Speech enhancement apparatus and respirator mask comprising the same

Abstract

A speech enhancement apparatus configured for attachment to a respirator mask is disclosed. The speech enhancement apparatus includes a first microphone configured to detect acoustic energy within a clean air envelope, a second microphone configured to detect acoustic energy outside of the clean air envelope, a speaker, and a controller operably coupled to the first microphone, the second microphone, and the speaker. The controller is configured to determine a speech signal based at least on a first signal generated by the first microphone. The controller is further configured to determine an ambient sound signal based on a second signal generated by the second microphone. The controller is further configured to process the speech signal and the ambient sound signal to generate a processed output signal configured to cause the speaker to emit acoustic energy, and deliver the processed output signal to the speaker.

Description

[0001] SPEECH ENHANCEMENT APPARATUS AND RESPIRATOR MASK COMPRISING THE

[0002] SAME

[0003] Technical Field

[0004] The present disclosure generally relates to a speech enhancement apparatus and a respirator mask including the speech enhancement apparatus.

[0005] Background

[0006] Respirator masks are used in a wide variety of environments, such as paint booths, grain storage facilities, laboratories with hazardous biological materials, environments containing certain chemical fumes, etc. However, respirator masks may detrimentally affect the intelligibility of the speech of users wearing the respirator masks.

[0007] Summary

[0008] In a first aspect, the present disclosure provides a speech enhancement apparatus configured for attachment to a respirator mask. The speech enhancement apparatus includes a first microphone. The first microphone is configured to detect acoustic energy within a clean air envelope of the respirator mask. The first microphone is further configured to generate a first signal indicative of the acoustic energy detected by the first microphone. The speech enhancement apparatus further includes a second microphone. The second microphone is configured to detect acoustic energy outside of the clean air envelope of the respirator mask. The second microphone is further configured to generate a second signal indicative of the acoustic energy detected by the second microphone. The speech enhancement apparatus further includes a speaker configured to produce acoustic energy outside of the clean air envelope. The speech enhancement apparatus further includes a controller operably coupled to the first microphone, the second microphone, and the speaker. The controller is configured to receive the first signal from the first microphone. The controller is further configured to determine a speech signal based at least on the first signal. The speech signal is indicative of a speech of a user wearing the respirator mask. The controller is further configured to receive the second signal from the second microphone. The controller is further configured to determine an ambient sound signal based on the second signal. The ambient sound signal is indicative of acoustic energy outside of the clean air envelope. The controller is further configured to process the speech signal and the ambient sound signal to generate a processed output signal. The processed output signal is configured to cause the speaker to emit acoustic energy. The controller is further configured to deliver the processed output signal to the speaker.

[0009] In a second aspect, the present disclosure provides a respirator mask. The respirator mask includes a mask body configured to define a clean air envelope between the mask body and a mouth and a nose of a user wearing the respirator mask. The respirator mask further includes a speech enhancement apparatus. The speech enhancement apparatus includes a first microphone. The first microphone is configured to detect acoustic energy within the clean air envelope of the respirator mask. The first microphone is further configured to generate a first signal indicative of the acoustic energy detected by the first microphone. The speech enhancement apparatus further includes a second microphone. The second microphone is configured to detect acoustic energy outside of the clean air envelope of the respirator mask. The second microphone is further configured to generate a second signal indicative of the acoustic energy detected by the second microphone. The speech enhancement apparatus further includes a speaker configured to produce acoustic energy outside of the clean air envelope. The speech enhancement apparatus further includes a controller operably coupled to the first microphone, the second microphone, and the speaker. The controller is configured to receive the first signal from the first microphone. The controller is further configured to determine a speech signal based at least on the first signal. The speech signal is indicative of a speech of the user wearing the respirator mask. The controller is further configured to receive the second signal from the second microphone. The controller is further configured to determine an ambient sound signal based on the second signal. The ambient sound signal is indicative of acoustic energy outside of the clean air envelope. The controller is further configured to process the speech signal and the ambient sound signal to generate a processed output signal. The processed output signal is configured to cause the speaker to emit acoustic energy. The controller is further configured to deliver the processed output signal to the speaker.

[0010] The details of one or more examples of the disclosure are set forth in the accompanying drawings and the description below. Other features, objects, and advantages of the disclosure will be apparent from the description and drawings, and from the claims.

