Patent Description:
In a typical audio signal flow, the mobile performer uses a wireless microphone transmitter whose receiver output is processed by a monitor system and returned to the performer by means of loudspeakers or wireless personal monitoring systems such as in-ear monitors (IEM's). This allows the performer to hear themselves relative to other sounds (music, audience, room, etc.). Typical microphones used may be cardioid (unidirectional) or omnidirectional. Challenges to any such monitoring system may include: (i) system throughput latency (as discussed in <NPL>)); (ii) signal degradation (electronic, acoustic); (iii) gain before feedback; (iv) monitoring equipment complexity and reliability; (v) monitoring equipment expense; and/or (vi) monitor engineer training, consistency and expense.

In typical wearable sound systems, the user will have an audio reception device, such as, for example, a microphone, into which a sound is communicated. The signals representative of the sound are carried electronically through a transmission device. The transmitter will typically be connected either via wireless or wired means to a sound processing device, such as a sound board or post-processing system, where it is communicated back to an audio projection device, such as, for example, an earphone.

A byproduct of using the aforementioned sound systems is one or more of the following: reduction in vocal accuracy (e.g., pitch, and rhythm), vocal strain (e.g., oversinging), latency/delay between reception of sound and communication of sound to the user, feedback and other forms of noise/audio pollution, and increased number of products and intermediaries (e.g., personnel or equipment) needed to coordinate in the system.

Those of ordinary skill in the art would be familiar with the concept of latency, examples of which may be shown and described in the <NPL>), which is incorporated herein by reference in its entirety. Prior attempts to rectify the issue of latency in sound monitoring have proven ineffective, are cost-inefficient, and unable to solve the problem.

Referring to the illustrative embodiment of <FIG>, an audio source <NUM>, which may be a performer or other sound generator, utilizes a sound input mechanism known to those skilled in the art, such as, for example, a microphone <NUM>. According to this illustrative embodiment, a transmitter <NUM> is interconnected with microphone <NUM>. Where the system of <FIG> is utilized in theatrical applications, transmitter <NUM> may be worn on the body of performer <NUM> (such as, for example, a wireless device). Transmitter <NUM> may broadcast the signals from source <NUM> to a receiver <NUM>, which may be tuned to the transmitter <NUM> frequency. A monitoring entity <NUM>, which may be a monitor engineer, may operate an analog monitor sound console <NUM> to generate a desired audio output using the signal from receiver <NUM>. From analog monitor sound console <NUM> a signal may be sent to an audio output device <NUM>, which may be speakers or surround-sound systems, for example.

In operation, a system exemplified by <FIG> may provide a complete analog signal flow, which results in negligible latency from microphone <NUM> to output <NUM>, however, use of speakers (such as audio output <NUM>) in close proximity to microphone <NUM> will create feedback loop if the audio source I desires to hear their sound through output <NUM>. For example, in theatrical applications, a performer may desire to hear him or herself via monitor speakers. Another aspect of the system exemplified by Figure I is the need for a controller/monitor <NUM> separate and apart from source <NUM>, which is required in the post processing of output sound signals from source <NUM>. A consequence of use of a system according to Figure I is that the sound mix and volume will fluctuate as source I moves toward or away from output <NUM> and/or output <NUM> moves to and from source <NUM>.

According to the exemplary embodiment of <FIG>, an analog signal path may keep latency in the system to approximately zero time (e.g., <NUM>-<NUM> microseconds), although there may be latency in acoustic time measured from the distance of the sound transmission means <NUM> to the source <NUM>.

In practice, the proximity of the sound transmission means <NUM> to the sound transmission means I limits the effectiveness of the Figure I system configuration due to a potential feedback loop of the amplified sound signal returning to the sound transmission means <NUM>. Further, the monitor/controller <NUM> must be engaged in dynamic adjustment of the sound signal, which increases system participants and injects potentials for processing and other delays.

Referring to the illustrative embodiment of <FIG>, the source I may still utilize a sound transmission mechanism <NUM> to send sound to a transmitter <NUM>. As in a system exemplified by <FIG>, a transmitter <NUM> may transmit the sound signal to receiver <NUM>, which thereafter receives post-processing by a monitor/controller <NUM> via analog monitor sound console <NUM>. However, in the exemplary embodiment of <FIG>, a monitor transmitter <NUM> may broadcast the post-processed sound signal from analog monitor sound console <NUM> back to a receiver <NUM>, which like transmitter <NUM>, may be worn on the source <NUM>. An exemplary monitor transmitter <NUM> may be an in-ear monitor (IEM), which may be an earphone transducer connected to a wireless beltpack receiver designed to deliver audio information to the wearer. The transmitted, post-processed sound received at receiver <NUM> may then be delivered to source <NUM> via sound transmission means <NUM>, which may include, earphones, headsets, speakers, or other audio transmission mechanisms known to those skilled in the art.

