KR20010033068A - Apparatus and methods for enhancing electronic audio signals - Google Patents

Abstract

The present invention relates to a method and apparatus for augmenting an electronic audio signal in a simple and low cost manner in such a way that the sound quality of the audible sound generated from the audio signal approaches closer to that of the original sound vividly heard in an acoustically designed environment. The present invention restores the perception of harmonics that are typically missing in electronic audio signals. The apparatus comprises a passive circuit 5 which causes the input audio signal (s) to be distorted such that an augmented audio signal representing an improved harmonic quality of the original input audio signal (s) is produced. This passive circuit includes at least one transformer (s).

Description

Apparatus and methods for enhancing electronic audio signals

Typically, listening to music, song sounds, or other such complex sounds vividly is thought to be more pleasant than listening to the same sound after it has been converted to an electronic audio signal, reconverted back to an audible sound.

Many of the sounds we hear, especially musical tunes, are often complicated. For example, a musical melody with a fundamental path or fundamental frequency includes components of the fundamental frequency, commonly called harmonics. These harmonics often produce the sound quality or timbre of a sound, such as musical melody unique to an instrument or other sound producing source. In other words, these harmonics enrich the sound we hear. Many sound reproduction systems have been developed that attempt to add harmonic enhancement to audio signals. However, these systems are often very complex and expensive, and the sound quality produced by such systems lacks the perceived sound quality of the original sound that still sounds vivid.

When converted to an audible sound, it is detected as showing a better harmonic quality than that of the original input audio signal, generating an enhanced electronic audio signal, and more closely replicating the experience of listening to the original live sound in an acoustically designed environment. Relatively uncomplicated and inexpensive systems for generating augmented electronic audio signals have been developed. Such a system is disclosed in US Pat. No. 5,361,306, assigned to the assignee of the present application. A typical circuit disclosed in this patent 5,361,306 includes an input stage having a field induction coil and an output stage comprising an electromagnetic field receptor (eg, another coil) and an output stage. Input audio signals are sent through an induction coil to set up the electromagnetic field. The field induction coil and the electromagnetic field receptor are weakly coupled so that the enhanced audio signal is available at the output stage when the input audio signal is transmitted through the field induction coil.

The present invention is an improvement on the invention disclosed in US Pat. No. 5,361,306. The present invention is less complicated in structure and less expensive.

The present invention relates to augmentation of electronic audio signals for improving sound quality generated from electronic audio signals, and more particularly, to an apparatus and method for harmonic augmentation of an electronic audio signal without the use of active circuitry.

1 is a perspective view of a transformer constructed in accordance with a first embodiment of the present invention;

FIG. 2 is a perspective view of a bobbin of the transformer illustrated in FIG. 1. FIG.

3 is taken along the straight line 3-3 of FIG.

4 is a schematic side view of the bobbin illustrated in FIG. 3;

5 is a circuit diagram of a passive circuit constructed in accordance with a first embodiment of the present invention coupled to an audio signal source and an audio amplifier.

6 is an exploded view of two E-core sections and two I-core sections of the core illustrated in FIG.

7 is an illustration of first, second and third frequency response curves generated by a passive circuit constructed in accordance with a first embodiment of the present invention.

7A is an illustration of a frequency response curve generated by a passive circuit adapted for use in a CB radio.

8 is a circuit diagram of a passive circuit constructed in accordance with a second embodiment of the present invention coupled to an audio source and an audio amplifier.

9 is a perspective view of a first transformer constructed in accordance with a second embodiment of the present invention.

10 is a perspective view of the bobbin of the transformer illustrated in FIG. 9.

10A is a schematic side view of the bobbin illustrated in FIG. 10.

11 is a view taken along the straight line 11-11 of FIG.

12 is a perspective view of a second transformer constructed in accordance with a second embodiment of the present invention.

13 is a perspective view of the bobbin of the transformer illustrated in FIG. 12.

13A is a schematic side view of the bobbin illustrated in FIG. 13.

14 is a view taken along the straight line 14-14 of FIG.

Figure 15 is an illustration of first, second and third frequency response curves generated by a passive circuit constructed in accordance with a second embodiment of the present invention.

In accordance with the present invention, numerous methods and apparatus for augmenting the electronic audio signal simply and inexpensively in such a way that the sound quality of the audible sound generated from the audio signal more closely approaches the sound quality of the original sound vivid in an acoustically designed environment are provided. Is provided. Sound generated from an augmented audio signal in accordance with the present invention appears to resist degradation at high volume and tends to eliminate or at least significantly reduce sweet spots. The circuit according to the invention is preferably interlocked towards restoring the perception of harmonics which are normally lost due to audio conversion equipment, limitations of the recording process, defects in the recording medium, and the like.

In one aspect of the invention, an apparatus for enhancing the sound quality of an input audio signal composed of frequency components in a frequency band having a lower limit and an upper limit is provided. The apparatus according to the principles of the invention comprises passive circuitry such that such an input audio signal transmitted therethrough is distorted into an enhanced audio signal exhibiting an improved harmonic quality compared to the sound quality of the original input audio signal. This distortion is nonlinear amplification of the frequency component of the input audio signal. Amplification is changed in such a way that the human ear can better perceive or improve and record the harmonic characteristics of the audio signal.

In the first embodiment of the present invention, the amplification of the frequency component in the input audio signal increases as the frequency components increase from the intermediate frequency to the peak high frequency. The intermediate frequency may be referred to as the reference frequency. Above the peak high frequency, it may be desirable for the amplification to decrease as the frequency component increases at frequencies from the peak high frequency to the upper limit frequency. Instead of a single high frequency peak high frequency, it may be desirable that the peak high frequency is a frequency range such that the frequency components that fall within that range generally have the same amplitude. The peak high frequency may range from about 6 KHz to about 30 KHz. The amplification of the frequency component (s) at the peak high frequency may be about 1.5 to about 3.0 times the amplification of the intermediate frequency component.

In a second embodiment of the invention, the amplification of the frequency component in the input audio signal is increased as the frequency component increases at a frequency from the first intermediate frequency to the peak high frequency and decreases at a frequency from the second intermediate frequency to the peak low frequency. Increases. The first and second intermediate frequencies may be referred to as first and second reference frequencies. The first and second intermediate frequencies may be the same frequency or different frequencies. Above the peak high frequency, it may be desirable for the amplification to decrease as the frequency component increases at the peak frequency at the peak high frequency. Below the peak low frequency, it may be desirable for the amplification to decrease as the frequency component decreases at frequencies from the peak low frequency to the lower limit frequency.