[0011] Brief Description of the Drawings

[0012] Exemplary embodiments disclosed herein may be more completely understood in consideration of the following detailed description in connection with the following figures. The figures are not necessarily drawn to scale. Like numbers used in the figures refer to like components. However, it will be understood that the use of a number to refer to a component in a given figure is not intended to limit the component in another figure labeled with the same number.

[0013] FIG. 1 is an exploded front perspective view of a respirator mask including a speech enhancement apparatus according to an embodiment of the present disclosure;

[0014] FIG. 2 is a rear perspective view of the speech enhancement apparatus of FIG. 1 according to an embodiment of the present disclosure;

[0015] FIG. 3 is a schematic diagram of the respirator mask according to an embodiment of the present disclosure; and

[0016] FIG. 4 is a block diagram of the speech enhancement apparatus according to an embodiment of the present disclosure. Detailed Description

[0017] In the following description, reference is made to the accompanying figures that form a part thereof and in which various embodiments are shown by way of illustration. It is to be understood that other embodiments are contemplated and may be made without departing from the scope or spirit of the present disclosure. The following detailed description, therefore, is not to be taken in a limiting sense.

[0018] In the following disclosure, the following definitions are adopted.

[0019] As recited herein, all numbers should be considered modified by the term “about”. As used herein, “a,” “an,” “the,” “at least one,” and “one or more” are used interchangeably.

[0020] As used herein as a modifier to a property or attribute, the term “generally”, unless otherwise specifically defined, means that the property or attribute would be readily recognizable by a person of ordinary skill but without requiring absolute precision or a perfect match (e.g., within + / - 20 % for quantifiable properties).

[0021] The term “substantially”, unless otherwise specifically defined, means to a high degree of approximation (e.g., within + / - 10% for quantifiable properties) but again without requiring absolute precision or a perfect match.

[0022] The term “about”, unless otherwise specifically defined, means to a high degree of approximation (e.g., within + / - 5% for quantifiable properties) but again without requiring absolute precision or a perfect match.

[0023] Terms such as same, equal, uniform, constant, strictly, and the like, are understood to be within the usual tolerances or measuring error applicable to the particular circumstance rather than requiring absolute precision or a perfect match.

[0024] As used herein, the terms “first” and “second” are used as identifiers. Therefore, such terms should not be construed as limiting of this disclosure. The terms “first” and “second” when used in conjunction with a feature or an element can be interchanged throughout the embodiments of this disclosure.

[0025] As used herein, when a first material is termed as “similar” to a second material, at least 90 weight % of the first and second materials are identical and any variation between the first and second materials includes less than about 10 weight % of each of the first and second materials.

[0026] As used herein, “at least one of A and B” should be understood to mean “only A, only B, or both A and B”.

[0027] Unless specified or limited otherwise, the terms “attached,” “connected,” “coupled,” and variations thereof, are used broadly and encompass both direct and indirect attachments, connections, and couplings.

[0028] As used herein, the term “fixedly attached” when used in conjunction with two components, refers to an attachment of the two components that does not allow separation of the two components without destruction or deformation of at least one of the two components.

[0029] As used herein, the term “configured to” and like is at least as restrictive as the term “adapted to” and requires actual design intention to perform the specified function rather than mere physical capability of performing such a function. As used herein, the term “digital signal processor” or “DSP” refers to any circuitry or procedure being capable of processing several digital signal portions to generate or assemble a global digital output signal. This processing may include constructing the global digital output signal based on contributions of the input signals in accordance with an algorithm.

[0030] As used herein, the term “filtering” in the context of one or more signals refers to operations performed so as to adjust, change, or modify the one or more signals. Such operations may eliminate or reduce signal degradation caused by noise and delay jitter. A signal-filtering process does not alter the content of the original signal.

[0031] As used herein, the term “noise” refers to unwanted acoustic or vibration energy captured by a microphone or a bone conduction sensor.

[0032] As used herein, the term “bone conduction sensor” refers to a sensor or a device that converts vibrations of a bone (e.g., the skull) into a signal. As one example, a bone conduction sensor may be placed at various positions on the skull of a user to generate a signal indicative of a speech of the user.