In operation, a system exemplified by <FIG> may provide a complete analog signal flow, which results in negligible latency from microphone <NUM> to receiver <NUM>, however, the system of <FIG> must rely on the monitor/controller <NUM> separate and apart from source <NUM> and analog monitor sound console <NUM> for any corrective action on the audio signal. While the system exemplified by <FIG> may provide an analog, low-latency signal path in which feedback and acoustic latency are obviated by the elimination of the loudspeaker monitoring, it still requires monitor console equipment <NUM> and an monitor/controller <NUM> to operate, incurring additional costs and potential variability in sound processing.

Referring to the illustrative embodiment of <FIG>, a source <NUM> may still utilize a sound input mechanism <NUM> to send sound to a transmitter <NUM> and require post-processing before the signal from source <NUM> returns via a sound transmission means <NUM>. In contrast to a system exemplified by <FIG>, a system illustrated via <FIG> incorporates a digital monitor sound console 6A to handle post-processing of signals from source <NUM>. Consequently, a system illustrated by <FIG> will introduce levels of latency into the sound signal, which in certain cases may be between approximately <NUM> to approximately <NUM> of delay. As in the systems illustrated by <FIG> and <FIG>, the exemplary system of <FIG> also requires a monitor/controller <NUM> separate and apart from source <NUM> to correct the sound signal.

The system exemplified by <FIG> reflects the state of the art in audio processing architectures for use in performances in which most audio consoles in current use (including those used for monitoring) are digital. Introduction of digital components into the architecture come with the cost of added throughput latency to the monitoring system due to digital signal routing and processing. The sound source <NUM>, such as a performer, will begin to notice the effects of time delay through the system as the audio returns to their ear. Expected latency varies with equipment but can range from <NUM> to <NUM> and increases with the introduction of additional sound processing, either within the monitor console infrastructure or outboard signal processing equipment. As in the analog system configurations exemplified by <FIG> and <FIG>, the system configuration exemplified by <FIG> will also still typically require monitor console equipment <NUM> and an independent monitor/controller <NUM>.

Referring to the illustrative embodiment of <FIG>, a source <NUM> may still utilize a sound input mechanism <NUM> to send sound to a digital transmitter 4A, which broadcasts a digital wireless signal to receiver SA As in <FIG>, the processed digital wireless signal at receiver SA receives post-processing at digital monitor sound console 6A and monitor/controller <NUM> before the signal from source <NUM> returns via a sound transmission means <NUM>. In contrast to a system exemplified by <FIG>, a system exemplified by <FIG> introduces latency via the digital console 6A and transmitter 4A, which may be in certain cases between approximately <NUM> to approximately <NUM> of delay. As in the systems of <FIG>, <FIG>, and <FIG>, the system of <FIG> also requires a monitor/controller <NUM> separate and apart from source <NUM> to correct the sound signal.

The system exemplified by <FIG> provides for a common substitution of a digital wireless microphone system, which can introduce additional throughput latency in the monitoring system (resulting in <NUM> to <NUM>). For theatrical applications, throughput latency in the aforementioned range may be deemed unusable for the performers. As a further detriment to the system, an added digital monitor console 6A may further increase the latency time through the system and further disrupt and/or undermine the reliability of this monitoring solution. As was the case before, this exemplary system configuration as illustrated in <FIG> still typically requires monitor console equipment and an independent monitor/controller to operate.

Referring to the illustrative embodiment of <FIG>, a source <NUM> may still utilize a sound input mechanism <NUM> to send sound to a digital transmitter 4A, which broadcasts a digital wireless signal to receiver SA As in <FIG>, the processed digital wireless signal at receiver SA receives post-processing at digital monitor sound console 6A and monitor/controller <NUM>. Before returning to source <NUM> via a sound transmission means <NUM>, the sound signal is broadcast back through monitor <NUM> to a digital IEM receiver 8A at which point the IEM process the digitally post-processed signal prior to presentation to source <NUM> via means <NUM>. In contrast to a system exemplified by <FIG>, a system exemplified by <FIG> introduces latency via the digital console 6A and digital components (transmitter and receiver) 4A and SA, and <NUM> and 8A, which may be in certain cases between approximately <NUM> to approximately <NUM> of delay. As in the systems of <FIG>, <FIG>, <FIG>, and <FIG>, the system of <FIG> also requires a monitor/controller <NUM> separate and apart from source <NUM> to correct the sound signal.