Instead of each being a single frequency, it may be desirable that the peak high frequency, peak low frequency, or both, be a frequency range such that the frequency components belonging to each range generally have the same amplitude. The peak high frequency may range from about 6KHz to about 30KHz. The amplification of the frequency component (s) at the peak high frequency may be about 1.5 to about 3.0 times the amplification of the first intermediate frequency component. The peak low frequency may range from about 20 Hz to about 1 KHz. The amplification of the frequency component (s) at the peak low frequency may be about 1.25 times to about 2.0 times the amplification of the second intermediate frequency component.

According to a first embodiment of the invention, the passive circuit nonlinearly modulates the frequency components of the input audio signal so that the amplification of the frequency components of the input audio signal is increased as the frequencies increase from intermediate to peak high frequencies. It may include a single transformer to amplify. Distortion caused by a single transformer can be described in the following equivalent manner. A single transformer amplifies the frequency components of the input audio signal such that the frequency components of the input audio signal increase in amplitude as the frequency components increase at frequencies from intermediate to peak high frequencies.

According to a second embodiment of the invention, the passive circuit comprises a frequency of the input audio signal as the frequency components increase at frequencies from the first intermediate frequency to the peak high frequency and decrease at frequencies from the second intermediate frequency to the peak low frequency. First and second transformers for non-linearly amplifying the frequency components of the input audio signal such that amplification of the components is increased. The distortion caused by the first and second transformers can also be described in the following equivalent manner. The first and second transformers increase the frequency components of the input audio signal in amplitude as the frequency components decrease at frequencies from the first intermediate frequency to the peak high frequency and decrease at frequencies from the second intermediate frequency to the peak low frequency. To amplify the frequency components of the input audio signal.

According to a second embodiment of the invention, there is provided an audio system comprising an audio source, an audio amplifier and a passive circuit. The audio source generates an input audio signal consisting of frequency components in the frequency band having an upper limit and a lower limit. The audio amplifier generates a speaker drive signal. The passive circuit couples the input audio signal to the audio amplifier and distorts the input audio signal into an augmented audio signal that exhibits an improved harmonic quality compared to that of the input audio signal when transmitted through it.

It is desirable that no active elements be coupled between the audio source and the audio amplifier.

The passive circuit may include a single transformer that affects the amplitude distortion of the input signal as limited by the first portion of the frequency response curve. The first portion of the curve increases nonlinearly from the intermediate frequency to the peak high frequency. Alternatively, the passive circuit may include first and second transformers that affect the amplification distortion of the input signal as defined by the first and second portions of the frequency response curve. The first portion of the curve increases nonlinearly from the first intermediate frequency to the peak high frequency. The second curved portion increases nonlinearly from the second intermediate frequency to the peak low frequency. The first and second intermediate frequencies may be the same frequency or different frequencies.

According to a third aspect of the invention, a method of enhancing the sound quality of electronic audio signals is provided. The method enhances an input audio signal by providing an input audio signal consisting of frequency components in a frequency band having an upper limit and a lower limit, and passing the input audio signal through a passive circuit to amplify the frequency components of the input signal. Distortion to the audio signal. According to one embodiment of the invention, the amplification of the frequency components of the input audio signal increases as the frequency components increase at frequencies from intermediate to peak high frequencies. According to another embodiment of the invention, amplification of the frequency components of the input audio signal as the frequency components increase at frequencies from the first intermediate frequency to the peak high frequency and decrease at frequencies from the second intermediate frequency to the peak low frequency This increases. The first and second intermediate frequencies may be the same frequency or different frequencies.

The method may comprise processing one or more enhanced audio signals into sound. It is intended that the scope of the invention include the sound so produced. Current augmented audio signals and sounds produced therefrom include audio signals and sounds with frequency components that fall within the range of normal human hearing (ie, approximately 20 Hz to 20 KHz).

The method of the invention may comprise transmitting one or more audio signals augmented in accordance with the invention from one location to another. The method may further comprise recording one or more current enhanced audio signals onto a recording medium. The scope of the invention is also intended to include a recording medium having one or more current enhanced audio signals recorded thereon. The recording medium may be a magnetic recording medium (eg, reel-to-reel tape, cassette tape, magnetic disc, etc.) or an optical recording medium (eg, compact disc, video disc, etc.). The invention is not intended to be limited to any particular type of recording medium or method of recording thereon.

The present invention provides an apparatus and method for enhancing the harmonic quality of an electronic audio signal, in particular an audio signal having a complex waveform (i.e. music, song, speech, animal sound, natural sound, equipment noise, etc.). To provide. Audio signals enhanced according to the invention exhibit an improved harmonic quality compared to that of the input electronic audio signal. Similar harmonic enhancements are described in US Pat. No. 5,361,306; US patent application Ser. No. 08 / 472,876, filed Jun. 7, 1995 under the heading Electronic Audio Signal Enhancer and Method thereof; And Harmonic Enhancement Apparatus and Method of Electronic Audio Signals, which may be obtained using the circuit disclosed in U.S. Patent Application No. 08 / 909,807, filed August 12,1997, which is incorporated herein by reference. It describes as.

The lessons and disclosures of the present invention indicate that there are a variety of different ways of obtaining the same or similar harmonic enhancement in the electronic audio signal. In providing the lessons and typical circuits disclosed herein, it would be a matter of simple attempts and error experiments, if necessary, to those skilled in the art to design additional ways to achieve the same or similar augmentation effects. Accordingly, the general purpose and specialty circuits disclosed herein are by way of example only, and the invention is not intended to be so limited.

While the invention has been described in terms of specific embodiments, it will be apparent to those skilled in the art that various modifications, rearrangements, and substitutions can be made without departing from the spirit of the invention. Accordingly, the scope of the present invention is limited only by the claims appended hereto.

Each of the special exemplary embodiments described in this application produces an augmentation of electronic audio signals. The apparatus according to the principles of the present invention comprises a passive circuit capable of distorting the input audio signal transmitted through it by amplifying nonlinearly (ie, non-uniformly) the augmenting harmonics or frequency components in the input audio signal. By increasing the amplitude of the augmenting harmonics in this way, the resulting augmented audio signal exhibits an improved harmonic quality compared to that of the input audio signal.

This circuit is effectively employed to perform augmentation without using any active elements such as amplifiers, transistors, tubes, etc. in use. Thus, passive circuitry does not power the input audio signal.

Example 1

A passive circuit 5 for augmenting an electronic audio signal constructed in accordance with the first embodiment of the invention is illustrated in the circuit diagram of FIG. 5. This circuit 5 comprises a single transformer 10. Transformer 10 includes a bobbin 20, a ferromagnetic core 30, and two magnetically coupled coils 40 and 42. See FIGS. 1-3 and 5.