[0033] According to one aspect, the present disclosure provides a speech enhancement apparatus configured for attachment to a respirator mask. The speech enhancement apparatus includes a first microphone. The first microphone is configured to detect acoustic energy within a clean air envelope of the respirator mask. The first microphone is further configured to generate a first signal indicative of the acoustic energy detected by the first microphone. The speech enhancement apparatus further includes a second microphone. The second microphone is configured to detect acoustic energy outside of the clean air envelope of the respirator mask. The second microphone is further configured to generate a second signal indicative of the acoustic energy detected by the second microphone. The speech enhancement apparatus further includes a speaker configured to produce acoustic energy outside of the clean air envelope. The speech enhancement apparatus further includes a controller operably coupled to the first microphone, the second microphone, and the speaker. The controller is configured to receive the first signal from the first microphone. The controller is further configured to determine a speech signal based at least on the first signal. The speech signal is indicative of a speech of a user wearing the respirator mask. The controller is further configured to receive the second signal from the second microphone. The controller is further configured to determine an ambient sound signal based on the second signal. The ambient sound signal is indicative of acoustic energy outside of the clean air envelope. The controller is further configured to process the speech signal and the ambient sound signal to generate a processed output signal. The processed output signal is configured to cause the speaker to emit acoustic energy. The controller is further configured to deliver the processed output signal to the speaker.

[0034] The speech enhancement apparatus of the present disclosure may improve the intelligibility of the speech of the user wearing the respirator mask. Specifically, the processed output signal generated by the controller (by processing the speech signal and the ambient sound signal) may be filtered, have reduced noise or an improved signal to noise ratio (SNR) than that of the speech signal, improved speech transmission index (STI) than the speech signal, a greater or smaller amplitude than the speech signal, and may generally be a cleaner signal than the speech signal. As a result, when the speaker emits acoustic energy based on the processed output signal, the speech of the user that is heard outside of the respirator mask may be of higher quality and improved intelligibility. The controller may utilize the second microphone to improve the speech signal.

[0035] As a result, the acoustic energy emitted by the speaker due to the processed output signal may provide improved intelligibility of the speech of the user wearing the respirator mask. The speech enhancement apparatus may therefore be suitable for use in noisy environments. In some examples, the controller may further utilize a bone conduction sensor of the speech enhancement apparatus for further improving the processed output signal.

[0036] Referring now to the figures, FIG. 1 illustrates a respirator mask 10 according to an embodiment ofthe present disclosure. The respirator mask 10 includes a mask body 12. The mask body 12 is configured to define a clean air envelope between the mask body 12 and a mouth and a nose of a user wearing the respirator mask 10.

[0037] The mask body 12 may form a seal at its periphery with the face of the user. Specifically, the respirator mask 10 may include sealing materials attached proximal to the periphery of the mask body 12 to contact the skin of the user to form a seal therewith. The mask body 12 may be formed of a material that is selected to be substantially impermeable to the types of airborne environmental hazards to which the respirator mask 10 is designed to offer a barrier. The respirator mask 10 may include filters 14 for filtering air entering the respirator mask 10 as the user inhales. The filters 14 may be of any suitable type, and the present disclosure is not limited thereto . The respirator mask 10 may also include straps or other attachment structures to retain the respirator mask 10 in position on the face of the user. Such straps or other attachment structures are not depicted in FIG. 1 for illustrative purposes.

[0038] The respirator mask 10 may further include an exhalation port 17 and a flexible diaphragm (not shown) located in the exhalation port 17. The flexible diaphragm may open in response to an increase in pressure in the clean air envelope of the mask. Alternatively, the respirator mask 10 may include various other exhalation ports and diaphragms located therein.

[0039] The respirator mask 10 may be a negative pressure respirator mask or a positive pressure respirator mask. Furthermore, although the respirator mask 10 is depicted as a partial facepiece respirator mask, the respirator mask 10 may alternatively be a full facepiece respirator mask.

[0040] As discussed above, the mask body 12 is configured to define the clean air envelope between the mask body 12 and the mouth and the nose ofthe user wearing the respirator mask 10. The clean air envelope may be defined, in large part, by the mask body 12 of respirator mask 10 and any seal extending around the edges or periphery of the mask body 12. The inhalation ports to which the filters 14 are attached, along with the exhalation port 17, may also define the clean air envelope.