Again, the exemplary system illustrated in <FIG> may include the introduction of additional digital wireless in-ear monitoring, which comes at a cost of additional throughput latency resulting in <NUM> to <NUM>. For theatrical applications, this range of latency is unacceptably high for a performer. As is the case in all prior art sound equipment systems, a monitor/controller <NUM> separate and apart from source <NUM> is required.

Consequently, the systems exemplified by <FIG> suffer from numerous deficiencies in terms of latency, increased resource utilization and/or additional controllers/monitors of the sound signal of the source, and/or redundancy in signal transmission components. <CIT> (<CIT>) discloses a wireless stage microphone system for a stage performer which allows monitoring of self-emitted sound with correction of latency-induced effects.

An audio enhancement system, comprises a microphone and a communication device for communicating the sound received at the microphone. An enhancement circuit coupling the microphone to the communication device may have a DC power source and a plurality of amplifiers in which at least one of the plurality of amplifiers is powered by the DC power source and at least one of the plurality of amplifiers receives a signal representative of the sound via its non-inverting input.

A method of audio enhancement comprises the steps of: transmitting audio signals to an enhancement circuit, transmitting enhanced audio signals to a user, and maintaining latency between audio signal transmission and enhanced audio signal transmission below approximately <NUM> where <NUM> is the expected latency and, for certain other applications where delays are approximately <NUM>, below that <NUM> threshold.

In the drawings like characters of reference indicate corresponding parts in the different figures. The drawing figures, elements and other depictions should be understood as being interchangeable and may be combined, modified, and/or optimized in any like manner in accordance with the disclosures and objectives recited herein as would be understood to those skilled in the art.

In an exemplary embodiment of the invention, a circuit may be employed to eliminate all latency in the system by amplifying the sound signal and returning it directly to the performer's ears entirely in the analog domain. Consequently, signal degradation may be substantially eliminated and the need for additional equipment-analog or digital-is obviated. A further benefit according to this exemplary embodiment is the removal of any additional monitor/controller 2from the system.

Referring to the illustrative embodiment of <FIG>, the sound source I may use a sound input mechanism <NUM> to transmit sound to an analog/digital transmitter <NUM>/4A to be received by an analog/digital receiver <NUM>/SA. Before transmission to analog/digital transmitter <NUM>/4A, the signal is received by a sound enhancement circuit, which may be exemplified by one or more of the embodiments related to or describing such an enhancement circuit I <NUM>, enhancement circuit <NUM>, or their combinations and/or equivalents in terms of architecture, components, or device specifications. A signal that is processed via an audio enhancement circuit I <NUM>/<NUM> may then be communicated back to the source I via sound transmission means <NUM>, which may include an earphone, headset, or like technology known to those skilled in the art.

Referring to the illustrative embodiments of <FIG> and <FIG>, the exemplary audio enhancement system used in the system exemplified by <FIG> may comprise an audio enhancement system I00 or 200A, which may comprise one or more circuits that take sound received from a receiver <NUM>, such as, for example, a microphone, and transmit the sound received through a transmitter <NUM>. An exemplary microphone <NUM> may be wearable via a clip, snap, adhesive, or other form of mechanical or chemical coupling mechanism known to those skilled in the art. An exemplary transmitter <NUM> may be of the type made and sold by Sennheiser electronic GmbH & Co. KG, ofWademark, Germany, Shure, Incorporated of Niles, Illinois, United States of America, Samsung Electronics, of Seoul, South Korea, and others known to those skilled in the art.

With reference to the circuit in system <NUM> depicted in the illustrative embodiment of <FIG>, an exemplary microphone <NUM> receives a sound which is transmitted to transmitter <NUM>. Thereafter, transmitter <NUM> communicates the signal to capacitive circuit element <NUM>, which is used for DC decoupling and low frequency limiting. A resistive circuit element <NUM> is connected as illustrated between circuit element <NUM> and ground so as to set input impedance and further reduce residual DC from the signal sent from the transmitter <NUM>. The remaining signal enters the non-inverting pin 118B of operational amplifier <NUM>.