Bobbin 20 may be formed from polymeric material reinforcing fibers. In the illustrated embodiment, the bobbin 20 comprises nylon glass reinforced fibers. The bobbin 20 has a substantially rectangular tubular portion 22 having a core receiving opening 22a extending therethrough. Opposite ends of this tubular part 22 are provided with first and second flanges 24 and 25. The wall thickness of each tubular portion 22 and flanges 24 and 26 is about 0.40 inches. The width W _F and length L _F of each flange 24 and 26 are about 1.48 inches and 1.54 inches, respectively. The width W _F , height H _A , and length L _F of the opening 22a are about 0.765 inches, 1.02 inches, and 0.765 inches, respectively. Each flange 24 and 26 includes six L-shaped pin-containing portions 24a and 26a embedded therein. Twelve pins are designated in FIGS. P ₁ -P ₁₂ . One such bobbin is commercially available from Plastron Corporation under the trade name "94HB". The first coil 40 is limited by the first and second primary windings 40a and 40b connected in series. The second coil 42 is limited by the first and second secondary windings 42a and 42b connected in series.

When 39 is a wire gauge, the first wire 44 of the type “39 single-poly-nylon (SPN) 155 ° C.” wire is an outer coating material and 155 ° C. is used to form the first winding 40a. The wire temperature rating is randomly wound clockwise relative to the tubular portion 22. The winding 40a includes 1000 revolutions and has a DC resistance of about 285 Ω ± 10%. It is soldered or otherwise connected to pins P ₁ and P ₂ . See FIGS. 2, 4 and 5. The first layer 51 of the polymer reinforced fiber film is wound around the first primary winding 40a. See FIG. 3. In the illustrated embodiment, the film comprises a polyester reinforced glass fiber film having a thickness of about 0.0065 inches. Such films are commercially available from TESA Inc. under the trade name "IL-4426". The first layer 51 has a thickness of about 0.0065 inches.

A second wire 48 of the type “34SPN155 ° C.” wire is wound randomly around the first film layer 51 counterclockwise to form a second secondary winding 42a. The winding portion 42a includes 2000 rotations and has a DC resistance of about 156 Ω ± 10%. It is soldered or otherwise connected to pins P ₇ and P ₈ . The second layer 53 of the polymer reinforced fiber film is wound around the first secondary winding 42a. The second layer 53 has a thickness of about 0.13 inches.

A third wire 50 of the type “39SPN155 ° C.” wire is randomly wound clockwise around the second film layer 53 to form a second primary winding 40a. The winding 40b includes 1000 revolutions and has a DC resistance of about 335 Ω ± 10%. It is soldered or otherwise connected to pins P ₃ and P ₆ . The third layer 55 of the polymer reinforced fiber film is wound around the second primary winding 40b. The third layer 55 has a thickness of about 0.13 inches. The first and second primary windings 40a and 40b are connected in series via pin P ₃ to limit the first coil 40 extending between pins P ₁ and P ₆ .

A fourth wire 48 of the type “34SPN155 ° C.” wire is wound randomly around the third film layer 55 counterclockwise to form the second secondary winding 42b. The winding portion 42b includes 2000 rotations and has a DC resistance of about 186 Ω ± 10%. It is soldered or otherwise connected to pins P ₈ and P ₁₁ . The fourth layer 57 of the polymer reinforced fiber film is wound around the second secondary winding 42b. The fourth layer 57 has a thickness of about 0.0065 inches. The first and second secondary windings 42a and 42b are connected in series via pin P ₉ to limit the second coil 42 extending between pins P ₇ and P ₁₁ .

The first, second, third and fourth wires 44, 48, 50 and 52 are available from Phelps Dodge Corporation.

Coil 30 is formed from numerous E-core and I-core sections 32 and 34. See FIGS. 1, 3 and 6. These sections 32 and 34 include ferromagnetic materials such as 24 gauge, M50 grade steel. Sections 32 and 34 are assembled by alternately stacking E-core and I-core sections 32 and 34 such that each I-core section 34 lies between adjacent E-core sections 32. . See FIG. 6. A single I-core section 34 may be laminated to each E-core section 32 before being assembled. The central portion 32a of the E-core section 32 fills the core receiving opening 22a of the bobbin 20. After assembly, the sections 32 and 34 are laminated to each other by varnishing the outer surfaces of the assembled sections 32 and 34. Such varnish is available under the name P.D. It is available from George Co., Ltd. In the illustrated embodiment, each E-core section 32 is about 0.025 inches thick. Each I-core section 34 has a thickness of about 0.025 inches. The length Lc of the core 30 is about 2.25 inches and the thickness Tc of the core 30 is about 0.750 inches. The height Hc of the core 30 is about 1.875 inches. See FIG. 1.

The primary windings 40a and 40b not only achieve a high degree of engagement between the primary windings 40a and 40b and the secondary windings 42a and 42b but also the windings 40a, 40b and 42a and 42b. It is interleaved with the secondary windings 42a and 42b to minimize the capacitance of the liver. Transformer 10 has a very low magnetic flux density to increase transformer 10's ability to receive lower level audio signals, increase primary inductive resistance, reduce capacitive reactance, and increase the overall frequency response of the circuit. Is designed as.

The passive circuit 5 may comprise an audio signal source S, for example a CD player, a laser disc player, a tape player, a radio, a digital audio tape (DAT) player and an audio amplifier A, for example a preamplification step, for example a solid state or It is intended to be directly coupled to a tube preamplifier or power amplification stage, such as an integrated power amplifier, a tube power amplifier, a solid state power amplifier or a hybrid power amplifier. Any commercially available connector (s) can be used to connect the passive circuit 5 to a signal source comprising a single-ended connector or a balanced connector. No active element is connected between source S and audio amplifier A. See FIG. 5. When the transformer is coupled in this way and an input audio signal consisting of frequency components in the frequency band with lower and upper limits is transmitted through transformer 10, the audio signal exhibits an improved harmonic quality compared to that of the original input audio signal. It is distorted by the augmented audio signal. This distortion is nonlinear amplification of at least some of the frequency components of the input audio signal. The amplification is preferably changed in such a way that the human ear perceives or improves and records the harmonic characteristics of the audio signal. For example, frequency components near the upper limit of the frequency band may be amplified by an amount exceeding an amount in which intermediate frequency components between the lower and upper limits of the frequency band are amplified.

In FIG. 7, first, second and third typical frequency response curves C ₁ , C ₂ , C ₃ generated by the passive circuit 5 constructed in accordance with the illustrated embodiment are shown. For each curve, the output voltage is plotted against the frequency for the normalized input audio signals. The frequency response curves C ₁ , C ₂ , C ₃ are signal sources which are conventional signal generators which generate a 1 V input signal swept the first coil 40 of the transformer 10 through a frequency band of about 20 Hz to about 22 KHz. 20 kV (curve C ₁ ), which is connected to S and whose load represents the equivalent impedance as seen by transformer 10 when the second coil 42 of transformer 10 is connected to a conventional audio amplifier input, It was obtained by connecting to a resistance rod of 25 kV (curve C ₂ ) and 100 kV (curve C ₃ ). No active device intervened between the input source S and any resistive load.