[0041] The respirator mask 10 further includes a speech enhancement apparatus 20. The speech enhancement apparatus 20 is configured for attachment to the respirator mask 10. In some embodiments, the speech enhancement apparatus 20 may be configured for removable (or selective) attachment to the respirator mask 10. In some other embodiments, the speech enhancement apparatus 20 may be fixedly attached to the respirator mask 10. The respirator mask 10 may further include a port 18 located on the mask body 12. In some embodiments, the port 18 may open directly into the clean air envelope defined by the respirator mask 10 so that any speech energy emitted within the clean air envelope can reach the speech enhancement apparatus 20 directly.

[0042] Referring now to FIGS. 1 and 2, the speech enhancement apparatus 20 may include a housing 22 configured for attachment to the port 18 of the respirator mask 10. The housing 22 may include a fitting 24 configured for selective attachment to the port 18 of the respirator mask 10. The fitting 24 is depicted in the form of a flange in FIG. 2. The fitting 24 may include ears 26 that may be configured to fit within slots 19 in the port 18, such that rotation of the housing 22 about an axis 21 locks the speech enhancement apparatus 20 in place within the port 18.

[0043] The construction of the fitting 24, the ears 26, and the port 18 (along with the slots 19) may provide a bayonet type fitting for attachment of the speech enhancement apparatus 20 to the respirator mask 10. Many other bayonet type fitting structures may be used in place of those depicted in FIGS. 1 and 2. Further, many other attachment structures may be used to selectively attach the speech enhancement apparatus 20 to the respirator mask 10. Examples of some potentially suitable alternative attachment structures configured for selective attachment include, but are not limited to, threaded structures, detent mechanisms, straps, and the like.

[0044] FIG. 3 illustrates a schematic diagram of the respirator mask 10 according to an embodiment of the present disclosure.

[0045] Referring to FIGS. 1 to 3, the speech enhancement apparatus 20 includes a first microphone 34. The first microphone 34 is configured to detect acoustic energy within a clean air envelope 15 of the respirator mask 10. As discussed above, the clean air envelope 15 of the respirator mask 10 may be at least partially defined by the mask body 12. The first microphone 34 may be of any suitable type. For example, the first microphone 34 may be a diaphragm microphone, a MEMS microphone, a pre-polarized microphone, an electret microphone, and so forth.

[0046] The speech enhancement apparatus 20 further includes a second microphone 40 (schematically depicted by a circle in FIG. 1). The second microphone 40 is configured to detect acoustic energy outside of the clean air envelope 15 of the respirator mask 10. In other words, the second microphone 40 may be configured to detect acoustic energy in an ambient environment 16 surrounding the respirator mask 10. The second microphone 40 may be of any suitable type. For example, the second microphone 40 may be a diaphragm microphone, a MEMS microphone, a pre-polarized microphone, an electret microphone, and so forth. In some embodiments, at least one of the first microphone 34 and the second microphone 40 is selected from the list consisting of a diaphragm microphone, a MEMS microphone, a pre-polarized microphone, and an electret microphone.

[0047] The speech enhancement apparatus 20 further includes a speaker 46. The speaker 46 is configured to produce acoustic energy outside of the clean air envelope 15. In other words, the speaker 46 may be configured to produce acoustic energy in the ambient environment 16. The speaker 46 may be of any suitable type. For example, the speaker 46 may be an electro-magnetic or a magneto-electric transducer. As depicted in FIGS. 1 and 2, the first microphone 34 and the second microphone 40 may be located in the housing 22. Furthermore, the speaker 46 may be located in the housing 22. The speech enhancement apparatus 20 may further include one or more vibration isolation members (not shown) located in the housing 22. Specifically, the speech enhancement apparatus 20 may include a first vibration isolation member disposed between the housing 22 and the first microphone 34, a second vibration isolation member disposed between the housing 22 and the second microphone 40, and a third vibration isolation member disposed between the housing 22 and the speaker 46.

[0048] The speech enhancement apparatus 20 further includes a controller 30 operably coupled to the first microphone 34, the second microphone 40, and the speaker 46. The controller 30 may include, for example, one or more microprocessors, Field-Programmable Gate Arrays (FPGA), Digital Signal Processors (DSP), microcontrollers, Application Specific Integrated Circuit (ASIC) state machines, etc. As will be discussed in greater detail below, the controller 30 may be configured to perform digital sound processing / filtering based on inputs from the first microphone 34, the second microphone 40, and other components of the speech enhancement apparatus 20. In some embodiments, the controller 30 may be located in the housing 22.