Feedback signals from amplifier <NUM>, via the pin at 118A, may traverse resistive circuit element <NUM>, which may be found in parallel with a capacitor <NUM>. In this exemplary combination and configuration of components, the capacitor <NUM> may serve to dampen high frequencies.

Any gain achieved by amplifier <NUM> may be trimmed by resistive circuit elements <NUM>/<NUM>. The total gain of amplifier <NUM> may be limited by resistive circuit element <NUM>. In an exemplary embodiment the gain trimmer <NUM>/<NUM> may set the gain of the operational amplifier from O to +40dB.

The operational amplifier <NUM> may receive DC power (from source <NUM> illustrated in <FIG>, which may be, for example, a battery) at positive pin entry 112c and negative pin entry 112d. Resistive circuit elements <NUM> and <NUM> may act as decouplers for the positive and negative power supplies, respectively. Capacitive circuit elements <NUM> and <NUM> may lessen the noise from the DC power supply <NUM>.

The output of operational amplifier <NUM> passes through capacitive circuit element <NUM> to variable resistive element <NUM>. As illustrated, element <NUM> may act as a decoupling capacitor through which the signal from the operational amplifier <NUM> passes and enters the variable resistive element <NUM>, which may be, for example a volume control for the signal.

Upon receipt at variable resistive element <NUM>, the signal previously received may pass to the non-inverting input of operational amplifier <NUM>. Inputs 130a and 130b of amplifier <NUM> have no charge, while a feedback loop is established by way of path <NUM>. Resistive circuit element <NUM> acts to limit the maximum current of the signal output to the sound communication device <NUM>, which may be, for example, an earphone or ear bud. Capacitive element <NUM> may also provide for DC blocking and/or decoupling and may also reduce unwanted signal effects that may be damaging to the communication device <NUM>.

In a preferred embodiment, the relative values of each of the aforementioned circuit elements or their preferred implementations in an exemplary system <NUM> circuit may be provided in Table <NUM> below:.

A person of ordinary skill in the art would be able to substitute, modify, or design equivalents for any of the circuit components identified in system <NUM> circuit and further elaborated upon in Table <NUM> so as to provide substantially the same and/or comparable circuit component characteristics, such as, for example, equivalent resistance/induction/capacitance/impedance and/or current/voltage/power or other operational limitations.

With reference to the modification circuit <NUM> depicted in the illustrative embodiment of <FIG>, the circuit <NUM> may only be utilized when the voltage supply to the circuit of enhancement system <NUM> of <FIG> is above a predetermined value. For example, where switched-capacitor voltage converter <NUM> may be an ICL7660CSA, circuit <NUM> may only function, e.g., provide a low voltage at pin 150a, when voltages above 5V are supplied, but may be connected to ground for voltages below <NUM>. 5V (e.g., low voltage operation). When operational due to an achieved threshold supply voltage, circuit <NUM> comprises the switched-capacitor voltage converter <NUM> having multiple pins for various potential operations involving system <NUM> and power circuit <NUM> in <FIG>, respectively.

According to the illustrative embodiment of <FIG>, pin 150b may connect to a positive terminal of a charge-pump/reservoir capacitor <NUM>, while pin 150c may connect to the negative terminal of that same capacitor and/or may be connected to ground. Pin 150e may be connected to an external oscillator control input, such as, for example, a capacitor, whereby the input may reduce oscillator frequency. The capacitive circuit elements <NUM> and <NUM> may serve as further DC blocking/decoupling capacitors to lessen noise on the negative voltage line from pin 150d.

According to the illustrative embodiment of <FIG>, an exemplary power circuit <NUM> for use with the circuits in system <NUM> and/or with circuit <NUM>, either alone or in combination, may be shown. Circuit <NUM> may comprise the power source <NUM> for the circuit <NUM> and modification circuit <NUM>. A switch <NUM> may take any form known to persons of ordinary skill in the art. Fuse circuit element <NUM>, which may be, for example, a resettable poly fuse, may work in conjunction with diode <NUM>, to provide for reverse bias protection against the positive DC voltage from the power source <NUM>. As would be understood to a person of ordinary skill in the art, capacitive circuit elements <NUM> and <NUM> help to lessen audio frequencies on the DC input line from the power source <NUM>.

