of design and cost-effectiveness of manufacture.

 In the best way, the invention can be used to create devices for converting electrical signals into sound waves with high-quality characteristics and optimally coordinated with digital sources of sound signal, such as loudspeakers and speakers.

Claims (11)

1. The method of converting electrical signals into sound waves, in which the converted electrical signal of the sound range is represented as a digital signal in a parallel N-bit code and generate excitation signals of acoustic emitters, characterized in that the excitation signals of acoustic emitters are formed from each of N bits obtained digital signal in the form of sequences of rectangular pulses synchronous with binary sequences of the corresponding bits of the digital signal using n sequences of rectangular pulses, using N acoustic emitters, N sequences of acoustic pulse signals are generated in which the acoustic signal pulse corresponds to the logical "1" of the digital signal, and the gap between the acoustic signal pulses corresponds to the logical "0" of the digital signal, while the acoustic signal pulse power for a duration equal to the period of the sampling frequency of the digital signal, each of the N acoustic emitters is determined in accordance with the formula
P _i = P ₁ • 2 ^i-1 ,
where P _i is the acoustic pulse power of the i-th acoustic emitter, i = 1 ... N, excited by a sequence of rectangular pulses corresponding to the i-th digit of the digital signal;
P ₁ is the acoustic pulse power of the first acoustic emitter excited by a sequence of rectangular pulses corresponding to the least significant digit of the digital signal.  2. The method according to claim 1, characterized in that the sequence of rectangular pulses is formed with intrapulse filling of the signal with a frequency higher than the sampling frequency of the digital signal. 3. The method according to claim 2, characterized in that the frequency of the signal intrapulse filling is determined by the formula
f = m • F,
where f is the frequency of the signal intrapulse filling sequences of rectangular pulses;
m is a natural number;
F is the sampling frequency of the digital signal. 4. The method according to claim 2, characterized in that the frequency of the signal intrapulse filling is determined by the formula
f _i = m _i • F,
where f _i is the frequency of the intra-pulse filling signal of the i-th sequence of rectangular pulses, i = 1 ... N;
m _i is a natural number;
F is the sampling frequency of the digital signal. 5. A device for converting electrical signals into sound waves, comprising N acoustic emitters having excitation signal supply inputs, characterized in that it comprises an excitation signal generating unit, the inputs of which are connected to the output of the digital signal source of the audio range in a parallel N-bit code, the number N acoustic emitters is equal to the number of bits of the digital signal, wherein each of the N acoustic emitters is configured to emit acoustic signals in which ls acoustic signal corresponds to logic "1" digital signal, and the interval between the pulses of acoustic signal - logical "0" digital signal, the output level of the acoustic signal for the duration equal to the period of the sampling frequency of the digital signal determined by the formula
P _i = P ₁ • 2 ^i-1 ,
where P _i is the acoustic pulse power of the i-th acoustic emitter, i = 1 ... N, excited by a sequence of rectangular pulses corresponding to the i-th digit of the digital signal;
P ₁ is the acoustic pulse power of the first acoustic emitter excited by a sequence of rectangular pulses corresponding to the least significant digit of the digital signal, while the inputs of the excitation signal of each of the emitters from the 1st to the Nth are connected respectively to the outputs of the excitation signal generating unit corresponding to the bits with the youngest to oldest mentioned digital audio signal.  6. The device according to claim 5, characterized in that the excitation signal generating unit comprises N formers, the inputs of which are connected respectively to the inputs from the 1st to the Nth excitation signal generating unit, and the outputs are connected to the outputs of the excitation signal generating unit low-order to high-order bits of the digital audio signal.  7. The device according to claim 5, characterized in that the excitation signal generating unit comprises N formers, N modulators and a generator, while the inputs of the formers are connected respectively to the inputs from the 1st to the Nth excitation signal generating unit, and the outputs are connected to the first inputs of modulators, the outputs of which are connected to the outputs of the excitation signal generating unit, corresponding to the bits from the lowest to oldest of the digital signal of the sound range, the generator output is connected to the second inputs of the modulators.  8. The device according to claim 5, characterized in that the excitation signal generation unit comprises N shapers, N modulators, a sampling frequency allocation block for the input digital signal and a multiplier generator, while the shapers inputs are connected respectively to the inputs from the 1st to the N- of the first block of generating excitation signals, and the outputs are with the first inputs of modulators, the outputs of which are connected to the outputs of the block of generating excitation signals corresponding to the bits from the lowest to oldest of the digital sound signal azone, inputs the block allocation rate of the input digital signal sample are connected to inputs to the 1st to N-th blocks forming the excitation signal, the output sampling frequency block allocation input digital signal is coupled to the input of the generator-multiplier whose output is connected to second inputs of modulators.  9. The device according to claim 5, characterized in that the excitation signal generating unit comprises N formers, N logical elements AND and a generator, while the first inputs of the logical elements AND are connected respectively to the inputs from the 1st to the Nth excitation signal generating unit , inputs of logical elements AND are connected respectively to the inputs of the formers, the outputs of which are connected to the outputs of the unit for generating excitation signals corresponding to the bits from the lowest to oldest of the mentioned digital signal of the audio range, the output q generator connected to the second inputs of the logical elements I. 10. The device according to any one of paragraphs.5 to 9, characterized in that at least one acoustic emitter is made in the form of a group of acoustic emitters of lower power with a total power of said group of emitters equal to the power P _{i of} said at least one acoustic emitter. 11. The device according to claim 10, characterized in that the said group of acoustic emitters with a total power of P _i consists of 2 ^i-1 identical elementary emitters with a power of P ₁ .

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