Each of the first, second and second curves C ₁ , C ₂ , C ₃ has an input audio signal passing through the passive circuit 5 and the output end of the passive circuit 5 (ie the second coil 42). It represents the amplification that occurs for the frequency components of the input audio signal when connected to this resistive load. The resistive rod is 20 kW for curve C ₁ , 50 kW for curve C ₂ , and 100 kW for curve C ₃ . For these three curves C ₁ , C ₂ , C ₃ , the input audio signal consisting of frequency components belonging to the frequency band with a lower limit and an upper limit appears to be distorted when transmitted through the passive circuit 5. This distortion is nonlinear amplification of the frequency components of the input audio signal. More specifically, the amplification of the frequency components of the input audio signal is substantially constant for intermediate frequency components belonging to the frequency band of about 20 Hz to about 3.5 KHz, at frequencies ranging from about 3.5 KHz to peak high frequencies of about 20 KHz. Increase for increasing frequency components. Above about 20 KHz, the amplification decreases as the frequency components increase at frequencies from the peak high frequency of about 20 KHz to the upper limit frequency of about 22 KHz. The amplification or gain for intermediate frequency components belonging to the frequency band of about 20 Hz to about 5 KHz is about 1.5 to 2.0 and about 2.6 to about 4.8 for frequency components at peak high frequencies. Thus, for curve C ₁ , the amplification of the frequency component at peak high frequency is about 1.5 times the average amplification of the range of intermediate frequency components from 20 Hz to 3.5 KHz. For curve C ₂ , the amplification of the frequency component at peak high frequency is about 2.0 times the average amplification of the range of intermediate frequency components from 20 Hz to 3.5 KHz. For curve C ₃ , the amplification of the frequency component at the peak high frequency is about 2.3 times the average amplification of the range of intermediate frequency components from 20 Hz to 3.5 KHz.

The frequency response of the passive circuit 5 for a given load may be as follows: the number of revolutions of one or both of the coils 40 and 42; The size and type of wire used to construct the coils 40 and 42; DC resistance of at least one of the first and second primary windings 40a and 40b and the first and second windings 42a and 42b; The size of the core 30; And gauges and grades of materials used to form the core 30 are believed to be varied. It is also believed that when the capacitance of the transformer 10 is changed, the amplification of the frequency components at the upper limit of the frequency band can be changed. Capacitance is the thickness of one or more film layers 51, 53, and 55; DC resistance of one or more windings 40a, 40b, 42a and 42b; And / or by changing the position of one or more windings 40a, 40b, 42a and 42b. Thus, when a transformer is coupled to a given load, an empirical decision is needed to accurately determine the configuration of the transformer 10 to affect the desired frequency response.

Thus, according to the first embodiment of the present invention, the input signal is distorted into an augmented audio signal by passing the input audio signal through the passive circuit 5 to amplify the frequency components of the input signal. The amplification of the frequency components in the input audio signal increases as the frequency components increase at frequencies from intermediate to peak high frequencies. Above the peak high frequency, it is desirable that the amplification decrease as the frequency components increase at frequencies from the peak high frequency to the upper limit frequency.

With respect to the first embodiment of the present invention, instead of the peak high frequency including a single frequency, it is preferable that the peak high frequency be a relatively narrow range of frequencies so that the frequency components belonging to the narrow range generally have the same amplitude. It is expected.

Curves C ₁ , C ₂ and C ₃ are provided for illustrative purposes only. It is believed that amplification of intermediate frequency components, for example frequency components from about 20 Hz to about 3.5 KHz, may have a single gain (1.0) below 1.0 or above 1.0. The peak high frequency may range from about 6KHz to about 30KHz. The amplification of the frequency component (s) at the peak high frequency may be about 1.5 to about 3.0 times the amplification of the intermediate frequency component among the average amplifications in the range of the intermediate frequency components.

The order of the windings 40a, 40b, 42a and 42b is expected to be varied to shield incoming electromagnetic interference (EMI) and radio frequency interference (RFI) radiation. Thus, the second wire 48 is first wound on the tubular portion 22 in a counterclockwise direction, then the first wire 44 wire is wound in a clockwise direction, and then the fourth wire 52 is counterclockwise. , The third wire 50 is then wound in a clockwise direction. Thus, the order of the windings is as follows: the first secondary winding 42a follows the first primary winding 40a, the second secondary winding 42b, and the next. The second primary winding part 40b follows. The second primary winding 40b acts as a shield whose own flux line negates most incoming EMI and RFI radiation.

It is also envisaged that passive circuits comprising single or double transformers can be built for use in CB radios. The single or double transformer is coupled to the output of a conventional detector circuit in a CB radio via a low pass filter comprising a capacitor in series with a resistor at its input and to an audio attenuator in the CB radio at its output.

In FIG. 7A, a typical frequency response curve generated by a single transformer passive circuit constructed in accordance with the present invention is shown. In this curve, the output voltage is plotted against the frequency for the normalized input audio signal. The frequency response curve is a conventional signal generator that generates a 1V input signal swept through a frequency band of about 20 Hz to about 20 KHz through a low pass filter comprising a capacitor (22 microfarad) in series with a resistor (250 Ω). Was obtained by connecting the second coil of the transformer to a resistance rod of about 43 kΩ which represents the equivalent impedance the transformer can see when its load is connected to the signal source S and its load is connected to the input of a conventional audio amplifier of a CB radio. . No active device intervened between the input source and the resistive load.

The curve of FIG. 7A shows the amplification that occurs for the frequency component of the input audio signal when the input audio signal passes through the passive circuit and the output end of the passive circuit (ie, the second coil) is connected to the resistive load. As noted above, the resistive rod is about 43 kV for the curve illustrated in FIG. 7A. From this curve, it is apparent that the input audio signal constituting the frequency components belonging to the lower and upper frequency bands is distorted when transmitted through the passive circuit. This distortion is non-uniform amplification of the frequency components of the input audio signal. More specifically, the amplification of the frequency components of the input audio signal gradually increases for intermediate frequency components belonging to the frequency band of about 100 Hz to about 300 Hz and increases at frequencies ranging from about 300 Hz to peak high frequencies of about 300 Hz. It increases at an increased rate relative to the components. Above the peak high frequency of about 10 KHz, the amplification decreases as the frequency components increase at a frequency from the peak high frequency of about 10 KHz to the upper limit frequency of about 20 KHz. The amplification or gain in the curve of FIG. 7A ranges from about 1.6 to about 1.8 for intermediate frequency components belonging to the frequency band of about 100 Hz to about 300 Hz, and is about 3.8 for frequency components at or near the peak high frequency. .