As further illustrated in the illustrative embodiment of <FIG>, a switched-capacitor voltage converters <NUM> may comprise a first pin 178A, which may be unconnected (e.g., be a designated "no connection"), a second pin 178B, which may be the positive voltage input and substrate connection, and a third pin 172c which may be the connection to ground.

In a preferred embodiment, the switched-capacitor voltage converter <NUM> and/or switched-capacitor voltage converter <NUM> of <FIG>, respectively, may be an ICL7660CSA type regulator offered by Mouser Electronics of Mansfield, Texas. Further, capacitive circuit elements <NUM>, <NUM>, and <NUM> may be <NUM> nanoFarads, <NUM> microFarads, and <NUM> microFarads, respectively. Capacitive circuit elements <NUM> and <NUM> may also be <NUM> nanoFarads and <NUM> microFarads, respectively. Power source <NUM> may also be a 9V battery.

In combination, the circuit of system <NUM>, circuit <NUM>, and circuit <NUM> may be used within a device <NUM>, as may be illustrated in <FIG>, to enhance the sound quality received at receiver <NUM> and transmitted by transmitter <NUM>. The device <NUM> can be used as a stand-alone adaptor or modification unit or be combined with the transmitter <NUM> as an enhancer-transmitter <NUM>. The device <NUM> may provide for adjustment mechanisms known to those skilled in the art, e.g., dial <NUM>, that may assist in delivering an enhanced sound to the communicator <NUM>. In an exemplary embodiment, use of device <NUM> in the sound system may allow the user of a wearable audio receiver <NUM> to obtain the same and/or enhanced audio on a wearable communicator <NUM> without the need for off-site audio processor equipment or personnel. Accordingly, device <NUM> and/or enhancer-transmitter <NUM> may reduce the need for further processing systems used to control audio quality of what is to be delivered by the communicator <NUM>. Those skilled in the art may recognize that enhancer-transmitter <NUM> may be designed so as to contain all sound receiving and sound communicating technologies in the system.

With reference to the enhancement circuit <NUM> depicted in the illustrative embodiment of <FIG>, an exemplary received sound signal from receiver <NUM> is transmitted via transmitter <NUM> to inductive circuit element <NUM> and capacitive circuit element <NUM>. Inductive circuit element <NUM> may aid in blocking RF frequencies while capacitive circuit element <NUM> may be used for DC decoupling and low frequency limiting. Resistive circuit element <NUM> may be used to set input impedance and/or bleed off residual DC voltage. The capacitive circuit element <NUM> may be used to complete the RF blockage in conjunction with the inductive circuit element <NUM>.

As an exemplary signal continues through circuit <NUM>, it may enter non-inverting pin 216b of operational amplifier <NUM>, which may be, for example, a low noise and stabile operational amplifier known to those skilled in the art. Similar to circuit <NUM>, a resistive circuit element <NUM> may act as a feedback resistor, which in combination with capacitive circuit element <NUM>, may contribute to high frequency roll off Similar to circuit <NUM>, a resistive circuit element <NUM> may act as a gain trimmer, which in a preferred embodiment, may set the gain of operational amplifier <NUM> from approximately O dB to approximately +<NUM> dB. Likewise, resistive circuit element <NUM> may limit the total gain for amplifier <NUM>. Similar to the configuration of resistive circuit elements <NUM> and <NUM> in the illustrative circuit <NUM> depicted in <FIG>, resistive circuit elements <NUM> and <NUM> may also act as decouplers for the positive and negative DC power supplies. In similar regard, capacitive circuit elements <NUM> and <NUM> may also lessen noise on the DC supply lines. As illustrated and aside from inverter and feedback pins, and the negative and positive voltage supplies, no further connections to operational amplifier <NUM> may be required to allow an exemplary circuit <NUM> to function in accordance with one or more of the objectives disclosed.

Further in the progression of a signal through circuit <NUM>, capacitive circuit element <NUM> may comprise a decoupling capacitor through which the signal passes to reach the variable resistive element <NUM>, which may, for example, be a front panel volume control and/or volume control wiper. An exemplary signal may pass from the variable resistive element <NUM> to the non-inverting inputs 250b and 270b of operational amplifiers <NUM> and <NUM>, respectively. One or both of operational amplifiers <NUM> and <NUM> may be a dual low noise operational amplifier known to those skilled in the art.