[0049] The speech enhancement apparatus 20 may further include a power source 32 operably connected to the controller 30. The power source 32 may be configured to power the controller 30, as well as other components of the speech enhancement apparatus 20 connected to the controller 30. For example, the power source 32 may power the first microphone 34, the second microphone 40, and / or the speaker 46.

[0050] In some embodiments, the power source 32 is rechargeable. The power source 32 may be a secondary battery, for example. However, in some other embodiments, the power source 32 may be non- rechargeable. In some embodiments, the power source 32 may be replaceable. It may be noted that the power source 32 may be provided in any number of a variety of different forms, including for example, batteries, capacitors, etc.

[0051] The speech enhancement apparatus 20 may further include a switch 48 operably connected to the controller 30. The switch 48 may be configured to change an operational state of the speech enhancement apparatus 20. For example, the switch 48 may be configured to turn on or turn off the speech enhancement apparatus 20. As shown in FIG. 1, the switch 48 may be located on the housing 22 such that it is easily accessible to the user wearing the respirator mask 10.

[0052] FIG. 4 illustrates a block diagram of the speech enhancement apparatus 20 according to an embodiment of the present disclosure.

[0053] Referring to FIGS. 3 and 4, as discussed above, the first microphone 34 is configured to detect the acoustic energy within the clean air envelope 15 of the respirator mask 10. The first microphone 34 is further configured to generate a first signal 36 indicative of the acoustic energy detected by the first microphone 34.

[0054] Furthermore, as discussed above, the second microphone 40 is configured to detect the acoustic energy outside of the clean air envelope 15 of the respirator mask 10. The second microphone 40 is further configured to generate a second signal 42 indicative of the acoustic energy detected by the second microphone 40.

[0055] The controller 30 is configured to receive the first signal 36 from the first microphone 34. The controller 30 is configured to determine a speech signal 38 based at least on the first signal 36. The speech signal 38 is indicative of a speech of the user wearing the respirator mask 10.

[0056] The controller 30 is further configured to receive the second signal 42 from the second microphone 40. The controller 30 is further configured to determine an ambient sound signal 44 based on the second signal 42. The ambient sound signal 44 is indicative of acoustic energy outside of the clean air envelope 15. In other words, the ambient sound signal 44 may be indicative of acoustic energy in the ambient environment 16.

[0057] The controller 30 is further configured to process the speech signal 38 and the ambient sound signal 44 to generate a processed output signal 54. The processed output signal 54 is configured to cause the speaker 46 to emit acoustic energy. The processed output signal 54 may have improved signal to noise ratio (SNR), improved speech transmission index (STI), lower distortions, etc., as compared to the speech signal 38.

[0058] In some embodiments, processing the speech signal 38 and the ambient sound signal 44 may include at least one of filtering the speech signal 38 and the ambient sound signal 44 and modulating a gain of the speech signal 38 and the ambient sound signal 44. For example, the controller 30 may amplify one or more portions of the speech signal 38 falling within a certain frequency range, filter one or more portions of the speech signal 38 outside of a threshold frequency range, attenuate portions of the speech signal 38 based on the ambient sound signal 44, and other such processing, to generate the processed output signal 54.

[0059] In some embodiments, processing the speech signal 38 and the ambient sound signal 44 may include filtering at least a portion of the ambient sound signal 44 from the speech signal 38. For example, the controller 30 may filter out noise, distortions, etc. from the speech signal 38 (e.g., noise undesirably detected by the first microphone 34) based on the ambient sound signal 44.

[0060] The controller 30 is further configured to deliver the processed output signal 54 to the speaker 46. The speaker 46 may be configured to produce acoustic energy outside of the clean air envelope 15 based on the processed output signal 54. In other words, the speaker 46 may be configured to produce acoustic energy in the ambient environment 16 based on the processed output signal 54.