The curve illustrated in FIG. 7A is provided for illustrative purposes only. It is believed that amplification of intermediate frequency components, eg, frequency components from about 100 Hz to about 300 Hz, may have a single gain (1.0) below 1.0 or above 1.0. Peak high frequencies can range from about 6KHz to about 15KHz for a single transformer circuit to be used in a CB radio.

When inserted into a CB radio, a single transformer will typically receive an input audio signal consisting only of frequency components in the range of about 300 Hz to about 3 KHz.

Example 2

A passive circuit 300 comprising first and second transformers 100 and 200 constructed in accordance with a second embodiment of the invention is illustrated in the circuit diagram of FIG. 8. The first and second transformers 100 and 200 are inevitably built in the same manner as the transformer 10 and are illustrated in FIGS. 9, 10, 10a and 11 and 12, 13, 13a and 14. The first transformer 100 includes a bobbin 120 (see FIGS. 10 and 10A), a ferromagnetic core 130 (see FIG. 9) and two magnetically coupled coils 140 and 142 (see FIG. 8). . The second transformer 200 includes a bobbin 220 (see FIGS. 13 and 13A), a ferromagnetic core 230 (see FIG. 12) and two magnetically coupled coils 240 and 242 (see FIG. 8). .

Bobbins 120 and 220 are necessarily constructed in the same manner as the bobbin 20. In the illustrated embodiment, the bobbins 120 and 220 are formed from nylon glass reinforced fibers.

The bobbin 120 has a substantially rectangular shaped tubular portion 122 having a core receiving opening 122a extending therethrough. Opposite ends of this tubular portion 122 are provided with first and second flanges 124 and 126. The wall thickness of each tubular portion 122 and flanges 124 and 126 is about 0.40 inches. The width W _F and length L _F of each flange 124 and 126 are about 1.23 inches and 1.34 inches, respectively. The width W _A , height H _A and length L _A of the opening 122a are about 0.640 inches, 0.830 inches and 0.640 inches, respectively. Each flange 124 and 126 includes six L-shaped pin-containing portions 124a and 126a embedded therein. Twelve pins are designated P ₁ -P ₁₂ in the figure.

The bobbin 220 has a substantially rectangular shaped tubular portion 222 with a core receiving opening 222a extending therethrough. Opposite ends of this tubular portion 222 are provided with first and second flanges 224 and 226. The wall thickness of each tubular portion 222 and flanges 224 and 226 is about 0.40 inches. The width W _F and length L _F of each flange 224 and 226 are about 1.48 inches and 1.54 inches, respectively. The width W _A , height H _A and length L _A of the opening 222a are about 0.765 inches, 1.02 inches and 0.765 inches, respectively. Each flange 224 and 226 includes six L-shaped pin-containing portions 224a and 226a embedded therein. Twelve pins are designated P ₁ -P ₁₂ in the figure.

The first coil 140 of the transformer 100 is limited by the first and second primary windings 140a and 140b connected in series. The second coil 142 is limited by the first and second secondary windings 142a and 142b connected in series.

A first wire 144 of the type “39 single-poly-nylon (SPN) 155 ° C.” wire is wound randomly clockwise around the tubular portion 122 to form the first primary winding 140a. Lose. The winding 140a includes 500 rotations and has a DC resistance of about 106 Ω ± 10%. It is soldered or otherwise connected to pins P ₁ and P ₃ . See FIGS. 8, 10 and 10a. The first layer 151 of the polymer reinforced fiber film, such as discussed above with respect to the first embodiment of the present invention, is wound around the first primary winding 140a. See FIG. 11. The first layer 151 has a thickness of about 0.0065 inches.

A second wire 148 of the type “32PN155 ° C.” wire is randomly wound in a counterclockwise direction around the first film layer 151 to form the first secondary winding 142a. The winding 142a includes 1000 revolutions and has a DC resistance of about 46Ω ± 10%. It is soldered or otherwise connected to pins P ₇ and P ₈ . The second layer 153 of the polymer reinforced fiber film is wound around the first secondary winding 142a. See FIG. 1. The second layer 153 has a thickness of about 0.0065 inches.

A third wire 150 of the type “39SPN155 ° C.” wire is randomly wound clockwise around the second film layer 153 to form a second primary winding 140a. Wire 150 is soldered or otherwise connected to pin P ₃ , randomly wound about 400 times around second film layer 153, and connected to pin P ₅ . In the illustrated embodiment, after being connected to pin P ₅ , the third wire 150 is randomly wound around the second film layer 153 again 100 times, soldered or otherwise connected to pin P ₆ . In this embodiment, the winding 140b extending between pins P ₃ and P ₅ includes 400 rotations and has a DC resistance of about 107 Ω ± 10%. The third layer 155 of the polymer reinforced fiber film is wound around the second primary winding 140b. The third layer 155 has a thickness of about 0.0065 inches. The first and second primary windings 140a and 140b are connected in series via pin P ₃ to limit the first coil 140 extending between pins P ₁ and P ₆ .

A fourth wire 152 of the type “34SPN155 ° C.” wire is wound randomly around the third film layer 155 in a counterclockwise direction to form the second secondary winding 142b. The winding 142b includes 1000 revolutions and has a DC resistance of about 58.0Ω ± 10%. It is soldered or otherwise connected to pins P ₈ and P ₁₁ . The fourth layer 157 of the polymer reinforced fiber film is wound around the second secondary winding 142b. The fourth layer 157 has a thickness of about 0.0065 inches. The first and second secondary windings 142a and 142b of the first transformer 100 are connected in series via pin P ₉ to limit the second coil 142 extending between pins P ₇ and P ₁₁ .

Wires 144, 148, 150, and 152 are available from Phelps Dodge Corporation.

The core 130 of the first transformer is formed from numerous E-core and I-core sections 132 and 134 in substantially the same manner as described above with respect to the core 30. See FIGS. 9 and 11. These sections 132 and 134 include ferromagnetic materials such as 29 gauge, M6 grade steel. In the illustrated embodiment, each E-core section 132 is about 0.14 inches thick. Each I-core section 134 has a thickness of about 0.14 inches. The length Lc of the core 130 is about 1.875 inches, the thickness Tc of the core 130 is about 0.625 inches, and the height Hc of the core 130 is about 1.5625 inches. See FIG. 9.