In an exemplary circuit <NUM>, the feedback loop for either of operational amplifiers <NUM> and <NUM> may comprise a current driver amplifier <NUM> and <NUM>, respectively. In a preferred embodiment, one or more of current driver amplifiers <NUM> and <NUM> may be a DRv134 operational amplifier known to those skilled in the art. The output/driver stages and/or the gain for current driver amplifier <NUM> may be set by a combination of resistive circuit elements <NUM> and <NUM>. The output/driver stages and/or the gain for current driver amplifier <NUM> may be set by a combination ofresistive circuit elements <NUM> and <NUM>. In a preferred embodiment, the output of the operational amplifier network formed by the operational amplifier <NUM>/<NUM> and its corresponding driver amplifier <NUM>/<NUM> may be increased by approximately <NUM> dB for a given stage. Capacitive circuit elements <NUM> and <NUM> may also roll off high frequencies in the operational amplifier network previously described.

In the exemplary circuit <NUM>, pins 250c and 250d may be positive and negative voltage supply regions, respectively, for operational amplifier <NUM>. Similarly, pins 270c and 270d may be positive and negative voltage supply regions, respectively, for operational amplifier <NUM>. Each of these operational amplifier's pins 250a and 270a, respectively, may serve as the conduits for the current driver amplifier feedback loop previously discussed. However, in contrast, the current driver amplifiers <NUM> and <NUM> do not have any connection at their input pins 255a and 275a but only receive the signal from operational amplifiers <NUM> and <NUM> via their non-inverting pins 255b and 275b, respectively. Further, each of the current driver amplifiers <NUM> and <NUM> has a positive voltage supply pin 255c and 275c, respectively, and a negative voltage supply pin 255d and 275d, respectively.

As previously disclosed with respect to an exemplary circuit <NUM>, a DC blocking and/or decoupling function may be achieved at both ends of the amplifier networks using, for example, a capacitive circuit element <NUM>/<NUM> to provide protection to the sound communication equipment, which may be, for example, ear phones <NUM>/<NUM>.

Fuse devices <NUM> and <NUM> may also be incorporated into the design of an exemplary circuit <NUM> to provide further limits on maximum current of the signal that may reach the communication equipment. Fuse devices <NUM>/<NUM> may be resettable after occurrence of a fault. In an exemplary embodiment, an audio signal traversing circuit <NUM> may be routed to an eight inch/<NUM>. 5mmjack, whereby two communication devices may each be driven by the same power source but using separate current driving amplifiers.

In a preferred embodiment, the relative values of each of the aforementioned circuit elements or their preferred implementations in an exemplary circuit <NUM> may be provided in Table <NUM> below:.

A person of ordinary skill in the art would be able to substitute, modify, or design equivalents for any of the circuit components identified in circuit <NUM> and further elaborated upon in Table <NUM> so as to provide substantially the same and/or comparable circuit component characteristics, such as, for example, equivalent resistance/induction/capacitance/impedance and/or current/voltage/power or other operational limitations.

With reference to the illustrative embodiment of <FIG>, an exemplary power circuit <NUM> may have a power source <NUM>, such as a lithium 9V type battery, which may be <NUM> to <NUM> volts when charged, may have its minus terminal attached to ground and its plus terminal to switch <NUM>. Switch <NUM> may take the form of a lever-and-hinge construct or may be a rotational section of a knob or dial (e.g., dial <NUM> as illustrated in <FIG>). In an exemplary embodiment, the knob that may control volume on the device housing circuit 200A may also be part of the switch <NUM> mechanism for circuit 200A. The positive DC voltage goes through a fuse element <NUM>, which may be a resettable polyfuse, to diode element <NUM>, which may be a reverse bias protection part of circuit 200A. Capacitive circuit elements <NUM> and <NUM> may aid in reducing audio frequencies on the DC voltage input line.

The positive voltage enters linear voltage regulator <NUM> at input 266a. In an exemplary embodiment, the voltage going to regulator <NUM> is approximately <NUM> Volts and the regulator is a linear +<NUM> volt regulator. To protect the regulator <NUM>, a diode element <NUM> may be situated at output 266c. Each of capacitive circuit elements <NUM>, <NUM>, and <NUM> may act to filter DC voltage, stabilize the DC voltage signal, or a combination thereof.