[0061] The speech enhancement apparatus 20 may improve the intelligibility of the speech of the user wearing the respirator mask 10. Specifically, the processed output signal 54 generated by the controller 30 (by processing the speech signal 38 and the ambient sound signal 44) may be filtered, have a higher signal to noise ratio (SNR) than that of the speech signal 38, a greater or smaller amplitude, and may generally be a cleaner signal than the speech signal 38. The controller 30 may utilize the second microphone 40 to improve the speech signal 38. As a result, the acoustic energy emitted by the speaker 46 due to the processed output signal 54 may provide improved intelligibility of the speech of the user wearing the respirator mask 10. The speech enhancement apparatus 20 may therefore be suitable for use in noisy environments.

[0062] In some embodiments, the speech enhancement apparatus 20 further includes a bone conduction sensor 50 (schematically depicted in FIGS. 1 and 3) configured to sense bone vibrations of the user. The bone conduction sensor 50 may be of any suitable type. The bone conduction sensor 50 may be attached or attachable to the mask body 12, such that the bone conduction sensor 50 contacts the skin of the user wearing the respirator mask 10. It may be noted that the bone conduction sensor 50 may be placed at any position on the head of the user. The bone conduction sensor 50 may be further configured to generate a third signal 52 indicative of the bone vibrations sensed by the bone conduction sensor 50.

[0063] The controller 30 may be operably coupled to the bone conduction sensor 50. The bone conduction sensor 50 may be powered by the power source 32. The controller 30 may be further configured to perform digital sound processing / filtering based on inputs from the first microphone 34, the second microphone 40, and the bone conduction sensor 50.

[0064] Specifically, the controller 30 may be further configured to receive the third signal 52 from the bone conduction sensor 50. The controller 30 may be further configured to determine the speech signal 38 further based on the third signal 52, such that the speech signal 38 is determined based upon the first signal 36 and the third signal 52. In other words, the controller 30 may utilize both the first microphone 34 and the bone conduction sensor 50 to determine the speech signal 38. As a result, the controller 30 may process the first signal 36, the second signal 42, and the third signal 52 to generate the processed output signal 54. This may further improve the quality of the processed output signal 54. Consequently, the acoustic energy emitted by the speaker 46 due to the processed output signal 54 may provide further improved intelligibility of the speech of the user wearing the respirator mask 10.

[0065] Unless otherwise indicated, all numbers expressing feature sizes, amounts, and physical properties used in the specification and claims are to be understood as being modified by the term “about”. Accordingly, unless indicated to the contrary, the numerical parameters set forth in the foregoing specification and attached claims are approximations that can vary depending upon the desired properties sought to be obtained by those skilled in the art utilizing the teachings disclosed herein.

[0066] Although specific embodiments have been illustrated and described herein, it will be appreciated by those of ordinary skill in the art that a variety of alternate and / or equivalent implementations can be substituted for the specific embodiments shown and described without departing from the scope of the present disclosure. This application is intended to cover any adaptations or variations of the specific embodiments discussed herein. Therefore, it is intended that this disclosure be limited only by the claims and the equivalents thereof.

Claims

CLAIMS:What is claimed is:

1. A speech enhancement apparatus configured for attachment to a respirator mask, the speech enhancement apparatus comprising: a first microphone configured to: detect acoustic energy within a clean air envelope of the respirator mask; and generate a first signal indicative of the acoustic energy detected by the first microphone; a second microphone configured to: detect acoustic energy outside of the clean air envelope of the respirator mask; and generate a second signal indicative of the acoustic energy detected by the second microphone; a speaker configured to produce acoustic energy outside of the clean air envelope; and a controller operably coupled to the first microphone, the second microphone, and the speaker, wherein the controller is configured to: receive the first signal from the first microphone; determine a speech signal based at least on the first signal, wherein the speech signal is indicative of a speech of a user wearing the respirator mask; receive the second signal from the second microphone; determine an ambient sound signal based on the second signal, wherein the ambient sound signal is indicative of acoustic energy outside of the clean air envelope; process the speech signal and the ambient sound signal to generate a processed output signal, wherein the processed output signal is configured to cause the speaker to emit acoustic energy; and deliver the processed output signal to the speaker.

2. The speech enhancement apparatus of claim 1, further comprising a bone conduction sensor configured to sense bone vibrations of the user and generate a third signal indicative of the bone vibrations sensed by the bone conduction sensor, and wherein the controller is operably coupled to the bone conduction sensor and further configured to: receive the third signal from the bone conduction sensor; and determine the speech signal further based on the third signal, such that the speech signal is determined based upon the first signal and the third signal.