The primary windings 140a and 140b not only achieve a high degree of engagement between the primary windings 140a and 140b and the secondary windings 142a and 142b, but also the windings 140a, 140b and 142a and 142b. Interleaved with secondary windings 142a and 142b to minimize capacitance of the liver. Transformer 100 is highly capable of increasing the circuit 300's ability to accept lower level audio signals, increasing primary inductive resistance, reducing capacitive reactance, and increasing the overall frequency response of the circuit 300. It is designed with low magnetic flux density.

The first coil 240 of the second transformer 200 is limited by the first and second primary windings 240a and 240b connected in series. See FIG. 8. The second coil 242 is limited by the first and second secondary windings 242a and 242b connected in series.

A first wire 244 of the type “39 single-poly-nylon (SPN) 155 ° C.” wire is clocked around the tubular portion 222 of the bobbin 220 to form a first primary winding 240a. In a random direction. The winding portion 240a includes 1000 revolutions and has a DC resistance of about 250 Ω ± 10%. It is soldered or otherwise connected to pins P ₁ and P ₃ . See FIGS. 8, 13 and 13a. The first layer 251 of the polymer reinforced fiber film, such as that used in the first embodiment, is wound around the first primary winding 240a. First layer 251 has a thickness of about 0.0065 inches.

A second wire 248 of the type “34PN155 ° C.” wire is wound randomly around the first film layer 251 in a counterclockwise direction to form the first secondary winding 242a. The winding 242a includes 2000 revolutions and has a DC resistance of about 156 Ω ± 10%. It is soldered or otherwise connected to pins P ₇ and P ₈ . The second layer 253 of the polymer reinforced fiber film is wound around the first secondary winding 242a. See FIG. 14. The second layer has a thickness of about 0.0065 inches.

A third wire 250 of the type “39SPN155 ° C.” wire is randomly wound clockwise around the second film layer 253 to form a second primary winding 240a. Wire 250 is soldered or otherwise connected to pin P ₃ , randomly wound about 500 times around second film layer 253, and connected to pin P ₆ . In the illustrated embodiment, after being connected to pin P ₅ , the third wire 250 is randomly wound around the second film layer 253 and 500 times, soldered or otherwise connected to pin P ₆ . In this embodiment, the winding 240b extending between pins P ₃ and P ₅ includes 500 revolutions and has a DC resistance of about 150Ω ± 10%. The third layer 255 of the polymer reinforced fiber film is wound around the second primary winding 240b. The third layer 225 has a thickness of about 0.0065 inches. The first and second primary windings 240a and 240b of the second transformer 200 are connected in series via pin P ₃ to limit the first coil 240 extending between pins P ₁ and P ₅ .

A fourth wire 252 of the type “34SPN155 ° C.” wire is randomly wound in the counterclockwise direction around the third film layer 255 to form the second secondary winding 242b. The winding 242b includes 2000 revolutions and has a DC resistance of about 186 Ω ± 10%. It is soldered or otherwise connected to pins P ₈ and P ₁₁ . The fourth layer 257 of the polymer reinforced fiber film (not shown) is wound around the second secondary winding 242b. The fourth layer 257 has a thickness of about 0.0065 inches. The first and second secondary windings 242a and 242b of the second transformer 200 are connected in series via pin P ₉ to limit the second coil 242 extending between pins P ₇ and P ₁₁ .

Wires 244, 248, 250, and 252 are available from Phelps Dodge Corporation.

Core 230 is formed from numerous E-core and I-core sections 232 and 234 in the same manner as core 30 above. See FIGS. 12 and 14. These sections 232 and 234 include ferromagnetic materials such as 29 gauge, M6 grade steel. In the illustrated embodiment, each E-core section 232 is about 0.14 inches thick. Each I-core section 234 has a thickness of about 0.14 inches. The length Lc of the core 230 is about 2.25 inches, the thickness Tc of the core 230 is about 0.750 inches, and the height Hc of the core 230 is about 1.875 inches. See FIG. 1.

The primary windings 240a and 240b achieve a high degree of engagement between the primary windings 240a and 240b and the secondary windings 242a and 242b as well as the windings 240a, 240b and 242a and 242b. Interleaved with secondary windings 242a and 242b to minimize capacitance of the liver. Transformer 200 is very low to increase circuit 300's ability to receive lower level audio signals, increase primary inductance, reduce capacitive reactance, and increase overall frequency response of circuit 300. It is designed with magnetic flux density.

The first and second transformers 100 and 200 are connected to each other in series as illustrated in FIG. 8 to limit the passive circuit 300. The first hook-up or jumper wire 301, 24 gauge type (UL1007) lead wire is coupled to pin P ₅ of the first transformer 100 and pin P ₅ of the second transformer 200, and the second hook-up wire ( 303, a 24 gauge type UL1007 lead wire is coupled to pin P ₇ of the second transformer 200 and to pin P ₇ of the first transformer 100. 24 gauge lead wires are available from Belden Corporation.

The input of the passive circuit 300 may be directly coupled to an audio signal source S, for example a CD player, a DAT player, a laser disk player, a tape player, etc., and the output of the passive circuit 300 may be an audio amplifier, for example It can be directly coupled to the preliminary amplifier stage or the power amplifier stage. See FIG. 8. Any commercially available connector (s) can be used to connect the passive circuit 300 to a signal source including a single-ended connector or a balanced connector. No active element is connected between source S and audio amplifier A. When the transformers 100 and 200 are coupled in this manner, they are found to interact with each other so that when the input audio signal is transmitted therethrough the audio signals exhibit an improved harmonic quality compared to that of the original input audio signal.

In FIG. 15, first, second and third typical frequency response curves C ₁ , C ₂ , C ₃ generated by the passive circuit 300 constructed in accordance with the second embodiment are shown. For each curve, the output voltage is plotted against the frequency for the normalized input audio signals. The frequency response curves C ₁ , C ₂ , C ₃ are signal generators that generate a 1V input signal swept pin P ₁ of the first and second transformers 100 and 200 through a frequency band of about 20 Hz to about 22 KHz. When connected to signal source S and pin P ₁₁ of transformers 100 and 200 is connected to a conventional audio amplifier, its load exhibits 20 kW (curve C ₁₎ representing the equivalent impedance that transformers 100 and 200 can know. ), 25 kV (curve C ₂ ) and 100 kV (curve C ₃ ) to obtain a resistance rod. No active device intervened between the input source S and the resistive load.