The voltage that enters a DC conversion device <NUM>, which may be a DC-DC SM device, such as the kind offered by Mouser Electronics of Mansfield, Texas. Device <NUM> may convert the incoming voltage to another voltage, for example a positive <NUM> V DC to a positive and/or negative <NUM> V DC. As depicted, device <NUM> uses pins 288b and 288c as ground to which regulator <NUM> output pin 266b may also be connected. Input pin 288a may receive the output voltage from regulator <NUM>, while output pins 288d and 288e may provide positive and negative DC voltage to power the amplifiers <NUM>, <NUM>, <NUM>, <NUM> in circuit <NUM>.

Input 266a ofregulator <NUM> may also be connected to Zener diode element <NUM> specified to a particular DC voltage. In a preferred embodiment, Zener diode element may be specified as <NUM>V DC. Upon passing Zener diode <NUM>, the DC voltage may pass through resistive element <NUM> to the base of an NPN transistor <NUM> and pass through resistive element <NUM>. In an exemplary embodiment, NPN transistor <NUM> may act as a switch while the resistive element <NUM> bleeds off the DC voltage to ground, which is to where NPN transistor <NUM> emitter is coupled. The collector ofNPN transistor <NUM> may be connected to resistive elements <NUM> and <NUM>, which make for a signaling arrangement with LED 299a to indicate when power is applied and nominal voltage is satisfactory. As illustrated in <FIG>, resistive element <NUM> may be coupled to the cathode of LED 299a, while the positive voltage of the power source <NUM> may be connected to the anode of LED 299a.

The voltage traveling through resistive element <NUM> may also enter the base ofNPN transistor <NUM>, which may also act as a switch. The emitter of the NPN transistor <NUM> may be coupled to ground while the collector connects to resistive element <NUM>, which like resistive element <NUM>, may further limit the current. Simultaneously, resistive element <NUM> may be connected to the cathode of with LED 299b and the positive voltage of the power source <NUM> may be connected to the anode of LED 299b. Accordingly, if the power source <NUM> may have a voltage below a predetermined threshold, one of LED 299a or 299b may alight. Lighting of one or LED 299a or 299b may indicate replacement of or further need for additions to the power source <NUM>.

In an exemplary embodiment, the power source <NUM> may still allow for the system to work if the voltage remains above a certain threshold. In a preferred embodiment, an exemplary system using a circuit such as <NUM> and 200A may utilize a lithium battery to charge the system so long as the battery voltage is above approximately <NUM>. In an exemplary embodiment, the time between recharge events for the particular circuits of <NUM> and 200A may be approximately <NUM> hours.

In a preferred embodiment, the relative values of each of the aforementioned circuit elements or their preferred implementations in an exemplary circuit 200A may be provided in Table <NUM> below:.

A person of ordinary skill in the art would be able to substitute, modify, or design equivalents for any of the circuit components identified in circuit 200A and further elaborated upon in Table <NUM> so as to provide substantially the same and/or comparable circuit component characteristics, such as, for example, equivalent resistance/induction/capacitance/impedance and/or current/voltage/power or other operational limitations.

In an exemplary embodiment, the power sources <NUM>/<NUM> of the systems <NUM>/<NUM> and their corresponding circuits <NUM>, <NUM>, and 200A, respectively, may be combined with or shared with the transmitter, receiver, and/or the communicator. For example, the same battery used to keep charged the transmitter may also be used to keep an exemplary audio enhancement circuit alive. Additionally, exemplary enhancement circuits, like those illustratively provided by the circuits <NUM>/<NUM>, and any suitable communicator, receiver, and transmitter may be housed in a single device to reduce space needs. In a preferred embodiment, an enhancement circuit, like those illustratively provided in system <NUM>/<NUM>, may be utilized in one or more of the following: mobile communication devices (cell phones, iPhone, personal data assistants), hearing aids/assist, microphone and speaker systems for telecommunications, online gaming, and military applications, and in computer systems configured to allow for online communications between users via platforms such as Face-Time, Webinars, Skype chats, and other variants as known to those skilled in the art.

In a preferred embodiment, the disclosed systems and devices may be utilized as part of an in-ear monitoring system used in theatrical performances by thespians. In such an embodiment, the audio enhancement system may be attached inconspicuously to the wearer while the headphone is elsewhere hidden but otherwise connected to the audio enhancement system. After the user speaks into the microphone during the performance the transmitter would send the sound through the audio enhancement system to enable the thespian to reduce the need for off-stage treatment of the sound signals received, preserve vocal quality and strength, and encourages natural voice production.