3. The speech enhancement apparatus of claim 1, wherein processing the speech signal and the ambient sound signal comprises at least one of filtering the speech signal and the ambient sound signal and modulating a gain of the speech signal and the ambient sound signal.

4. The speech enhancement apparatus of claim 1, wherein processing the speech signal and the ambient sound signal comprises filtering at least a portion of the ambient sound signal from the speech signal.

5. The speech enhancement apparatus of claim 1, further comprising a power source operably connected to the controller.

6. The speech enhancement apparatus of claim 5, wherein the power source is rechargeable.

7. The speech enhancement apparatus of claim 1, further comprising a switch operably connected to the controller, wherein the switch is configured to change an operational state of the speech enhancement apparatus.

8. The speech enhancement apparatus of claim 1 , further comprising a housing configured for attachment to a port of the respirator mask, wherein the first microphone and the second microphone are located in the housing.

9. The speech enhancement apparatus of claim 8, wherein the speaker and the controller are located in the housing.

10. The speech enhancement apparatus of claim 8, wherein the housing comprises a fitting configured for selective attachment to the port of the respirator mask.

11. The speech enhancement apparatus of claim 1, wherein at least one of the first microphone and the second microphone is selected from the list consisting of a diaphragm microphone, a MEMS microphone, a pre-polarized microphone, and an electret microphone.

12. A respirator mask comprising : a mask body configured to define a clean air envelope between the mask body and a mouth and a nose of a user wearing the respirator mask; a speech enhancement apparatus comprising: a first microphone configured to: detect acoustic energy within the clean air envelope of the respirator mask; and generate a first signal indicative of the acoustic energy detected by the first microphone; a second microphone configured to:detect acoustic energy outside of the clean air envelope of the respirator mask; and generate a second signal indicative of the acoustic energy detected by the second microphone; a speaker configured to produce acoustic energy outside of the clean air envelope; and a controller operably coupled to the first microphone, the second microphone, and the speaker, wherein the controller is configured to: receive the first signal from the first microphone; determine a speech signal based at least on the first signal, wherein the speech signal is indicative of a speech of the user wearing the respirator mask; receive the second signal from the second microphone; determine an ambient sound signal based on the second signal, wherein the ambient sound signal is indicative of acoustic energy outside of the clean air envelope; process the speech signal and the ambient sound signal to generate a processed output signal, wherein the processed output signal is configured to cause the speaker to emit acoustic energy; and deliver the processed output signal to the speaker.

13. The respirator mask of claim 12, wherein the speech enhancement apparatus further comprises a bone conduction sensor configured to sense bone vibrations of the user and generate a third signal indicative of the bone vibrations sensed by the bone conduction sensor, and wherein the controller is operably coupled to the bone conduction sensor and further configured to: receive the third signal from the bone conduction sensor; and determine the speech signal further based on the third signal, such that the speech signal is determined based upon the first signal and the third signal.

14. The respirator mask of claim 12, wherein processing the speech signal and the ambient sound signal comprises at least one of filtering the speech signal and the ambient sound signal and modulating a gain of the speech signal and the ambient sound signal.

15. The respirator mask of claim 12, wherein processing the speech signal and the ambient sound signal comprises filtering at least a portion of the ambient sound signal from the speech signal.

16. The respirator mask of claim 12, wherein the speech enhancement apparatus further comprises a power source operably connected to the controller.

17. The respirator mask of claim 16, wherein the power source is rechargeable.

18. The respirator mask of claim 12, wherein the speech enhancement apparatus further comprises a switch operably connected to the controller, wherein the switch is configured to change an operational state of the speech enhancement apparatus.

19. The respirator mask of claim 12, further comprising a port located on the mask body, wherein the speech enhancement apparatus further comprises a housing configured for attachment to the port, and wherein the first microphone and the second microphone are located in the housing.

20. The respirator mask of claim 19, wherein the speaker and the controller are located in the housing.

21. The respirator mask of claim 19, wherein the housing comprises a fitting configured for selective attachment to the port of the respirator mask.

22. The respirator mask of claim 12, wherein at least one of the first microphone and the second microphone is selected from the list consisting of a diaphragm microphone, a MEMS microphone, a pre-polarized microphone, and an electret microphone.

Images