Each of the first, second and second curves C ₁ , C ₂ , C ₃ is an input audio signal when an input audio signal passes through the passive circuit 300 and the output terminal of the passive circuit 300 is connected to a resistive load. It represents the amplification occurring for the frequency components of. The resistive rod is 20 kW for curve C ₁ , 50 kW for curve C ₂ , and 100 kW for curve C ₃ . For these three curves C ₁ , C ₂ , C ₃ , the input audio signal consisting of frequency components belonging to the frequency band having a lower limit and an upper limit appears to be distorted when transmitted through the passive circuit 300. This distortion is nonlinear amplification of the frequency components of the input audio signal. More specifically, the amplification of the frequency components of the input audio signal is at peak high frequencies (20 Hz, 50 at 20 Hz, about 2.0 KHz and 50 Hz and 100 Hz load at about 2.5 KHz and 3.5 KHz). Increasing at frequencies up to about 22 KHz for kHz and 100 Hz, and up to peak low frequencies (about 20 Hz for 20 Hz loads, about 800 Hz for 50 Hz loads, and about 1000 Hz for 100 Hz loads) at intermediate frequencies Increases with decreasing. Amplification of the frequency components at peak high frequency is about 2.0 to about 3.4. The amplification of the frequency components at the peak low frequency is about 1.9 to about 2.5. Thus, for curve C ₁ , the amplification of the frequency component at peak high frequency is about 1.8 times the amplification of the intermediate frequency component at 2 KHz, and the amplification of the frequency component at the peak low frequency is 1.7 times the amplification of the intermediate frequency component at 2 KHz. . For curve C ₂ , the amplification of the frequency component at the peak high frequency is about 1.8 times the amplification of the intermediate frequency component at 3 KHz, and the amplification of the frequency component at the peak low frequency is 1.3 times the amplification of the intermediate frequency component at 3 KHz. For curve C ₃ , the amplification of the frequency component at the peak high frequency is about 1.8 times the amplification of the intermediate frequency component at 3.5 KHz and the amplification of the frequency component at the peak low frequency is 1.4 times the amplification of the intermediate frequency component at 3.5 KHz.

The frequency response of the passive circuit 300 for a given load is as follows: the number of revolutions of the one or more coils 140, 142, 240, 242; The size and type of wire used to construct one or more coils 140, 142, 240, 242; DC resistance of one or more coils 140, 142, 240, 242; The shape and size of one or both of cores 130 and 230; And gauges and grades of materials used to form one or both of cores 130 and 230 may be varied. More specifically, the lower limit frequency response of the passive circuit 300 is for example 1) primary to secondary rotational ratio (ie, the first coil 140 and the combined rotation of the second coils 142 and 242). The rate of combined rotation of 240); 2) primary inductance controlled by the number of revolutions of the first and second coils 140, 142, 240, 242 and the gauge and grade of the material from which the cores 130 and 230 are made; 3) DC resistance of the coils 140, 142, 240, 242, the size and type of wire used to construct the coils 140, 142, 240, 242, and the coils 140, 142, 240, 242. Average length of each rotation; And 4) factors such as the signal source S and the impedance of the load. The upper frequency response of the passive circuit 300 may be, for example, 1) inter-winding capacitance, that is, capacitance between the first coil 140, 240 and the second coil 142, 242; 2) intra-winding capacitance, ie the capacitance between adjacent primary and secondary windings for each transformer 100 and 200; 3) placement of primary and secondary windings; And 4) factors such as the impedance of the signal source S and the load.

It is also believed that when the capacitance of the transformer 10 is changed, the amplification of the frequency components at the upper limit of the frequency band can be changed. Capacitance is the thickness of one or more film layers 151, 153, 155, 251, 253, 255; DC resistance of at least one winding 140a, 142a, 140b, 142b, 240a, 242a, 240b, 242b; And / or by changing the positions of the one or more windings 140a, 142a, 140b, 142b, 240a, 242a, 240b, 242b. It is believed that when the inductance of one or both of the transformers 100 and 200 is changed, the amplification of the frequency components at the lower limit of the frequency band can be changed. Inductance can be varied by changing the combined rotational speed of the first coils 140 and 240 and / or the gauge and grade of the material from which the cores 130 and 230 are made. Thus, empirical decisions are needed to accurately determine the configuration of transformers 100 and 200 in order to affect the desired frequency response when the transformers 100 and 200 are coupled to a given load.

Thus, according to the second embodiment of the present invention, the input signal is distorted into an augmented audio signal by passing the input audio signal through the passive circuit 300 to amplify the frequency components of the input signal. Amplification of the frequency components in the input audio signal increases as the frequency components increase at frequencies from the first intermediate or reference frequency to the peak high frequency and decrease at frequencies from the first intermediate or reference frequency to the peak low frequency. The first and second intermediate frequencies may be the same frequency or different frequencies. Above the peak high frequency, it may be desirable for the amplification to decrease as the frequency components increase at frequencies from the peak high frequency to the upper limit frequency. Below the peak low frequency, it may be desirable for the amplification to decrease as the frequency components decrease at frequencies from the peak low frequency to the lower limit frequency.

With respect to the second embodiment of the present invention, instead of those that are single frequencies, it is preferred that the peak high frequency, peak low frequency or both be relatively narrow range frequencies so that frequency components belonging to the narrow range generally have the same amplitude. It is expected to be desirable.

The peak high frequency may range from about 6KHz to about 30KHz. The amplification of the frequency component (s) at the peak high frequency may be about 1.5 to about 3.0 times the amplification of the first intermediate frequency. The peak low frequency may range from about 20 Hz to about 1 KHz. The amplification of the frequency component (s) at the peak low frequency may be about 1.25 times to about 2.0 times the amplification of the second intermediate frequency.

With regard to the first and second embodiments of the invention, it is envisaged that one or more transformers 10, 100 and 200 can be tapped. Tapping may occur during the winding of any of the first and second primary windings and any of the first and second secondary windings. After the predetermined rotational speed of the winding is wound around the bobbin and before the final rotational speed is formed, the wound wire can be connected to other pins of the bobbin. In the illustrated embodiment, the first transformer is tapped. After the third wire 150 is randomly wound 400 times around the second film layer 153, it is wound up or otherwise connected to pin P ₅ . Thereafter, the wire 150 is again wound 100 times and connected to the pin P ₆ . When the wire 301 is connected to the pin P ₅ , the effective second primary winding 140b includes 400 turns. Alternatively, when wire 301 is connected to pin P ₅ , the effective second primary winding 140b includes 500 turns. By varying the connection of wire 301 from pin P ₅ to P ₈ , the enhancement of the audio signal passing through passive circuit 300 is changed.

The enhanced audio signal according to the invention exhibits an improved harmonic quality compared to that of the original input audio signal. Additional advantages and modifications will be apparent to those skilled in the art. For example, two or more of the passive circuits, that is, two or more first passive circuits 5, two or more second passive circuits 300, or a combination of these passive circuits 5 and 300 may be used in series. It may be desirable.

Moreover, electronic audio signals from compact discs of music and voice are transmitted through the circuit of the present invention, and when the generated augmented electronic audio signals are rewritten onto a cassette tape using a consumer cassette player / recorder, they are recorded. The sound quality of music and voice generated from cassette tapes is perceived better than the same music and voice produced directly from compact discs. This even occurred when the compact disc format was widely recognized as producing superior sound quality compared to the cassette tape format.