In another alternative embodiment, an exemplary audio enhancement system <NUM> and/or <NUM>, such as those systems illustratively provided in <FIG>, <FIG> and/or 8B, may be integrated into a pre-existing circuit architecture for an audio transmitting device, including being embedded as an integrated circuit, provided the presence of an earphone amplifier as illustratively provided for in <FIG> and <FIG>.

In the exemplary embodiment of an exemplary audio enhancement system embedded in audio transmitting device illustratively provided for in <FIG>, the sound source <NUM> may use a sound input mechanism <NUM> to transmit sound to an analog/digital or analog/analog transmitter with embedded audio enhancement system therein (collectively, enhanced transmitter 4C). The sound is then transmitted from the transmitter 4C to an analog/digital receiver <NUM>/SA. According to this illustrative embodiment, the transmitter 4C provides local output for monitoring, which has the benefit of providing an exemplary zero latency (e.g., <NUM>-<NUM> microseconds) between microphone <NUM> and sound source <NUM>. Consequently, no monitor engineer or console is required for sound source <NUM> to control the quality and character of the sound input into mechanism <NUM>.

In the exemplary embodiment of an exemplary audio enhancement system embedded in audio transmitting device illustratively provided for in <FIG>, exemplary components of audio enhancement systems <NUM> and 200A, as illustratively provided for in <FIG> and <FIG>, respectively, and described herein, may be embedded in an transmitter 4C. In contrast to the audio enhancement systems of <FIG> and <FIG>, transmitter 4C contains its own microphone <NUM>, battery and/or power source <NUM>, microphone amplifier <NUM>, DC/DC converter <NUM>, and control switch <NUM>. According to this exemplary embodiment illustrated in <FIG>, microphone <NUM> belonging to transmitter 4C may take in sound signals for amplification by microphone amplifier <NUM>. In an exemplary embodiment, microphone amplifier <NUM> may be a constituent a wireless or RF transmitter. The power source <NUM> may be used to power the other components in the audio enhancement systems <NUM> and 200A, such as, for example microphone amplifier <NUM>, regulator <NUM>, and device <NUM>,. In the portion of transmitter 4C proximal to microphone <NUM>, the audio output of microphone amplifier <NUM> may be fed into enhancement circuit system <NUM> as well as to other components via line <NUM> (e.g., the audio stage of a transmitter such as a Sennheiser SK50 Wireless Transmitter).

In another exemplary embodiment of transmitter 4C, a control switch <NUM> may be a hardware switch or a software-controlled switch that can either activate or inactivate enhancement circuit system <NUM> and/or 200A. In an exemplary embodiment, control switch <NUM> may be designed to reduce energy consumption by one or more components in enhancement circuit systems <NUM>, 200A, or a combination of both and/or combination of components in each, e.g., power consumption by device <NUM> and amplifiers <NUM>/<NUM>/<NUM>/<NUM>/<NUM>. In a further exemplary embodiment of transmitter 4C, power from power source <NUM>, e.g. a battery, may also be used to power other components via line <NUM> of transmitter 4C, such as, for example, microphone amplifier <NUM>, system <NUM>, the RF and audio sections of the transmitter 4C. According to the foregoing exemplary embodiments, the transmitter portion of enhanced transmitter 4C may be a Sennheiser SK50 transmitter sold and made by Sennheiser Electronic GmbH & Co. KG, ofWademark, Germany or other commercially available transmitters known to those skilled in the art.

Claim 1:
An audio enhancement system for enhancing an audio signal from a sound source such as a user (<NUM>) using a sound input mechanism (<NUM>) such as a microphone (<NUM>) to generate said audio signal, the audio enhancement system comprising: a transmitter (<NUM>, <NUM>/4A, 4C) configured to receive the audio signal, wherein the audio signal is transmitted from the transmitter to a receiver (<NUM>/5A) and an audio enhancement circuit (<NUM>, <NUM>) configured to receive the audio signal, the audio enhancement circuit comprising:
a decoupling circuit element (<NUM>,<NUM>) electrically connecting the audio signal from the sound receiving source connected in series to a non-inverting input of a first amplifier (<NUM>, <NUM>) powered by a DC voltage;
a variable resistor (<NUM>, <NUM>) by which the audio signal travels along an electrical connection from the first amplifier to a second amplifier (<NUM>),
wherein the second amplifier is electrically coupled to a feedback loop, the second amplifier being further electrically coupled at its output to a sound transmission means (<NUM>, <NUM>) to output an enhanced sound back to the sound source (<NUM>).