The present invention enhances electronic audio signals from sound conversion equipment such as hearing aids, microphones, etc. before recording onto a recording medium (e.g., magnetic tape or optical disk) or before converting to acoustic sound or other sound impulses. It is believed that it can be used to make. Furthermore, the augmented audio signal according to the invention can be transmitted in the air or through some other medium, for example through the use of television, radio, sonar, computer or cellular telephones; Can be transmitted via transmission lines, eg, telephone, cable TV or computer use; Can be converted directly to audible sound for use in concerts, plays, restaurants, or bar pubs; It is believed that it can be used for any other purpose including audio signals, for example in distinguishing between cows, images and the like.

The passive circuit includes a single transformer that amplifies nonlinearly the frequency components of the input audio signal such that the amplification of the frequency components of the input audio signal increases as the frequency components decrease at intermediate frequencies, e.g., from 3.5 KHz to peak low frequencies. It is expected to be possible. It is believed that amplification of frequency components from about 3.5 KHz to about 20 KHz may have a single gain (1.0) below 1.0 or above 1.0. It is believed that the amplification of the frequency components at the peak low frequency may be about 1.25 to about 2.0 times the amplification of the intermediate frequency component or the average amplification of the range of intermediate frequency components belonging to the frequency band of 3.5 KHz to 20 KHz.

Accordingly, the invention is not to be limited in terms of the specific details, representative apparatus and methods, and examples shown and described herein. It is possible to start from such a detailed description without departing from the spirit or scope of the general inventive concept of the invention. Accordingly, the scope of the present invention should be limited only by the following claims or equivalents thereof.

Claims (23)

1. An input audio signal quality enhancing apparatus consisting of frequency components in a frequency band having an upper limit and a lower limit, comprising: amplifying frequency components of an input audio signal to distort the input signal into an enhanced audio signal when transmitted therethrough, the frequency component Passive circuit, in which the amplification of the frequency components of the input audio signal increases as they increase at frequencies from the first intermediate frequency to the peak high frequency, where the augmented audio signal exhibits an improved harmonic quality compared to that of the input audio signal. Input audio signal quality enhancement device comprising a. The apparatus of claim 1, wherein the peak high frequency ranges from about 6KHz to about 30KHz. The apparatus of claim 1, wherein the amplification of the frequency component at peak high frequency is about 1.5 to about 3.0 times the amplification of the intermediate frequency. 2. The passive circuit of claim 1, wherein the passive circuitry further distorts the input signal such that amplification of the frequency components of the input audio signal increases as the frequency components decrease at frequencies from the second intermediate frequency to the peak low frequency. And the audio signal exhibits an improved harmonic quality compared to that of the input audio signal. 5. The apparatus of claim 4, wherein the peak low frequency ranges from about 20 Hz to about 1.0 KHz. 5. The apparatus of claim 4, wherein the amplitude of the frequency component at peak low frequency is about 1.25 to about 2.0 times the amplification of the second intermediate frequency. 5. The apparatus of claim 4, wherein the first and second intermediate frequencies are the same frequency. 2. The apparatus of claim 1, wherein the passive circuit comprises at least one transformer. 9. The apparatus of claim 8, wherein the at least one transformer comprises a single transformer, the single transformer affecting the amplitude distortion of the input signal as defined by the first portion of the frequency response curve, Is nonlinearly increasing from the intermediate frequency to the peak high frequency. 9. The method of claim 8, wherein the at least one transformer comprises first and second transformers, wherein the first and second transformers are adapted to amplitude distortion of the input signal as defined by the first portion of the frequency response curve. Affecting, wherein the first portion increases nonlinearly from the first intermediate frequency to the peak high frequency and affects further amplitude distortion of the input signal as defined by the second portion of the frequency response curve. And the second portion nonlinearly increases from the second intermediate frequency to the peak low frequency. 11. The apparatus of claim 10, wherein the first and second intermediate frequencies are the same frequency. An audio source for generating an input audio signal consisting of frequency components in a frequency band having an upper limit and a lower limit; An audio amplifier for generating a speaker drive signal; And By amplifying the frequency components of the input audio signal so that the frequency components of the input audio signal increase as the frequency components increase at frequencies from intermediate to peak high frequencies, distorting the input signal into the augmented audio signal as it is transmitted through it. Wherein the augmented audio signal exhibits an improved harmonic quality of that of the input audio signal, comprising passive circuitry coupling the input audio signal to the audio amplifier. 13. The audio system of claim 12, wherein no active element is coupled between the audio source and the audio amplifier. 13. The system of claim 12, wherein the passive circuitry further distorts the input signal such that the frequency components of the input audio signal increase in amplitude as the frequency components decrease at frequencies from intermediate to peak low frequencies. The signal exhibiting an improved harmonic quality compared to that of the input audio signal. 13. The audio system of claim 12 wherein the passive circuit comprises at least one transformer. 16. The apparatus of claim 15, wherein the at least one transformer comprises a single transformer, the single transformer affecting the amplitude distortion of the input signal as defined by the first portion of the frequency response curve, Is nonlinearly increasing from the intermediate frequency to the peak high frequency. 16. The method of claim 15, wherein the at least one transformer comprises first and second transformers, wherein the first and second transformers are adapted to the amplitude distortion of the input signal as defined by the first portion of the frequency response curve. Affecting, the first portion increases nonlinearly from the intermediate frequency to the peak high frequency, affecting further amplitude distortion of the input signal as defined by the second portion of the frequency response curve Wherein said second portion increases nonlinearly from a second intermediate frequency to a peak low frequency. Providing an input audio signal consisting of frequency components in a frequency band having an upper limit and a lower limit; Distorting the input audio signal into an augmented audio signal by passing the input audio signal there through to amplify the frequency components of the input audio signal, as the frequency components increase at frequencies from intermediate to peak high frequencies. And wherein the amplification of the frequency components of the input audio signal is increased and the enhanced audio signal exhibits an improved harmonic quality compared to that of the input audio signal. 19. The method of claim 18, wherein the distortion step further comprises distorting the input signal such that amplification of the frequency components of the input audio signal increases as the frequency components decrease at frequencies from intermediate to peak low frequencies. Wherein the enhanced audio signal exhibits an improved harmonic quality of that of the input audio signal. 19. The method of claim 18, further comprising transmitting the augmented audio signal from one location to another. 19. The method of claim 18, further comprising processing the augmented audio signal into sound. 19. The method of claim 18, further comprising recording the augmented audio signal on a recording medium. A recording medium having recorded thereon at least one augmented audio signal by the method of claim 18.